Biology

subject overview

We follow the AQA syllabus in Biology. The course is split in three units at both AS and A2 stages.

Learners will take their terminal examination in June. They will study the following units at AS:

•Unit 1: Biology and Disease

•Unit 2: The Variety of Living Organisms

•Unit 3: Practical and Investigative Skills (20% of total AS marks, 10% of total A Level marks)

The learners will study the following units during the A2 units:

•Unit 4: Populations and Environment

•Unit 5: Control in Cells and in Organisms

•Unit 6: Practical and Investigative Skills (10% of the total A Level marks)

unit overview - autumn term

AS Biology year 1 Overview –Biological molecules, cells and transport across membrane
Skills	After carrying out the practical tasks in this topic, students will gain the following skills- Required Practical 1: Investigation into the effect of a named variable on the rate of an enzyme-controlled reaction. AT f Students could use, and interpret the results of, qualitative tests for reducing sugars, non-reducing sugars and starch. AT g Students could use chromatography, with known standard solutions AT f – interpret the results of the emulsion test for lipids Independently follow instructions for the emulsion and biuret test to test samples for lipids. AT f – use and interpret the results of a biuret test for proteins Students could relate the structure of enzymes to their functions Required practical 2- Preparation of stained squashes of cells from plant root tips; set up and use of an optical microscope to identify the stages of mitosis in these squashes and calculation of a mitosis index. AT d – use optical microscopes to observe cells AT e – students prepare, observe and draw squashes of root tip cells e.g. from allium, garlic or hyacinth. Calculate the mitotic index. Analyse data on base frequency and apply knowledge of base pairing, to work out frequency of other bases. Interpret DNA sequence and apply knowledge to work out complementary mRNA code. Required Practical 4 : Investigating the effect of variation in temperature on the permeability of cell membranes using fresh beetroot. Students could plot the data from their investigations in an appropriate format. Required Practical 5: Production of a dilution series of a solute to produce a calibration curve with which to identify the water potential of plant tissue Students could determine the water potential of plant tissues using the intercept of a graph of, e.g. water potential of solution against gain/loss of mass. Students could plot the data from their investigations in an appropriate format. AT b – use a colorimeter to record quantitative measurements AT c – use glassware to produce serial dilutions
Knowledge	Condensation, hydrolysis, monosaccharides, polysaccharides, phospholipids, structure and types of proteins, structure of enzymes, factors affecting enzyme activity, enzyme inhibition. Types of microscope, Magnification and resolution, Cell organelles, eukaryotes and prokaryotes, Cell differentiation, cell division. Phospholipid bilayer structure of cell membrane, diffusion, osmosis, active transport and co transport.
Rationale	Contents in this section introduces students both to structure and to function of biological molecules. Through a study of these topics, students become aware of the tests for different biological molecules like- carbohydrates, proteins and lipids. Students can link how polymerisation of alpha glucose can form starch and glucose. Students will understand the significance of qualitative and quantitative tests. They will appreciate the importance of different types of proteins. This section also gives an idea of the significance of ATP in numerous processes within organisms, as a supplier of energy. Cells are the basic units of life and it's very essential to know the differences between eukaryotic and prokaryotic cells and structure and function of the cell organelles. Understanding of how to prepare a slide and use a microscope will help the students to perform other experiments in biology. This section gives an idea of how uncontrolled cell division can lead to the formation of tumours and of cancers. Many cancer treatments are directed at controlling the rate of cell division. Understanding the double layer structure of cell membrane gives students an idea of hydrophilic and hydrophobic parts. Also, it gives them an idea of changing temperature on the permeability of the cell membrane and how to produce serial dilutions. Students can apply the knowledge of diffusion and active transport in the absorption of products of carbohydrate digestion in the small intestine. This section also introduces facilitated diffusion and active transport.

unit overvew - spring term

AS Biology Overview Mass transport and Immune system

Skills

After carrying out the tasks in this topic, students will gain the following skills:

Required practical 5: Dissection of animal or plant gas exchange system or mass transport system or of organ within such a system.

AT h Students could design and carry out an investigation into the effect of a named variable on human pulse rate or on the heart rate of an invertebrate, such as Daphnia.

Students could be given values of cardiac output (CO) and one other measure, requiring them to change the subject of the equation.

AT b Students could set up and use a potometer to investigate the effect of a named environmental variable on the rate of transpiration.

Students should be able to:

analyse and interpret data relating to pressure and volume changes during the cardiac cycle
analyse and interpret data associated with specific risk factors and the incidence of cardiovascular disease
evaluate conflicting evidence associated with risk factors affecting cardiovascular disease
recognise correlations and causal relationships.

interpret evidence from tracer and ringing experiments and to evaluate the evidence for and against the mass flow hypothesis.

AO1 – Development of knowledge and understanding of antigens and their importance.

AO2 – application of knowledge on the humoral response to explain data on antibody concentrations during the primary and secondary immune responses.

Students should be able to: discuss ethical issues associated with the use of vaccines and monoclonal antibodies Evaluate methodology, evidence and data relating to the use of vaccines and monoclonal antibodies.

Students should be able to:

relate the base sequence of nucleic acids to the amino acid sequence of polypeptides, when provided with suitable data about the genetic code

interpret data from experimental work investigating the role of nucleic acids.

Knowledge

Structure and function of haemoglobins, loading and unloading of oxygen, oxygen dissociation curve, how the properties of the haemoglobin in different organisms relate to their environment, circulatory systems of mammals, stages of cardiac cycle, structure of blood vessels and their function, transpiration and mass flow.

The immune system, Immunity and vaccines, antibodies in medicine, interpreting vaccine and antibody data, HIV and viruses

Genes and triplet code, DNA and chromosomes, the structure of ribonucleic acid, protein synthesis- transcription and translation

Rationale

This section builds on and develops earlier study of heart and blood from GCSE. Students will understand that mass transport systems are just as important for the rapid removal of waste as they are for supplies. Supplies include an immense number of substances, e.g. glucose, oxygen and ions. The greater the metabolic rate of an organism, the greater the demands on its mass transport system. Knowledge about the cardiac cycle, an important topic in the physiology of the cardiovascular system, is required by students of healthcare careers, such as biology, dentistry, medicine, and nursing.

The learning that occurs courtesy of a dissection is vastly different to that afforded by a lecture or textbook lesson. Drawing together many of the topic’s students have heard and read about, dissection gives students first-hand experience in seeing the subject matter. This unique hands-on learning environment can impart an appreciation and understanding of anatomy, unparalleled by second-hand teaching techniques.

Understanding of the diseases and the causes will help to protect from them and lead a healthy life. Infectious diseases are a broad discipline that is almost unique in contemporary medicine with its ability to cure and prevent disease, to identify specific disease causes (microbes), and to deal with diverse, sometimes massive outbreaks. This topic will help researchers to understand more about how the body's immune system responds to a disease, work out how to prevent the disease or improve its treatment, test the effectiveness of potential new vaccines and treatments.

The study of genetic information, variation and relationships between organisms provides scope to perform practical work and to develop practical skills. DNA is pivotal to our growth, reproduction, and health. It contains the instructions necessary for your cells to produce proteins that affect many different processes and functions in your body. Because DNA is so important, damage or mutations can sometimes contribute to the development of disease. Information about DNA helps to understand the study of phylogenetics and evolution.

unit overview - summer term

AS Biology Overview DNA, gene, protein synthesis, genetic diversity and evolution
Skills	After carrying out the tasks in this topic, students will gain the following skills: Students should be able to: relate the base sequence of nucleic acids to the amino acid sequence of polypeptides, when provided with suitable data about the genetic code interpret data from experimental work investigating the role of nucleic acids. Required practical 6: Use of aseptic techniques to investigate the effect of antimicrobial substances on microbial growth. AT d Students could examine meiosis in prepared slides of suitable plant or animal tissue.
Knowledge	Genes and triplet code, DNA and chromosomes, the structure of ribonucleic acid, protein synthesis- transcription and translation Gene mutation, meiosis and genetic variation, genetic diversity and adaptation, types of selection
Rationale	The study of genetic information, variation and relationships between organisms provides scope to perform practical work and to develop practical skills. DNA is pivotal to our growth, reproduction, and health. It contains the instructions necessary for your cells to produce proteins that affect many different processes and functions in your body. Because DNA is so important, damage or mutations can sometimes contribute to the development of disease. Information about DNA helps to understand the study of phylogenetics and evolution. The genetic code is universal, being the same for all the living organisms and therefore provides indirect evidence that organisms have evolved from one another. This knowledge also helps to treat the disorders and enables gene therapy to be used more widely in medicine. Natural selection is one of the central mechanisms of evolutionary change and is the process responsible for the evolution of adaptive features. Without a working knowledge of natural selection, it is impossible to understand how or why living things have come to exhibit their diversity and complexity. An understanding of natural selection also is becoming increasingly relevant in practical contexts, including medicine, agriculture, and resource management. Mutation is the engine of evolution in that it generates the genetic variation on which the evolutionary process depends. To understand the evolutionary process, we must therefore characterise the rates and patterns of mutation. By understanding the concept of mutation, the students will be able to use it in different fields of medicine and agriculture.

knowledge organisers

A knowledge organiser is an important document that lists the important facts that learners should know by the end of a unit of work. It is important that learners can recall these facts easily, so that when they are answering challenging questions in their assessments and GCSE and A-Level exams, they are not wasting precious time in exams focusing on remembering simple facts, but making complex arguments, and calculations.

We encourage all pupils to use them by doing the following:

Quiz themselves at home, using the read, write, cover, check method.
Practise spelling key vocabulary
Further researching people, events and processes most relevant to the unit.