Biology paper 1

• What is the definition of active transport?

  The movement of substances from a dilute solution to a more concentrated solution against a concentration gradient, requiring energy from respiration.
• What is aerobic respiration?

  An exothermic reaction in which glucose is broken down using oxygen to produce carbon dioxide and water and release energy for the cells.
• What is anaerobic respiration?

  An exothermic reaction in which glucose is broken down without oxygen to release a small amount of energy, also producing lactic acid.
• What is the function of an antibody?

  Antibodies recognize and bind to specific pathogens.
• What is an antigen?

  Proteins found on the surface of a pathogen that trigger an immune response.
• What are arteries?

  Blood vessels that carry blood away from the heart, usually carrying oxygenated blood and having a pulse.
• What are atria?


  The upper chambers of the heart.
• What are capillaries?

  The smallest blood vessels that run between individual cells and have a wall that is only one cell thick.
• What are carcinogens?


  Substances that significantly increase the risk of developing cancer.
• What is the cell membrane's function?


  Controls the movement of substances into and out of the cell.
• What is the cell wall?

  The rigid structure around plant cells made of cellulose that strengthens the cell.
• What are chloroplasts?


  Organelles that contain chlorophyll, which absorbs light energy from the sun to carry out photosynthesis.
• What are clinical trials?

  Testing of potential new drugs on healthy volunteers.
• What is a communicable disease?

  A disease caused by pathogens that can be passed from one organism to another.
• What is correlation?


  An apparent link or relationship between two factors.
• What is cytoplasm?


  A jelly-like substance where chemical reactions occur and is the site of anaerobic respiration.
• What is diffusion?


  The net movement of particles from an area of higher concentration to an area of lower concentration down a concentration gradient.
• What is a double blind trial?

  A trial where neither the doctor nor the patient knows who is receiving the drug and who is receiving the placebo.
• What is a double circulatory system?

  The circulation of blood from the heart to the lungs is separate from the circulation of blood from the heart to the rest of the body.
• What are limiting factors?

  Conditions that slow down (limit) the rate of a reaction, such as photosynthesis.
• What is metabolism?


  The sum of all the reactions taking place in a cell or the body of an organism.
• What are mitochondria?


  The site of aerobic respiration in cells.
• What is mitosis?


  A type of cell division where one cell divides to form two genetically identical cells.
• What are non-communicable diseases?

  Diseases that are not infectious and cannot be passed from one organism to another.
• What is the nucleus?


  The part of the cell that contains DNA and controls the cell's activities.
• What is an organ?


  A group of different tissues working together to carry out specific functions.
• What is an organ system?


  A group of organs that work together to carry out specific functions and form organisms.
• What is osmosis?


  The diffusion of water through a partially permeable membrane from a dilute solution to a concentrated solution down a concentration gradient.
• What is oxygen debt?


  The extra oxygen that must be taken into the body after exercise has stopped to complete the aerobic respiration of lactic acid.
• What is a partially permeable membrane?

  A membrane that allows only certain substances to pass through.
• What are pathogens?


  Microorganisms that cause disease.
• What is phloem?


  The living vessel in plants that carries dissolved sugars around the plant, with transport occurring in both ways.
• What is photosynthesis?


  The process by which plants make food using carbon dioxide, water, and light.
• What is a placebo?


  A medicine that does not contain the active drug being tested, used in clinical trials of new medicines.
• What are prokaryotic cells?


  Cells that do not have a true nucleus; DNA is free-floating in the cytoplasm, e.g., bacterial cells.
• What is resolution?


  A measure of the ability to distinguish between two separate points that are very close together.
• What are ribosomes?


  The site of protein synthesis in a cell.
• What is a risk factor?

  Something that increases the chances of contracting a disease.
• What are statins?


  Drugs used to lower blood cholesterol levels.
• What are stem cells?

  Undifferentiated cells that have the ability to become any type of cell.