biology - P1

• • Only prokaryotic cells have plasmids.
• What are examples of eukaryotic cells?

  Plant and animal cells
• What are plasmids?


  Small rings of DNA
• What shape is DNA in prokaryotae?


  DNA is in a single loop in prokaryotae
• which type of cell is bigger and more complex?

  Eukaryotic cells are bigger and more complex
• Why do bacteria have free-floating DNA?

  So that they can reproduce quicker
• What is a flagellum?

  A tail-like structure that helps the cell move faster
• Most animal cells have the following parts:

  A nucleusCytoplasmA cell membraneMitochondriaRibosomes
• As well as the parts found in animal cells, plant cells also have

  ChloroplastsA permanent vacuole filled with cell sapA cell wall
• What is the function of the nucleus?

  The nucleus contains the genetic material (DNA) and controls the cell's activities.
• What is the function of the cell wall?

  The cell wall strengthens the cell
• What is the function of the cytoplasm?

  • The cytoplasm is a jelly-like substance where chemical reactions take place in the cell. It contains enzymes that control these chemical reactions.
• What is the function of the cell membrane?

  The cell membrane controls what goes in and out of the cell.
• What is the function of the mitochondria?

  The mitochondria are where aerobic respiration takes place. They're the powerhouse of the cell.
• What is the function of the ribosomes?

  The ribosomes are where protein is synthesised (made).
• What is the function of chloroplasts?


  Chloroplasts contain the chlorophyll needed for photosynthesis.
• What is the function of the vacuole?

  • The vacuole stores extra water and sap to help keep the cell turgid and give it extra support.
• What is a specialised cell?

  A specialised cell is a cell that has special adaptations that help it carry out its particular function.
• Differentiation

  the process of cells becoming specialised.
• The xylem are found in the plant stem
• • The xylem carry water and dissolved minerals from the roots of the plant to the leaves.
• The xylem have thick walls containing lignin
• How is the xylem adapted to its function?

  The xylem is a long tube, and has no organelles, so water and dissolved minerals can flow easily.
• • The phloem carries dissolved sugars up and down the plant.
• What is diffusion?

  Diffusion is the spreading out of particles, resulting in a net movement from an area of higher concentration to an area of lower concentration.
• What factors affect the rate of diffusion?

  Factors which affect the rate of diffusion are: the difference in concentrations (concentration gradient)the temperaturethe surface area of the membrane
• What is osmosis?

  Osmosis is the diffusion of water from a dilute solution to a concentrated solution through a partially permeable membrane.
• What is active transport?

  Active transport moves substances against a concentration gradient. This requires energy from respiration
• What does amylase do?

  • Amylase breaks down starch into glucose.
• Where is amylase produced?

  Amylase is produced in the salivary glands, pancreas, and small intestine.
• What does protease do?

  Protease breaks proteins down into amino acids.
• Where is protease produced?

  Protease is produced in the stomach, pancreas, and small intestine.
• Where is lipase produced?


  Lipase is produced in the pancreas and the small intestine
• What does lipase do?


  Lipase breaks lipids down into fatty acids and glycerol.
• • Capillaries have thin walls (one cell thick) to allow glucose and oxygen to diffuse through them. They are also used to connect arteries to veins. Capillaries have thin walls (one cell thick) to allow glucose and oxygen to diffuse through them. They are also used to connect arteries to veins.
• What is coronary heart disease?

  n coronary heart disease layers of fatty material build up inside the coronary arteries, narrowing them. This reduces the flow of blood through the coronary arteries, resulting in a lack of oxygen for the heart muscle.
• How are stents used to treat coronary heart disease?

  Stents are used to keep the coronary arteries open.
• What are benign tumours?


  not cancerous
• What are malignant tumours?

  cancerous tumours
• What happens in preclinical trials?

  In preclinical trials, the drug is tested on cells, tissues, and animals.