Master GCSE Biology

MS: Muscle tissue (1)

MS:

- Active site is a specific region on the enzyme where the substrate binds (1)

- Substrate is the molecule acted upon by the enzyme (1)

MS:

- The heart has four chambers: two atria/auricles and two ventricles (1)

- Blood enters the right atrium, flows through the right ventricle, and is pumped to the lungs via the pulmonary artery (1)

- Oxygenated blood from the lungs enters the left atrium, flows through the left ventricle, and is pumped to the rest of the body via the aorta (1)

- Valves prevent backflow of blood (1)

MS: Artery (1)

MS:

- Bile is a fluid produced by the liver and stored in the gallbladder (1)

- It emulsifies fats, breaking them down into smaller droplets (1)

- This increases the surface area of fats, making them more accessible to enzymes (1)

MS:

- Red blood cells have a biconcave shape, increasing surface area for gas exchange (1)

- They contain haemoglobin, which binds to oxygen (1)

- They lack a nucleus and organelles, allowing more space for haemoglobin (1)

MS: Transpiration (2)

MS:

- Guard cells surround stomata, openings in the leaf epidermis (1)

- When water is plentiful, guard cells become turgid and open the stomata (1)

- When water is scarce, guard cells lose turgor and close the stomata (1)

MS:

- Arteries carry blood away from the heart at high pressure (1)

- Veins carry blood back to the heart at low pressure (1)

- Capillaries are tiny blood vessels that allow the exchange of nutrients and waste between the blood and tissues (1)

- The walls of capillaries are thin and permeable (1)

MS: Atherosclerosis (2)