AQA GCSE Biology (Combined Science) Unit 2: Organisation

Flashcards about Organisation , Food Tests , The Digestive System, The Heart and Blood Vessels, Cancer

What is the purpose of the digestive system?

To break down large molecules into smaller, soluble molecules for absorption into the bloodstream.

What are cells?

The basic building blocks of all living things.

What is tissue?

A group of cells with a similar structure and function.

What is an organ?

A combination of tissues carrying out a specific function.

What is an organ system?

Organs working together within a system.

What is the role of amylase?

Enzyme that digests starch into sugars (glucose).

What does a biuret test indicate?

The presence of protein (solution changes from blue to pink-purple).

What is the role of protease enzyme?

Breaks down protein into amino acids.

What is the role of lipase?

Enzyme that digests lipids into glycerol and fatty acids.

What is the function of capillaries?

Narrow vessels that form networks to closely supply cells and organs between veins and arteries, facilitating the transfer of substances.

What are enzymes?

Biological catalysts that speed up chemical reactions without being changed or used up.

What is the function of bile?

An alkaline substance produced in the liver and stored in the gall bladder that neutralises stomach acid and emulsifies fats into small droplets.

What is the pulmonary circulation?

Circulatory system that serves the lungs, bringing deoxygenated blood to exchange carbon dioxide for oxygen at the alveoli.

What is the systemic circulation?

Circulatory system that serves the rest of the body, transporting oxygen and nutrients to cells and carrying carbon dioxide and waste away.

What is the role of the sino-atrial node (SAN)?

Located near the right atrium, it stimulates the atria to contract.

What is the role of the atrio-ventricular node (AVN)?

Located between the ventricles, it stimulates them to contract.

What are some lifestyle factors that increase the risk of coronary heart disease?

High-fat diet, smoking, and prolonged stress.

What are statins?

Drugs used to lower cholesterol levels in the blood.

What are stents?

Mechanical devices used to stretch narrow or blocked arteries, restoring blood flow.

List components of blood.

Red blood cells, white blood cells, platelets, and plasma.

What is the function of red blood cells?

Transport oxygen attached to haemoglobin.

What is the function of white blood cells?

Form part of the immune system and ingest pathogens and produce antibodies.

What is the function of platelets?

Important blood clotting factors.

What is cancer?

The result of uncontrolled cell growth and division, forming a tumour.

What is cardiac output?

A measure of the volume of blood pumped by the heart each minute.

What is the function of xylem?

Transport water and minerals from roots to leaves in a transpiration stream; provide support to the plant structure.

What is the function of phloem?

Transport dissolved sugars (glucose) from photosynthesis throughout the plant.

What is transpiration?

The loss of water from the leaves of the plant by evaporation and diffusion.

What is translocation in plants

The movement of sucrose and amino acids in phloem, from regions of production (source) to regions of storage/use (sink).

How do plants use glucose produced during photosynthesis?

For respiration, to produce cellulose for cell walls, to synthesize amino acids and proteins, and stored as starch.

What is the function of the stomata?

The stomata are small openings on the surface of leaves that allow for gas exchange, including the uptake of carbon dioxide and the release of oxygen and water vapor.

What is the effect of smoking on the cardiovascular system?

Increases blood pressure and damages the lining of arteries, increasing the risk of blood clots and heart disease