Biology Organisation

• What is the 'lock and key' hypothesis?

  The shape of the enzyme active site and substrate are complementary, so can bind together to form an enzyme substrate complex
• What is the role of enzymes in the digestive system?

  Enzymes in the digestive system break down food into nutrients, which the body uses for energy, growth, and cell repair.
• What is the role of the large intestine in the digestive system?

  Absorption of water and electrolytes, formation and storage of feces.
• What is the role of the liver in the digestive system?

  The liver's role in the digestive system is to produce bile for fat digestion and to detoxify substances from the blood.
• What is the role of the small intestine in the digestive system?

  Absorption of nutrients.
• What is the role of the stomach in the digestive system?

  The stomach is responsible for breaking down food through the secretion of digestive enzymes and acids, as well as mixing and storing food before it is further digested in the small intestine.
• What is the role of the pancreas and the salivary gland in the digestive system?

  Pancreas: Produces digestive enzymes and hormones such as insulin. Salivary Gland: Produces saliva to moisten food and begin the digestion of carbohydrates.
• What is the main function of the digestive system?

  The main function of the digestive system is to break down food into nutrients that can be absorbed by the body and eliminate waste.
• Where is bile made and where is it stored?

  Its made by the liver and is stored in the gallbladder.
• What is metabolism?

  The sum of all the reactions in the cell or organism.
• How does pH affect enzyme function?

  Any change in this pH significantly affects the enzyme activity and/or the rate of reaction.
• Where are carbohydrase, proteases and lipase produced in the body?

  Carbohydrases: Salivary glands, pancreas, small intestine Proteases: Stomach, pancreas, small intestine Lipase: Pancreas, small intestine
• What is the role of the carbohydrase in the digestive system?

  Carbohydrase breaks down carbohydrates into simple sugars for absorption.
• What is the role of the protease in the digestive system?

  Protease breaks down proteins into amino acids in the digestive system.
• What is the role of lipase in the digestive system?

  To break down fats.
• How are products of digestion used?

  They are used to build bigger molecules such as carbohydrates and proteins. Glucose is used as a substrate in respiration.
• What is the heart?

  An organ that pumps blood around the body.
• What is the purpose of the circulatory system?

  The purpose of the circulatory system is to transport oxygen, nutrients, hormones, and waste products throughout the body.
• How does the double circulatory system work?

  One pathway carries blood from the heart to the tissues.

  One pathway carries blood from the heart to the lungs.
• Where does pumped blood from the right ventricle go?

  The lungs
• Where does the blood from the left ventricle go?

  Body tissues
• Why are the walls of the left ventricle thicker?

  The left ventricle has to pump blood at a higher pressure around the whole body.
• What is the purpose of valves in the heart?

  To stop backflow of blood.
• What is the purpose of the coronary arteries?

  Coronary arteries supply the heart muscle with oxygenated blood.
• Describe the process of blood flow through the heart.

  1. Blood enters the right atrium via vena cava and the left atrium via the pulmonary vein.

  2. Atria contract, pushing blood into ventricles, closing valves.

  3. Ventricles contract; blood from the right goes to the lungs via pulmonary artery, left to the body via aorta.
• What are the 3 types of blood vessel in the body?

  Arteries, veins, capillaries
• How are capillaries adapted for their function?

  Function: enable transfer of substances between the blood and tissues.

  Walls are one cell thick-short diffusion path

  Permeable walls-substances can diffuse across.

  Narrow lumen-blood moves slowly-more time for diffusion.
• What's a cell?

  Basic unit of life.
• What is a tissue?

  A group of cells that perform a specific function.
• What is an organ?

  A group of tissues that work together to perform a specific function in the body.
• What is an organ system?

  An organ system is a group of organs that work together to perform a specific function in the body.
• How is epidermal tissue adapted for its function?

  Protection
• How is palisade mesophyll tissue adapted to its function?

  Contains lots of chloroplasts which allows photosynthesis to progress at a rapid rate
• How is spongy mesophyll tissue adapted for its function?

  Large air spaces between cells for gas exchange.
• How is xylem adapted for its function?

  Transportation
• What is the second unit for AQA GCSE biology?

  Organization
• What are groups of cells called?

  A tissue
• What are cells defined as?

  Basic building blocks of all living organisms
• What is a tissue?

  A group of cells with similar structure and function
• What is an organ?

  A group of tissues performing specific functions