biology essay 2022 prediction

How To Answer Biology Essay Questions

Table of Contents:

What Exam Skills are Required to Pass AQA Biology? . We all know that a well designed and rigorous revision schedule is necessary to pass any exam. Here are some tips to revise for Biology.

Before the exam: Try and relax in the last half-an-hour or so before the exam. Read a book, sit quietly somewhere, listen to music – whatever works for you. Just don’t do any last-minute revision. It almost certainly won’t stay in your head anyway. So long as you’ve revised well in the weeks leading up to the exam you should be OK.

Video advice: How to write a good biology essay by Mr. Wanyama

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Tips on Answering AQA Biology Exam Questions – Be clear and concise in your answers. For diagrams, don’t fuss too much over perfect accuracy but make sure that all the key points are there, in the right place, and clearly labelled. For “Brief notes” questions, bullet-point sentences containing relevant information will do as well as, if not better than, a brief essay where the information required is buried under too many words. If you are asked to show your working, do so clearly, making use of the available space to answer the question. Don’t skip too many lines of working at once.

KCSE 2022 Biology Essay Questions and Answers (KCSE 2022 Prediction Questions)

Here are KCSES 2022/2022 Biology Essay Questions and Answers (KCSE 2022 Prediction Questions). Content: 31 pages with 60 questions and answers.

Needed at nighttime stage of photosynthesis it combines using the hydrogen ion in the light stage to create glucose, proteins and lipids low concentrations cuts down on the rate of manufacture of energy and food while high concentrations results in a rise in the quantity of energy and food formed

BIOLOGY (231/2) Revision Questions (Essays): Expected Responses

Has a cell membrane; with pores; that regulates substances entering and leaving the cell; cytoplasm; contain sugars and salts; for maintaining its osmotic pressure; also has a liquid medium; for all biochemical reactions; nucleus; contain chromosomes having hereditary material; and controls all the activities of the cell; ribosomes; are sites for protein synthesis; golgi bodies/apparatus; for secretion of hormones and enzymes; formation of lysosomes; lysosomes; contain lytic enzymes for breaking down worn-out organelles; secretory vesicles; formed from golgi apparatus for secreting substances; smooth endoplasmic reticulum; synthesizes and transports lipids; rough endoplasmic reticulum; transport proteins; nucleolus; controls the activities of the nucleus; produces ribosomes; mitochondria; form sites for energy production; centrioles; formation of cilia and flagella; forms spindle fibres used in cell division; plant sap vacuoles; store salts and other dissolved substances; controls osmotic pressure and turgidity of cells; food vacuoles involved in digestion of engulfed food; chloroplasts; form sites for photosynthesis in plant cells; Max.

Video advice: How to get TOP MARKS in a biology essay: AQA A-level 25 mark essay on paper 3

Learn how to write the 25 mark essay on the AQA A-level paper 3. I fully explain the mark scheme, how to analyse the titles, how to structure your paragraphs and how to write a top plan for success. I model the plan for ‘The Importance of Diffusion’ 2017 title.

AnsweringEssayQuestions

COMMUNICATION IN THE BIOLOGICAL SCIENCES Department of Biology.

Don’t simply create a drawing and expect the teacher to determine that which you were thinking out of this. (Unless of course the issue only insists upon create a drawing. ) Don’t expect the teacher to obtain the relevant information inside a ocean of irrelevant information. Don’t expect the teacher to see between your lines making connections that you ought to make.

The question will always involve two or more related items. “Compare” means that you should explain the similarities between the two items. Ordinarily, instructors do not want you to simply list the similar characteristics, but explain the characteristics and/or how they are similar. “Contrast” means that you should explain the differences between the two items. Typically, a comparison of the similarities and differences between the two items highlights some major concepts in the topic at hand. Be sure to try to address these in your answer. This type of question usually involves the use of specific examples from class.

Biology Form 4 Kssm Questions And Answers – Fill Biology Form 4 Kssm Questions And Answers, Edit online. Sign, fax and printable from PC, iPad, tablet or mobile with pdfFiller ✔ Instantly. Try Now!

Video advice: HOW TO WRITE EXAM ESSAYS! UNIVERSITY BIOLOGY STUDENT TIPS + ADVICE

HOW DO I WRITE MY EXAM ESSAYS? ��⏰

How do you answer an essay question?

6:509:355 Rules for Answering ESSAY Questions on Exams - YouTubeYouTubeStart of suggested clipEnd of suggested clipDon't restate the prompt in your introduction. Instead write an interesting thesis statement thatMoreDon't restate the prompt in your introduction. Instead write an interesting thesis statement that covers the prompt. But in your own words. And finally ensure your conclusion. Synthesizes.

How do you write a short answer question in biology?

2:018:53How to answer short response science questions - YouTubeYouTubeStart of suggested clipEnd of suggested clipThe verb in the first question is described in the verb in the second sentence is explained. TheseMoreThe verb in the first question is described in the verb in the second sentence is explained. These are two different words that require you to do two different things in your answer.

How do you write a biology essay?

You should create a good first impression regarding your comprehension about the topic of your essay in the introduction section.

• State and elaborate on the topic of your paper.
• Outline a brief literature review of the topic.
• Outline the parameters you've used in your paper.
• State your main points and arguments.

How do you write a long answer in biology?

5 Exam tips for Biology

• Structure your answers efficiently. There are some easy traps to fall into when it comes to crafting an answer in your Biology exam. ...
• Draw if it's easier. ...
• Do the multiple-choice questions first. ...
• Figure out the key terms in the question. ...
• Highlight the key terms in your answer.

What is the proper way to answer exam questions?

Strategies for answering exam and test questions

• Read through the options and try to eliminate the ones that aren't right. ...
• Don't struggle over a question. ...
• Answer all the questions. ...
• When you check back through your paper and think an answer is wrong - change the answer.

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Biology KCSE Essay Questions and Answers Paper 2; Over 1,000

KCSE BIOLOGY PAPPER TWO 231/2 -ESSAYS FROM 1995 -2023

  a). Describe how insect pollinated flowers are adapted to pollination ( KCSE1995)

• Progesterone
• Luteinizinghormone
• Describe how excretion takes place in: ( KCSE1995)
• MammalianKidneys
• Greenplants
• a).Explainhowthemammalianskinisadaptedtoperformitsfunctions (20marks; KCSE 1996)

b). Describe how new plants arise by asexual reproduction (20 marks; KCSE 1996)

• a). What is parasitism? (KCSE1997)

b). Describe how the tapeworm is adapted to a parasitic mode of life (KCSE 1997)

• a). What is meant by the term digestion? (KCSE1997 )

b). Describe how the mammalian small intestine is adapted to its function (KCSE 1997)

• Discuss the various evidences, which show that evolution has taken place (20 marks; KCSE 1998)
• Explain how the mammalian intestines are adapted to perform their function (20 marks; KCSE 1998)
• a). Describethe:
• Process of inhalation in mammals ( KCSE 1999)
• Mechanisms of opening and closing of stomata in plants (KCSE1999)

b). Explain how the various activities of man have caused pollution of air (20 marks; KCSE 1999)

• a). Describe the role of hormones in the human menstrual cycle (20 marks; KCSE2000)

b). How are leaves of mesophytes suited to their functions (20 marks; KCSE 2000)

• a). State the functions of the following parts of the mammalian ear; (KCSE2001)
• Tympanicmembrane
• Eustachiantube
• Earossicles

b). Describe how semicircular canals perform their functions (KCSE 2001 )

• a). Describe the process of fertilization in a flowering plant ( KCSE2001)

b). State the change that take place in a flower after fertilization ( KCSE 2001)

• a). Describe the role of hormones in the growth and development of plants (20 marks; KCSE 2002)
• a). Name three types of skeletons found in multicellular animals ( KCSE2002)

b). Describe how the cervical, lumbar and sacral vertebrae are suited to their functions

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(KCSE 2002)

• a). Describe the functions of the various parts of the human eye (20 marks; KCSE2003)

                                                                                                                                         1 | P a ge

(b). Describe how fruits and seeds are suited to their modes of dispersal (20 marks; KCSE 2003)

• a). How is the mammalian skin adapted to its functions? (20 marks; KCSE2004)

b). Explain how a biotic factors affect plants (20 marks; KCSE 2004)

• a). Describe how gaseous exchange takes place in terrestrial plants (20 marks; KCSE2005)

b). How is the human eye adapted to its function? (20 marks; KCSE 2005)

• a). Describe how human kidney functions (20 marks; KCSE2006)

b).Describehowwatermovesfromthesoiltotheleavesinatree (20marks; KCSE2006)

• a). Describe the structure and functions of the various parts of the human ear (20 marks; KCSE 2007 )

b). Describe causes and methods of controlling water pollution (20 marks; KCSE 2007 )

• Describe the nitrogen cycle (20 marks; KCSE2008)
• a). State four characteristics of gaseous exchangesurfaces

b). Describe the mechanism of gaseous exchange in a mammal (16 marks; KCSE 2008)

• a). How are flowers adapted to wind and insect pollination? (20 marks; KCSE2009 )

b). Describe the role of the liver in homeostasis in the human body (20 marks; KCSE2009)

• a). Describe the process of fertilization in flowering plants (20 marks; KCSE2010)

b). Describe how a finned fish such as tilapia moves in water (20 marks; KCSE 2010)

• a). Describe the exoskeleton and its function in insects (13 marks; KCSE2011)

b). Describe how accommodation in the human eye is brought about when focusing on a near object (7 marks; KCSE 2011)

• Using a relevant example in each case, describe simple and conditional reflex action (20 marks; KCSE2012)
• a).Usingarelevantexample,describehowanallergicreactionoccursinahumanbeing

(10 marks; KCSE 2012)

b).Describehowenvironmentalfactorsincreasetherateoftranspirationinterrestrialplants

• a). Describe the process of blood clotting in human beings (10 marks; KCSE2013 )

b).Howarerespiratorysurfacesinmammalsadaptedtotheirfunctions? (10marks; KCSE 2013)

• Describe the role of the following organs in excretion andhomeostasis
• The liver (10 marks; KCSE2013)
• The skin during hot environmental conditions (10 marks; KCSE2013 )
• a). Explain how each of the following factors affect the rate ofphotosynthesis:
• Temperature (2 marks; KCSE2014)
• Chlorophyll concentration (2 marks; KCSE2014 )

b). Describe the process of carbohydrate digestion in human beings (16 marks; KCSE2014)

• a). How does excretion take place in plants (4 marks; KCSE2014)

b). Describe the role of the human skin in homeostasis (16 marks; KCSE 2014)

• a).Explainthevariouswaysinwhichseedsandfruitsareadaptedtodispersal (20marks; KCSE 2015)

b). How is a mammalian heart structurally adapted to its function? (20 marks; KCSE2015)

                                                                                                                                         2 | P a ge

• (a).Usingarelevantexampleineachcase,describesimpleandconditionalreflexaction

(20 marks; KCSE 2016)

b). Describe how the mammalian heart is structurally adapted to its function (20 marks; KCSE 2016)

• a ) Explain the importance of protecting the forest ecosystem with reference to the following (20 marks; KCSE 2017 )
• a) Climate change
• b) Biodiversity

c)Biotechnology

d)Water conservation

• e) Pollution
• b) Describe how a mammalian eye is structurally adapted to its functions (20 marks)
• a) Describe the mode reproduction in a named fungus (5 marks)
• b) Describe the roles of hormones in the menstrual cycle (15 marks; KCSE 2018 )
• a) Giving examples, describe the following among organisms (20marks; KCSE 2019 )
• Predator-prey relationship
• b) Explain the effect of increased physical activity on the following organ system (20 marks)
• a)(i)Explain the role of the liver in blood regulation (3 marks ; KCSE 2020)
• Describe how a mammalian heart is adapted to its functions (17 marks)
• b) (i) Explain how the presence of chloroplast in guard cell affect the opening of the stomata (5marks)

(ii) Describe how various environmental factors affect the rate of photosynthesis (15marks)

• a) (i) Explain the role of placenta during pregnancy(10 marks) ( KCSE 2021)
• ii) Explain features and mechanisms that hinder self pollination and self fertilization(10 marks)

b)( i) Describe how xylem is structurally adapted to its functions  (5marks)

(ii) Describe the functions of mammalian blood in the human body(15 marks)

• a i) Describe how plants eliminate waste products(8 marks; KCSE2022 )

ii)Describe the structure and function of mammalian nephron (12marks)

• b) i. Describe five tropic responses and their survival values (15marks)

ii)Describe how mammalian heartbeat is controlled                (5mks)

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A LEVEL BIOLOGY PREDICTED PAPER 2 SUMMER 2022

Subject: Biology

Age range: 16+

Resource type: Assessment and revision

Last updated

6 July 2023

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Predicted paper 2 for summer 2022 exams for (AQA) A Level Biology based on the advance information.

There are a plethora of self-made challenging application/data analysis questions with relevant maths and statistical analysis.

Advance Information: 3.6.4 Homeostasis is the maintenance of a stable internal environment • 3.5.2 Respiration (including Required Practical 9) • 3.6.2 Nervous coordination • 3.5.3 Energy and ecosystems • 3.5.4 Nutrient cycles • 3.7.1 Inheritance • 3.8.2 Gene expression is controlled by a number of features • 3.5.1 Photosynthesis

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A-Level Biology Predicted Papers

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*These downloads are intended for individual use only. If you are a teacher, school or tutor, please purchase a school licence before you use these with your students.*

To buy the licence, click here .

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I've tried to read your mind and think of any problems you might have; I've tried to answer them all here https://primrosekitten.org/faqs/

Customer Reviews

They were very good! many of the predictions were so accurate and it helped me so much in the actual exam and i highly recommend it!!

Topics were on point. The actual paper was just so hard and feel like no one could’ve possibly predicted what the paper was. But yeah topics primrose kitten predicted were 100% spot on

Amazing resource , really helped the student i tutor to check her knowledge and for us to tweak what needed tweaking. Thanks PK!!

Definitely recommend. It tests every bit of knowledge. Would prefer that the walkthrough videos are accessible bc I have to pay extra to be able to view them.

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A-Level Biology revision plan

The predictions were highly accurate (especially for paper 1s!) and I managed to achieve grade 9s using these papers the day before my exams!

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My daughter used the predicted papers for this yr’s GCSEs and found them to be very good. They were quite accurate - chemistry and biology paper 1 were reasonably accurate, whereas physics paper 1, chemistry and physics paper 2 were very accurate and some questions were identical in the exam. Definitely worth the money and would use them again.

Insane predictions. Completely worth it!

Biology Predictions 2024 for Leaving Cert Higher Level

Updated March 2024. Our Biology predictions based on analysis of past papers appear to have coincided and agreed quite closely with one of the mock exams. They were temporarily hidden – and now they are back.

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Biology Notes  (€)

Predictions 2024

While it is impossible to be certain about what is coming up, here are areas to pay special attention to for 2024:

Section A (Short Questions):

Food (featured in Section A for the past 15 years)

Ecology (featured 12 times in the past 15 years, did not feature last year)

Cell Division (not featured as short question since 2021, featured 7 times in the 10 years prior)

Genetics & Evolution

Excretion – Kidneys (not featured as a short question since 2018)

Human Reproduction (not featured in short questions since 2021)

Plant Transport & Osmosis (not featured as a short question since 2017)

Section B (Experiments):

A recent trend has been to ask short questions on the Scientific Method in the first parts of an experiment question so it is a good idea to know this well. (Questions 8, 9 & 10 experiment questions come from the same units of the course each year,  appearing periodically based on the amount of time lapsed since they last appeared)

• Conduct a qualitative test for: Starch, Fat, Reducing Sugar, Protein
• Isolate DNA from plant tissue
• Prepare one enzyme immobilisation and examine its application
• Investigate the effect of light intensity or carbon dioxide on the rate of  photosynthesis
• Investigate the effect of ph/temperature on the rate of one of the following:  amylase, pepsin or catalase activity

Question 10

• Investigate the effect of oxygen, water and temperature on germination
• Investigate the effect of exercise on the breathing rate or pulse rate of a human

Section C (Long Questions):

• Genetic crosses/DNA and RNA/genetics and evolution
• Respiration
• Photosynthesis

Section C (Long Questions with option i.e. Q16 and Q17):

Bacteria, Fungi & Yeast (featured as a long question 13 times in the past 15 years)

Digestive System (not featured as long question for past 2 years)

The Skin/Body Temperature (not featured for the past two years)

Excretion – Kidneys (not featured frequently as option in recent years, not featured last  year)

The Nervous System (featured as an option 10 times in the past 15 years)

Immune System (not featured for the past 2 years)

LC Biology paper layout

Section A: Short Questions  

Answer any five out of seven questions 

Section B: Experiments  

Answer any two of three questions 

Section C: Long Questions  

Answer any four of seven questions. 

An additional part will be added to the last two questions, Q16 and Q17, in which case  candidates answer any two of four parts. 

General patterns of LC Biology questions

Short questions consist of 2 questions from Unit 1, 2 from Unit 2 and 2 from Unit 3. Unit 1: The scientific method, the characteristics of life, food, ecology. Unit 2: Chapters on the cell, enzymes, photosynthesis and respiration, diffusion and osmosis and genetics. Unit 3: The kingdoms of life, chapters on plants and on the human body.

Very common topics for short questions are food, ecology and cell division.

For experimental questions, it is becoming more common to see questions with a variety of different experiments in one question. For example, in 2016 Q7 candidates were asked about a test for a reducing sugar, how to carry out an examination of plant and animal cells and about the immobilisation of an enzyme.

The scientific method is almost always asked about in experimental questions.

Other common experiments include experiments about enzymes (immobilisation, denaturation, effect of temperature and pH on enzyme activity), about plants (digestive activity during germination, conditions necessary for germination) and about using a microscope to examine plant/animal cells.

For long questions, there is almost always a question on genetics (DNA and RNA, genetic crosses, evolution, genetic engineering), ecology, respiration/ photosynthesis/ enzymes and plants (plant responses, structure of flowering plants, exchange in flowering plants, sexual reproduction in flowering plants.

For Q14 and 15, there will almost always be a part (a, b or c) where you have to write about various topics. For example, in 2016 Q15 (c) candidates were asked about the skeleton, a dietary deficiency of a water-soluble vitamin, a genetically sex-linked disease, vaccination, etc.

Human reproduction often features as a part of Q14 or 15.

2023: what we predicted

• Sexual reproduction
• Cell division
• Diffusion and osmosis

A recent trend has been to ask short questions on the Scientific Method in the first parts of an experiment question so it is a good idea to know this well.

• Visit to an ecosystem – carry6ing out a quantitative study (quadrats), abiotic factors
• Food tests – test for starch, fat, reducing sugars, and protein
• Prepare an enzyme immobilisation and examine its application
• Investigate the effect of water, oxygen, and temperature on germination
• Dissect, display and identify an ox’s or sheep’s heart
• Endocrine system
• Human reproduction
• Plant structure
• Immune system
• The skin/body temperature
• Bacterial, fungi and yeast
• Nervous system

2022: what we predicted

• DNA & RNA
• Plant structure and transport
• Blood/circulatory system
• Use a light microscope to examine animal/plant cells
• Visit to an ecosystem – carrying out a quantitative study (quadrats), abiotic factors
• Investigate the effect of temperature on enzyme activity
• Investigate the influence of light intensity or carbon dioxide on the rate of photosynthesis
• Investigate the effect of I.A.A. growth regulator on plant tissue
• Investigate the effect of water, oxygen and temperature on germination
• Genetic crosses
• Variation and evolution
• Human reproductive system
• Musculoskeletal system
• Plant responses
• Plant reproduction

2021: what we predicted

• Scientific Method
• Cell Division
• Prepare and show the production of alcohol by yeast
• Investigate the influence of light intensity or carbon dioxide concentration on the rate of photosynthesis
• Prepare and examine microscopically a transverse section of a dicotyledonous stem
• DNA & RNA/Genetics
• Blood/human circulatory system
• Human nutrition
• Cell diversity

2020: what we predicted

Short Questions: 

• Human Nutrition
• Plant Reproduction

Experiments: 

• How to use a microscope
• Dissection of the heart
• Ecology – quantitative study
• Enzymes – temperature/ pH/ heat denaturation/ immobilisation
• Digestive activity during seed germination
• *Note that The Scientific Method almost always form part of an experiment question*

Long Questions: 

• Photosynthesis/ Respiration
• Genetic Crosses/ DNA and RNA

Long Questions with options (Q14 and Q15)

• Human Defence System
• Human Reproduction
• Plant Responses
• Transport, storage and gas exchange in flowering plants

2019: what we predicted

For your reference, this is what came up in 2019:

• Cell Structure
• Blood vessels/ Human Breathing
• Food tests/ Prepare and examine animal cells/ Isolate DNA from plant tissue/ Investigate the effect of IAA on plant tissue/ Investigate osmosis
• Prepare and examine a transverse section of a dicot stem

Long Questions

• DNA and RNA/ Protein synthesis/ Genetic crosses
• Enzymes/ Photosynthesis

Long Questions with options (Q14 and Q5)

• Nervous system/ Endocrine system
• Immune system/ Plant responses/ Bacteria/ Heart
• Digestive system

This is what we had predicted:

Short Questions

Food Ecology Respiration Cell division The skeleton and muscles Protista

Experiments

Denaturation/ immobilisation of enzymes Show the production of alcohol by yeast Pulse rate/ breathing rate Dissection of the heart Effect of IAA on plant tissue

Ecology DNA and RNA/ Genetic crosses Sexual reproduction of flowering plants Photosynthesis/ respiration Long Questions with options (Q14 and Q5)

Fungi Plant responses Human nutrition/ food Diffusion and osmosis Human reproduction The nervous system

Not bad, eh?

• Post author: Martina
• Post published: January 22, 2024
• Post category: Biology / Predictions

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Four bioscience predictions for 2022

Cloud computing will dramatically accelerate the rate of biological discovery, writes Markus Gershater

Investing in technology has been critical for firms of every industry in order to weather the turbulence of the last two years. This is especially true in the life sciences, where we've seen rapid adoption of different technologies that have the potential to solve some of the industry's most pressing challenges.

It isn't only about new apps, artificial intelligence, or cloud computing, though. The very experiments and methods that take a drug from idea to patient-ready are being transformed as we speak. The work that began in response to Covid has the potential to make dramatic changes in how we do science and how we bring the products of that science to the world.

There are four areas already seeing substantial shifts, and where we may yet see even further transformation.

Prediction 1: DOE will gain more widespread adoption in biology

The year 2022 will see more widespread adoption of design of experiments (DOE) methodologies. Enabled by this, biologists are going to take on and overcome bigger, more ambitious challenges than ever before. ‘One factor at a time’ experimentation can’t keep pace with the complexity of modern biology, which is why systematic multifactorial experimentation will come to the fore.

The problems that biology must solve are now more complex than ever. ‘Traditional’ methodologies no longer cut it and, against the backdrop of the last two years, this has created a louder conversation about how to use computing in biology. With greater adoption of things like AI/ML, the horizon of tools and methodologies that we’re ready to consider has dramatically widened. We are also starting to think of biology as something that can be done with systematic, parallelised experimentation, rather than a reliance on doing things ‘one at a time’. On top of all of this, a cohort of early adopters are seeing amazing results that many others are keen to emulate.

There’s a renewed sense of urgency and we’ve seen a corresponding explosion of interest in the topic. This should be no surprise: DOE has the potential to exponentially improve research timelines, make research processes much more efficient and it gives rise to insights that weren’t possible before. That’s why this year promises to be an exciting time for R&D, and those that lead the charge with DOE are going to do things we could only have dreamed about in the past.

Prediction 2: Bioprocessing development picks up the pace

Developments in bioprocessing hardware have uncorked many of the bottlenecks we used to experience. But with greater capacity and higher throughput comes far more data at the development stage. Making effective use of that data will be make-or-break for teams in this space and those that tackle it head on will be the most likely to succeed.

In bioprocessing development, investment into high-throughput hardware has led to the ability to carry out a great many experimental runs in parallel. With greater throughput comes greater amounts of data, so much so that it can sometimes take weeks to bring all the data together for even a single experiment. Moving to more sophisticated cloud technologies will allow that data to be parsed, structured and amalgamated into coherent, multifaceted datasets in significantly less time. Being able to quickly combine all of this bioprocessing data under a common format will be really important in enabling development teams to take full advantage of the sophisticated automation technologies they have all invested in.

Those development teams that can properly embrace cloud computing will be able to make full use of available automation tools and therefore see faster, more efficient results. Those that don’t are going to find it much more difficult, and may well fall behind.

Prediction 3: New CDMOs lead the way to cloud-enabled, automated labs

The response to Covid highlighted the importance of our global biomanufacturing capacity.   This, combined with the explosion of therapeutic modalities in recent years has opened up massive opportunities for contract development and manufacturing organisations (CDMOs), both in overall demand, and in specific niches.   New CDMOs are looking to technology as a differentiating factor, employing automation and cloud technologies as never before.

It's well recognised that we need a large amount of flexible manufacturing capacity to respond to this pandemic, and to whatever nature throws at us next.   And this need is likely to increase over time, as biotechnology continues to step up to the world's biggest problems.   A multitude of established pharma and dynamically growing, diverse biotechs are looking to CDMOs to provide or augment their manufacturing capabilities. This has prompted a huge flurry of announcements of capacity increases by existing CDMOs, and the formation of many new CDMOs that are looking to establish themselves in specific niches.It’s these new CDMOs, unencumbered by legacy technologies, who are seizing the opportunity to build out their operations radically differently, with cloud technology and automation transforming how they can run projects and connect those projects with their clients.

Prediction 4: A dramatic increase in the rate of biological discovery

Scientists will increasingly employ dramatically more effective experimental designs. Combined with modern cloud and automation technologies, this will result in a dramatic increase in the rate of biological discovery.

Experiments have always been expensive, and the logistics for assembling all the necessary reagents, cell lines and consumables slow.   Perhaps it’s the still greater timelines and expense imposed by Covid-related supply chain issues that is driving scientists to look at how they could get more bang for their experimental buck.   Whatever the reason, we’re observing a dramatic increase in interest in being able to perform hugely powerful, multifactorial experiments.   This is hugely exciting for a number of reasons.   Firstly, these experiments are able to cut through biological complexity and give transformative insight, unparalleled by more common experimental approaches. But perhaps more importantly for the future, it marks a shift to a way of working where building models of the systems we’re working with is the norm. It points the way towards a future of much more systematic experimental methodologies, supported by automation and   machine learning, that will drive a transformative step-change in the already rapid rate of bioscience progress.  

Transformation happens where powerful technologies and experiments meet

The pandemic has thrown the importance of scientific and technological resources into sharp relief. The impact that humanity has brought to bear upon this crisis is a testament to our success so far, and that impact will continue to leave a legacy; a major part of which being the shift to vastly more powerful methodologies and technologies. Perhaps the greatest legacy of all is one of human ingenuity solving problems against the odds, and the foundations laid for a future industry that stands a far greater chance of stopping the next pandemic in its tracks.

Markus Gershater is chief scientific officer at Synthace 

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Biology Paper 3 Questions and Answers - KCSE 2022 Prediction

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INSTRUCTIONS TO CANDIDATES

• Answer all the questions in the spaces provided.
• You are required to spend the first 15 minutes of the 1 3 / 4  hours allowed for this paper reading the whole paper carefully before commencing your work.
• Candidates should answer the questions in English.

• Place the test tubes in a water bath maintained at 37°C and allow to stand for 30 minutes. Place a drop of the contents from each test tube on a white tile. To each add a drop of iodine solution. Record your observation in the table above. (3 marks)
• Add equal amounts of the Benedict’s solution to test tubes labeled 2and 3; heat to boil. Record your observation.
• Why was the test tube labeled 1 included in the experiment? (1 marks)
• Account for the results in tubes 1, 2 and 3. (3 mark)
• Suggest the identity of solution L. (1 mark)
• Why were the test tubes placed in water bath maintained at 37°C (1mk)

• Similarities- (2 marks)
• Difference- (1 mark)
• Habitat: (1 mark)
• Reasons: (3 marks)
• Simple or compound leaf
• Leaf venation
• Leaf margin
• Leaf colour
• Explain how specimen T is adapted to its mode of pollination (3 marks)
• Using floral parts only of specimen T, state the class to which it belongs. (1mark)
• Give a reason for your answer in (c) (i) above. (1mark)

CONFIDENTIAL

• About 3ml of solution L- enzyme diastase per student About 3ml of 0.05% NaCl solution with a dropper
• About 3ml of 1.4% NaCl solution with a dropper About 10ml of starchsolution per student
• 3 test tubes
• Measuring cylinder (5 ml or 10 ml) White tile
• Iodine solution with a dropper Benedict’s solution with a dropper Test tube holder
• Warm water bath maintained between 35-38°C Thermometer
• Means of labeling for the three test tubes 1 dropper
• Test tube rack Hibiscus leaf labelled P
• Tradescantia leaf labelled R
• Bougainvillea twig with a flower labelled T Maize/ Grass leaf labelled X
• Bidens pilosa leaf labelled Y

Marking Scheme

• Test tube 2 - Changes to green/yellow (1 mark) Test Tube 3 - Colour changes to orange/brown (1 mark)
• Control experiment (1 mark)
• Starch was not broken down/converted into reducing sugar in test tube/due to lack of sodium chloride and solution L (enzyme); more reducing sugar in test tube 3 than test tube 2; due to higher concentration of sodium chloride; sodium chloride accelerates hydrolysis of starch. (4 marks)
• enzyme/diastase (1 mark)
• Provide optimum temperature/best temperature for enzyme activity. (1 mark)

• Body is divided into 3 parts; head, thorax and abdomen
• Have one pair of antennae;
• Have 3 pairs of legs
• M has 2 pairs of wings, N has one pair of wings;
• M has a brown colour, N has black and yellow stripes;
• M has smooth body, N has hairy body;
• Dorsal –Ventrally flattened body enabling it to fit into cracks and crevices
• Legs are ventrally placed for fast movement and are easily folded under the body enabling entry into cracks and crevices
• Smooth forewing to reduce resistance while gliding through cracks and crevices
• Brown/dark brown body colour for camouflage.
• 1(a) Leaf simple.......................................................... go to 2 1(b) Leaf compound.................................................... Y 2(a) Leaf has network venation................................... go to 3 2(b) Leaf has parallel venation ................................... go to 4 3(a) Leaf margin smooth/ entire .................................. T 3(b) Leaf margin serrated. ...........................................  P 4(a) Leaf purple............................................................. R 4(b) Leaf green............................................................. X   Rj 1(i)1(ii), i(a) i(b), Rj two for 2 in steps, ....go to.Must be there (8 marks)
• Brightly coloured bracts/conspicuous bracts; to attract insect pollinators; Tubular corolla;to be reached by visiting insects/ anther and stigma enclosed inside the tube; landing platform for insects pollinators; (3 marks)
• Dicotyledonae; Rj wrong spellings (1 mark)
• Floral parts are in fives; Rj multiples of fives acc. Correct no. of named floral part.(1 mark)

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• v.23(7); 2022 Jul

Inductive prediction in biology

Valentí rull.

1 Botanic Institute of Barcelona, Barcelona Spain

Associated Data

Reliable predictions of long‐term ecological and evolutionary processes require more information than the periodicity of the astronomical forces that drive them.

In an earlier essay (Rull,  2022a ), I discussed the possibility of making inductive predictions in biology and that this approach is hampered by the lack of fundamental biological laws that can be described mathematically, as is usual in physics. The development of such laws, in turn, is thwarted by the nature of life and its evolution both of which are characterized by emergent properties such as complexity, contingency and unpredictability. Biological induction – and thereby knowledge – is largely based on generalization after hypothesis testing, an approach that has also been called accommodation. I also argued that there is no reason to underrate accommodating procedures with respect to inductive prediction, a usual practice in theoretical biology.

However, even in the absence of fundamental laws, it might be possible to develop a logical, usually mathematical, description for biological processes that could serve as a basis for physics‐like inductive predictions. In this essay, I discuss this potential for predicting some evolutionary and long‐term ecological processes. The emphasis is on periodic long‐term processes, as these have the highest predictive potential owing to their potentially quantifiable recurrence. It is important to differentiate this approach from evidence‐based predictive modelling, where the model is the hypotheses and is progressively refined/reframed to accommodate empirical observations. In contrast, inductive prediction relies on immutable underlying laws and uses these to predict empirical observations that would prove the validity of such rules; for instance by finding evidence for predicted evolutionary processes in the fossil record (Rull,  2022a ).

The fossil record already provides us with evidence for biotic responses to repeated environmental events on a diurnal to million‐year scales. Four main bands of recurrent environmental variability have so far been defined: calendar (< 1 year), solar (1–10 4  years), Milankovitch (10 4 –10 6  years) and galactic (> 10 6  years) (Rodríguez‐Tovar,  2014 ). This paper focuses on the galactic and Milankovitch bands and the long‐term ecological and evolutionary responses. Within these time domains, the best‐known recurrent phenomena are the Phanerozoic extinction events during the past ∼540 million years (or Myr) – the causes of which are still under debate – and the Pleistocene global biotic reorganizations linked to glacial–interglacial cycles during the past 2.6 Myr.

…even in the absence of fundamental laws, it might be possible to develop a logical, usually mathematical, description for biological processes that could serve as a basis for physics‐like inductive predictions.

Phanerozoic cycles of extinction

The hypothesis by the American palaeontologists Raup & Sepkoski ( 1984 ) that Phanerozoic extinctions occur periodically and that they are linked to external events has been intensively debated. They identified 12 extinction pulses during the past 250 Myr with an average periodicity of 26 Myr and suggested that this periodic behaviour could be linked to solar or galactic cycles. The authors based their hypothesis on Fourier analysis of a time series of fossil records encompassing ∼3,500 families of marine animals – vertebrates, invertebrates and protozoans – compiled by one of the authors (Sepkoski) and the Harland and Odin geological timescales, which were the best developed at the time. The differences between the observed extinction peaks and those predicted by the 26‐Myr harmonic function ranged between 0 and 6 Ma for the Harland scale and 0.6 and 10.6 Myr for the Odin scale. The debate started when other scientists criticized Raup and Spekoski's analysis on the basis of taxonomic, chronological and statistical deficiencies. Both repeated their analysis over the following 4 years and confirmed the 26‐Myr periodicity, although they admitted that more data were needed to resolve the controversy.

Further attempts using improved databases and updated timescales extended to the last 500 Myr gave similar periodicities ranging from 27 to 30 Myr (Melott & Bambach,  2014 ). This paper used an updated time‐series database (Fig  1 ) and a new paleobiology database (PBDB) and identified two types of periodicities in the recurrence of extinction: ∼27 Ma and ∼62 Myr (both with errors of ± 3 Myr), acting together in and out of phase during the past 470 Myr. Although the authors did not favour any particular cause – neither for the extinction events nor for their periodicity – others did associate periodic extinctions with astronomical causes, such as the passage of the Solar System through the galactic plane, which has a ∼63‐Myr periodicity (Gillman & Erenler,  2017 ). However, these conclusions were not universally accepted. For example, Erlykin et al  ( 2017 ) used an updated time‐series database and Fourier analysis and concluded that no statistically significant periodicities exist in the extinction record for the past ∼500 Myr. These authors dismissed astronomical causes of extinction events and favoured other mechanisms, such as asteroid impacts, climatic changes and plate tectonic processes.

The average duration of the extinction cycles – the interval between consecutive peaks – is ~ 27 Myr. Cam, Cambrian; Ord, Ordovician; Sil, Silurian; Dev, Devonian; Car, Carboniferous; Per, Permian; Tri, Triassic; Jur, Jurassic; Cre, Cretaceous; Ter, Tertiary. Based on Melott & Bambach ( 2014 ) and literature therein.

There is a tendency of linking long‐term periodic patterns to astronomical causes given the latter's periodic nature, but reliable evidence of this relationship remains elusive. Other proposed causes for extinctions, such as meteorite impacts, global biogeochemical shifts, volcanism, reversals in Earth's magnetic field or the formation of large igneous provinces (LIPs) caused by massive magma outbreaks, are more difficult to associate with periodic phenomena. However, some of these causes may also have a periodic component. For example, the formation of LIPs owing to the release of mantle plumes (flood basalts) into the oceans causes major biogeochemical disruptions by releasing large amounts of sulphates and carbon dioxide with significant environmental and biotic consequences at a global level. Using cross‐wavelet and other time‐series analyses, Prokoph et al  ( 2013 ) found a periodicity of 62–65 Myr for this phenomenon during the past ∼500 Myr, which is consistent with the pattern of extinctions among marine organisms.

There is a tendency of linking long‐term periodic patterns to astronomical causes given the latter's periodic nature, but reliable evidence of this relationship remains elusive.

If we assume that extinction events are periodic, it should be possible to make two types of inductive predictions: the timing of the next extinction event and the timing of a hypothetical past event still unnoticed in the fossil record. For example, using the periodicity of 63 Myr for Solar System dynamics, Gillman & Erenler ( 2017 ) anticipated that the next extinction event should occur in 1–2 Myr. Curiously, this coincides with current extrapolations of extinction rates, although the causal mechanisms are radically different, being based on anthropogenic extinctions (Rull,  2022b ). Regarding non‐astronomical causes, Prokoph et al  ( 2013 ) used the periodicity of mantle plume releases (62–65 Myr) to predict a still unidentified extinction event 440–450 Myr ago.

Conversely, if periodicity is a methodological artifact and extinctions occur randomly (Erlykin et al ,  2017 ), the potential for developing mathematical laws from the fossil record and inductive predictions would be significantly less. In that case, the best option would be falling back on accommodating approaches, that is, hypothesis testing including evidence‐based predictive modelling to make further generalization whenever possible. Some attempts have been made in this regard by modelling the biosphere as an ecosystem; these models seem to be able to reproduce extinction events from only internal functioning without the need for external forces (Likhoshvai & Khlebodarova,  2021 ).

Pleistocene glacial–interglacial cycles

On another scale, it is clear that Earth has undergone glacial–interglacial cycles, at least during the Pleistocene, with drastic changes in average temperature. This is based on the analysis of the oxygen isotopic composition (δ 18 O) of planktonic foraminifer shells; as these are sensitive to temperature, it allows to reconstruct paleotemperature records from deep‐sea marine cores. In the 1970s, some palaeoceanographers noted that Pleistocene δ 18 O curves matched the so‐called Milankovitch cycles, which had been defined in the 1920s by the Serbian astronomer Milutin Milanković, who estimated long‐term variations in solar energy reaching the Earth depending on orbital parameters such as eccentricity (100‐kyr period), obliquity (41‐kyr period) and precession (23‐kyr period). It thus seemed logical to attribute the Pleistocene glacial–interglacial changes to these astronomical cycles (Imbrie & Imbrie,  1979 ).

Altogether, more than 100 climatic oscillations occurred during the Pleistocene, of which ∼40 reached the magnitude of glacial–interglacial cycles. These cycles show a clear periodicity of 41 kyr (obliquity) until 800 kyr before present and then change to a periodicity of 100 kyr (eccentricity) (Fig  2 ; Raymo,  1994 ). Although the Milankovitch cycles do match the pace of Pleistocene glacial cycles, the changes in the incoming solar energy seem to be insufficient to trigger glacial–interglacial cycles. The intensity of climatic changes is therefore explained by amplifying, nonlinear mechanisms, such as changes in albedo, thermohaline circulation or the concentration of atmospheric greenhouse gases (Ellis & Palmer,  2016 ).

Lower eccentricity values (rounder orbit) imply lower solar radiation and are correlated with glaciations (white bands), whereas higher eccentricity values (more elliptical orbit) correspond to higher insolation values and are correlated with interglacial phases (grey bands). Redrawn and modified from Ellis & Palmer ( 2016 ).

Such a framework would mean a high predictive potential. For example, we could predict that the next glaciation will begin within a few thousand years given that the last glaciation occurred between about 110 and 20 kyr with a 100‐kyr periodicity. We can make a similar prediction – about 1,500 years from now – if we compare the Holocene, the interglacial period in which we live, with former interglacial phases of about the same duration (Tzedakis et al ,  2012 ). However, the abovementioned amplifying mechanisms complicate things, especially as these are affected by human activities. The most important of these factors is the anthropogenic increase in carbon dioxide, which creates a greenhouse effect that could delay the next glaciation period by 40 kyr or more. Some predictions go even further and suggest that a global temperature increase of 2°C would be enough to provoke a cascade effect that triggers a long‐lasting state of ‘hothouse’ Earth without further glaciations (Steffen et al , 2018 ).

Glacial–interglacial cycles and the associated sea‐level shifts have affected the biosphere and ecological systems from the deep sea to the highest mountains. By way of example, the recurrent expansion (glacial) and contraction (interglacial) of polar ice masses, along with the repeated contraction and expansion of climatic zones and their corresponding biomes, have drastically influenced the terrestrial biota and its evolution (Fig  3 ). During glaciations, many species were restricted to residual areas, known as refugia, from which they expanded again during interglacials. Even in tropical zones, changes in precipitation patterns created refugia for many species that were driven by the glacial expansion of deserts. Moreover, significant glacial sea‐level changes of 100 m or more created new migration pathways or biogeographical barriers for terrestrial and marine organisms (Rull,  2020 ). The situation reversed during interglacials when geographical patterns were similar to those observed today.

Most of the continent was covered by tundra and dry steppes, whereas the mixed and deciduous forests typical of today's central Europe were restricted to refugia of the southern peninsulas (Iberia, Italy, Greece). The Mediterranean biomes that today dominate these peninsulas were absent and restricted to northern Africa. Redrawn and modified from Rull ( 2020 ).

… the response of forests with long‐lived trees to environmental changes can take centuries, which significantly inhibits any predictions of how the biota reacts to climate change.

However, translating the predictive potential of periodic climatic changes into biotic patterns is not straightforward owing to the large variability of how the biota responds to environmental changes. These responses are determined by idiosyncratic traits, such as life‐cycle duration, response lag, tolerance, phenotypic plasticity or the ability to migrate over longer distances. For example, foraminifers are single‐celled organisms with a short life cycle and their population immediately responds to temperature variations. This is why these organisms are excellent proxies for palaeotemperature reconstructions that provided empirical support to the orbital theory of Pleistocene climatic change. In contrast, the response of forests with long‐lived trees to environmental changes can take centuries, which significantly inhibits any predictions of how the biota reacts to climate change. Generally, organisms with a wider tolerance to temperature changes and/or high phenotypic plasticity are more able to acclimate and thereby survive, whereas stenothermic organisms are more sensitive. When climatic shifts overcome the acclimation capacity of organisms, species can still undergo adaptive evolution or migrate before going extinct. Yet, migration also differs among species owing to diverse propagation methods, migration velocities and changing spatial patterns, including the emplacement of refugia. All these factors affect the composition of ecosystems, to the effect that recurrent glacial–interglacial contractions and expansions have been accompanied with significant, but also stochastic and largely unpredictable modifications at the community level. The Pleistocene has also been an epoch of intense evolutionary change, notably at the species level, which further complicates the establishment of straightforward relationships between climate and the biota (Rull,  2020 ).

Thus, even in the case of periodic behaviour of Pleistocene climate cycles, the biological responses have not been homogeneous and straightforward, and a high degree of contingency and unpredictability remains. As a consequence, the glacial–interglacial shrinking–expansion cycles would be somewhat predictable at a biome level, but the taxonomic composition of biomes, their geographical distribution and the dynamic of their communities are largely unpredictable, even within a periodic palaeoclimatic framework. Practically, this means that it would be hard to make reliable predictions about either the reaction of the biota to future climate changes or about the timing and extent of past extinction events in response to climate change. The best solution is again the use of accommodating procedures, including the use of non‐inductive evidence‐based modelling of climate–biota relationships.

Physical reductionism

At the temporal scales analysed here, periodicity, and hence predictability, is strongly associated with astronomical cycles that influence the biosphere. This could be considered a manifestation of physical reductionism, as biological periodicity, if it exists, would be caused by astronomical factors, which obey fundamental physical laws.

To consider this possibility, it is important to take into account the statistical errors in the definition of periodic cycles and the accuracy of the astronomical–biological correlations. For example, in the case of Phanerozoic extinctions, errors of a few Myr are common for defining extinction cycles (Melott & Bambach,  2014 ). Even if these errors could be considered small in comparison with the duration of an extinction cycle, they are of a magnitude that largely surpasses the ecological timescale and are therefore difficult to explain in terms of biological responses to astronomically triggered environmental changes. The same occurs with chronological correlations between astronomical and extinction cycles. At this scale, methodological constraints in the definition of periodicity are still significant hurdles for making a conclusive assessment.

… life once more comes out as ‘noise’ that does not adhere to fundamental physical laws.

At the Milankovitch scale, however, the statistical errors are significantly smaller and fall within the magnitude of ecological–environmental interactions. But even if biological cycles agree with astronomical periodicities, at least in the case of simple organisms with rapid responses to climate changes, it does not seem to work for more complex and longer lived organisms: the astronomical periodicity is largely distorted by the idiosyncratic responses of different taxa to climatic shifts. This suggests that the possibility of using physics‐like laws could be a matter of scale which progressively decreases when the time band approaches ecological timescales.

Predictive power

In summary, it can be inferred that inductive prediction power is at a maximum for long‐term biological processes that can be linked to periodic astronomical causes, although the errors associated with the statistical fitting between physical events and biological responses must be taken into account. Inductive prediction power decreases however with the increasing complexity of biological responses that significantly distort astronomical periodicity. This is equivalent to saying that inductive prediction power is directly proportional to the possibility of reducing biological processes to fundamental physical forces. Therefore, life once more comes out as ‘noise’ that does not adhere to fundamental physical laws. This noise is characteristic of long‐term ecological and evolutionary processes, which are inherent to life and require accommodating inductive approaches – hypothesis testing and further generalization – rather than inductive predictions based on fundamental laws. Thus, even in the case of biological processes triggered by well‐known physical causes, the characteristic biological contingency and unpredictability hamper the use of purely reductionist approaches. In addition, humankind – which is also a consequence of evolution on Earth – is a further distortion factor, as it can significantly disrupt future extinction and ecological patterns thus magnifying unpredictability.

Disclosure statement and competing interests

The author declares that he has no conflict of interest.

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