Cell structure

• Living things are called organisms and carry out the 7 life processes: movement, respiration, sensitivity, growth, reproduction, excretion and nutrition
• All living things are made of cells
• Unicellular organisms are made of only one cell e.g. bacteria
• Multicellular organisms are made of many cells e.g. humans
• Animal and plant cells contain a nucleus, cell membrane, ribosomes, mitochondria and cytoplasm
• Only plant cells contain a cell wall, vacuole and chloroplasts
• The nucleus controls the cell's activities because it contains DNA
• The cell membrane controls what enters and leaves the cell
• The cytoplasm is a jelly-like substance where reactions happen
• The cell wall surrounds plant cells and provides strength and support
• The chloroplasts are where photosynthesis take place and contain chlorophyll to absorb sunlight
• The vacuole contains liquid that stores substances for the cell and keep it rigid
• Mitochondria release energy for the cell during respiration
• Ribosomes are the site of protein synthesis

Cell specialisation

• Specialised cells have a structure which is suited to their function
• Muscle cells, red blood cells, sperm cells, egg cells, xylem cells, phloem cells and root hair cells are all examples of specialised cells
• Unicellular organisms have some special adaptations which allow them to survive, such as pseudopodia (false feet) to help them to catch food and move, flagella (like tails) which help movement, and vacuoles to remove waste from their bodies.

Using Microscopes

• A microscope is used to make something small appear much larger
• A microscope is made of many parts, each with specific functions (eye piece lens, stage, objective lenses, handle, light/mirror, course focusing knob, fine focusing knob)
• Magnification is calculated with the following equation: Magnifying power = eyepiece lens magnification x objective lens magnification
• A light microscope can be used to study a sample of living tissue

Principles of Organisation

• A group of the same cells working together is called a tissue
• A group of tissues working together for the same function is called an organ
• A group of organs working together for the same function is called an organ system
• There are many organ systems in the human body including: respiratory, excretory, nervous, muscular, circulatory, skeletal and digestive
• Multicellular organisms require organ systems to carry out life processes

Disciplinary knowledge

• Know the difference between a scientific question and a non-scientific question (a question that science can answer)
• Define and understand the term hypothesis.
• Describe a practical procedure for a specified purpose.
• Recognise and use expressions in decimal form
• Understand and use the symbols: =, <>, >, ∝ , ~
• Recognise the importance of scientific quantities and understand how they are determined.
• Include a coherent and sensible order of steps, with sufficient detail to obtain valid results, including suggested equipment.
• Use SI units (e.g., kg, g, mg; km, m, mm; kJ, J) and IUPAC chemical nomenclature unless inappropriate.

Practical skills

• Read a scale accurately
• Produce clear, labelled scientific drawings
• Obtain a clear image using a light microscope

Sexual and Asexual Reproduction 

• Cells reproduce by sexual or asexual reproduction 
• Sexual reproduction is when sex cells (gametes) from two individuals fuse to form a new organism 
• Organisms produced during sexual reproduction are genetically different to each other and their parents 
• Asexual reproduction is when an organism makes a copy of itself to form a new individual 
• Organisms produced during asexual reproduction are genetically identical to each other and the parent cell 
• A gamete is a reproductive cell.  
• In animals, gametes are sperm and egg cells. In plants, gametes are pollen and egg cells 
• Fertilisation is the fusion of the nucleus from a male gamete with the nucleus of a female gamete 
• Multicellular organisms, including animals and plants, carry out sexual reproduction 
• Unicellular organisms such as bacteria and fungi carry out asexual reproduction 

 Puberty and the Reproductive System 

• Puberty occurs as a series of physical changes that cause a child to develop and become capable of reproduction 
• The physical changes seen in females include rapid growth, the onset of periods, breast development, hair growth and hip widening. 
• The physical changes seen in males include rapid growth, sperm production, hair growth, vocal changes and shoulder broadening
• During adolescence, there are physical and emotional changes that are controlled by sex hormones 
• A hormone is a chemical messenger that travels around the body in blood 
• Males and females produce the sex hormones, testosterone and oestrogen, in different quantities  
• The female reproductive system includes the vagina, cervix, uterus, fallopian tubes and ovaries. Each organ has a specific function 
• The male reproductive system includes the penis, urethra, sperm duct, glands, scrotum and testis. Each organ has a specific function 

The Menstrual Cycle 

• The female reproductive cycle is called the menstrual cycle and lasts (on average) 28 days.  
• Menstruation occurs when the lining of the uterus is shed, and lasts (on average) between 1-5 days  
• Ovulation is the release of a mature egg from an ovary, and occurs on day 14 of the menstrual cycle 

Animal Reproduction 

• Fertilisation occurs in the fallopian tube 
• Pregnancy occurs when a fertilised egg successfully embeds into the lining of the uterus 
• Sex hormones control the menstrual cycle 
• A zygote is a fertilised egg cell. A zygote rapidly develops into an embryo, which develops into a foetus 
• Gestation is when the foetus grows in the uterus until it is ready to be born 
• The placenta and umbilical cord allow for the transfer of nutrients between a mother’s blood and the blood of a developing embryo 
• The foetus develops in an amniotic sac filled with amniotic fluid for protection 

Plant Reproduction 

• The parts of a flower include the stamen (anther and filament), petal, sepal, and carpel (stigma, style and ovary)  
• Pollination is the transfer of pollen from the anther of one plant to the stigma of another plant 
• Pollination is carried out by insects, animals or wind. Flowers are specialised to attract insects 
• Pollen grains are specialised for transfer by wind or by insects. This specialisation can be seen using a microscope 
• Pollen lands on the stigma and travels down the style to reach the ovary 
• Fertilisation occurs when the pollen fuses with an egg found inside an ovule in the ovary 
• After fertilisation, the ovule develops into a seed and the ovary develops into a fruit. The seed contains the embryo which will grow into a new plant 
• Germination is the development of a seed into a plant 
• Germination requires water, oxygen and warmth 
• Seed dispersal is needed so that the new plant grows far away from the parent plant so that they don’t compete for water and light 
• Seeds are dispersed by animals externally (stuck to fur), animals internally (being eaten), wind, water or by an explosion 

Disciplinary knowledge: 

• Construct and interpret frequency tables and results tables 
• Consider the best way to present data 
• Produce clear, labelled scientific drawings

Ecosystems 

• An ecosystem is the interaction of a community of organisms with the non-living parts of their habitat 
• A population is a group of the same organism, living in the same area 
• A community is made of several different populations living in the same area that depend on each other for survival 

Sampling 

• A sample if a smaller part of something that gives an idea of the whole 
• Sampling techniques are used to measure the size of a population in a habitat. These can be random or systematic
• Random sampling is used to estimate the total population of an organism in an area/the distribution of species in an area 
• Systematic sampling is used to determine the effect of a specific factor on the distribution of an organism 
• Transects and quadrats are used to count the number of individuals in a specific location and area 
• A transect is a straight line from a specific point, along which quadrats are placed at regular intervals 
• A quadrat is a square frame that can be used to count non-moving or slow-moving organisms 

Food Chains and Webs 

• Feeding relationships within a community can be represented by food chains and webs 

• The arrows in a food chain or food web represent the direction of energy transfer 
• Producers are organisms that can make their own food using energy from the Sun or chemicals 
• Plants are producers that can make their own food (glucose) using sunlight in the process of photosynthesis 
• Consumers are organisms that cannot make their own food, so must eat other organisms 
• Primary consumers eat producers, secondary consumers eat primary consumers and tertiary consumers eat secondary consumers 
• Predators are consumers that eat other animals, called prey 
• Bioaccumulation is the gradual build-up of a harmful toxin in an organism through a food chain 
• A toxin is a harmful chemical 
• In a stable community the numbers or predators and prey increase and decrease in cycles 
• If there is a change in one population then this affects other populations in the community 
• The trophic level of an organism shows how many steps it is from the start of the food chain 
• Trophic levels can be represented by numbers, starting at level 1 with plants and algae. Further trophic levels are numbered subsequently according to how far the organism is along the food chain. 
• Level 1: Plants and algae make their own food and are called producers 
• Level 2: Herbivores eat plants/algae and are called primary consumers 
• Level 3: Carnivores that eat herbivores are called secondary consumers 
• Level 4: Carnivores that eat other carnivores are called tertiary consumers. Apex predators are carnivores with no predators 
• Biomass is the mass of a living or recently dead tissue 
• Pyramids of biomass represent the mass of all organisms in each trophic level of a food chain 
• Pyramids of number represent the number of organisms in each trophic level of a food chain 
• Producers are always found at the bottom of a pyramid of numbers or pyramid of biomass 

Competition for Resources 

• Biotic factors are living things that can affect a community 
• Examples of biotic factors include predators, the availability of food and disease 
• Abiotic factors are non-living things that can affect a community 
• Examples of abiotic factors include temperature, light, wind and water availability 
• Competition occurs when organisms compete for limited resources 
• Animals often compete with each other for space, mates and food 
• Plants often compete with each other for space, water, minerals and light 

Disciplinary knowledge 

• Describe representative sampling techniques 
• Apply representative sampling techniques to different scenario and explain why it is appropriate
•  Interpret a line (scatter) graph 
• Plot two variables from experimental or other data 
• Draw a line of best fit 
• Construct and interpret bar charts, pie charts and histograms 
• Find the arithmetic mean and range of a set of data 
• Draw conclusions from given observations. 
• Draw conclusions from a graph
• Draw conclusions from a table 

Practical skills 

• Apply a representative sampling technique and explain why it is appropriate

The Musculoskeletal System
The functions of the human skeletal system include support, protection, movement and making blood cells

• The skeleton and muscles interact to allow movement
• The function of muscles is to allow movement by contracting and relaxing
• Antagonistic muscles work in pairs to coordinate movement
• Examples of antagonistic muscles include biceps and triceps

The Breathing System
The breathing system is an example of an organ system and consists of specialised tissues and organs

• The breathing system allows air to move into and out of the lungs through the nose and mouth
• The breathing system consists of the nose, mouth, trachea and lungs (to include the bronchi, bronchioles and alveoli)
• The trachea is a rigid tube that connects the mouth and nose to the lungs
• The bronchi are two rigid tubes that allow air to pass into and out of each lung. These divide further into bronchioles
• The alveoli are microscopic air sacs that are the site of gas exchange
• Breathing is a mechanical process which results in volume and pressure changes inside the lungs
• Breathing includes inhalation and exhalation, and is coordinated by the action of the diaphragm, ribcage and intercostal muscles
• The bell jar model can be used to represent the changes in volume and pressure that take place during breathing
• The alveoli are adapted for efficient gas exchange because they are numerous, have one cell thick walls, are spherical (large SA:Vol ratio), have a good blood supply and are moist
• Gas exchange occurs between the alveolar air and the bloodstream. Oxygen diffuses into the blood and carbon dioxide diffuses into the alveolar air
• Respiration is a chemical reaction that releases energy in cells
• Oxygen diffuses from air in alveoli into the blood to be transported around the body for respiration
• Carbon dioxide is a waste product from respiration and is transported from respiring cells, into blood which diffuses into alveoli to be breathed out
• The composition of air changes during breathing
• Inhaled air has more oxygen and less carbon dioxide than exhaled air
• Exercise, asthma and smoking all have an effect on breathing

Drugs
A drug is any substance that has an effect on the body

• Medicinal drugs are used to treat people suffering from pain or disease
• Medicinal drugs are used to treat asthma
• Recreational drugs are taken for enjoyment. Some are legal and some are illegal. There is debate surrounding which drugs should be illegal
• Stimulants are drugs that increase alertness and activity levels
• Depressants are drugs that slow down reactions
• Hallucinogens are drugs that alter a person’s perception (awareness of their surroundings)
• Some drugs are addictive, making it difficult to stop taking them
• Overuse of drugs can affect behaviour and cause damage to organ systems

Disciplinary knowledge

• Any anomalous values should be examined to try to identify the cause and, if a product of a poor measurement, ignored.
• Visualise and represent 2D and 3D forms including 2 dimensional representations of 3D objects
• Describe representative sampling techniques
• Apply representative sampling techniques and explain why it is appropriate

Practical skills

• Measure and observe the effects of forces including the extension of springs