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• What is the purpose of the cell membrane in a plant cell?


  It determines which substances go in and out of the cell.
• What is the function of the cell wall in a plant cell?


  It provides structural support.
• What is the role of the vacuole in a plant cell?


  It is important for structure.
• Where do most cellular reactions take place in a plant cell?

  In the cytoplasm.
• What is the function of ribosomes in a plant cell?


  They are responsible for protein synthesis.
• What do chloroplasts do in a plant cell?


  They are involved in photosynthesis.
• What is the function of mitochondria in a plant cell?


  They produce energy.
• What is the role of the nucleus in a plant cell?


  It holds the DNA and acts as the control center of the cell.
• What are the main differences between plant and animal cells?

  Plant cells have a cell wall, vacuole, and chloroplasts, which animal cells do not have.
• What is the structure of a bacterial cell?

  It has a cell membrane, cytoplasm, chromosome, ribosomes, and a cell wall.
• What is cell differentiation?


  It is the process where cells become specialized for their specific functions.
• How do specialized cells differ from each other?


  They have different structures and functions based on their roles in the body.
• What are the main types of specialized cells and their functions?

  • Neurons: transmit signals
  • Muscle cells: contract and relax
  • Skin cells: protect the body
  • Villi cells: increase surface area for absorption
• What is the role of stem cells?


  They have the potential to differentiate into any type of cell.
• How can stem cells be used in medicine?


  They can be used to regenerate damaged tissues or organs.
• What is the process of diffusion?


  It is the movement of substances from an area of high concentration to an area of low concentration.
• What is osmosis?


  It is the movement of water through a partially permeable membrane from high water concentration to low water concentration.
• What is active transport?


  It is the movement of substances against a concentration gradient, from low to high concentration.
• What is the hierarchy of biological organization?


  1. Cells
  2. Tissues
  3. Organs
  4. Organ systems
• What is the function of the digestive system?


  It breaks down food and absorbs nutrients.
• What are the main organs of the digestive system and their functions?

  • Mouth: mechanically breaks down food
  • Salivary glands: produce amylase
  • Liver: produces bile
  • Gallbladder: stores bile
  • Small intestine: absorbs nutrients
  • Stomach: digests food
  • Pancreas: produces enzymes
  • Large intestine: removes excess water
• What does lipase do?


  It breaks down fats into fatty acids and glycerol.
• What does protease do?


  It breaks down proteins into amino acids.
• What does amylase do?


  It breaks down starch into sugars.
• How do enzymes work?


  They form an enzyme-substrate complex and then release products while remaining unchanged.
• How does temperature affect enzyme activity?


  Enzyme activity increases with temperature until an optimal point, after which it denatures.
• How does pH affect enzyme activity?


  Extreme pH levels can denature enzymes, affecting their activity.
• What is the pathway of air through the respiratory system?


  Air goes from the mouth/nose to the trachea, bronchi, bronchioles, and alveoli.
• What is the function of alveoli in the respiratory system?


  They are the sites of gas exchange and have a large surface area.
• What is the cardiovascular system's function?


  It pumps blood throughout the body and facilitates gas exchange.
• What is the pathway of blood through the heart?

  Blood enters through the vena cava, goes to the right atrium, right ventricle, lungs, left atrium, left ventricle, and then to the aorta.
• What is the role of valves in the heart?


  They ensure blood flows in one direction.
• What is the difference between arteries and veins?


  Arteries carry oxygenated blood under high pressure, while veins carry deoxygenated blood under low pressure.
• What are the components of blood?

  Blood consists of serum, red blood cells, white blood cells, and platelets.
• What is cardiovascular disease?


  It is a condition where fatty deposits build up in the coronary arteries, leading to blood clots and potential heart attacks.
• What are the risk factors for cardiovascular disease?


  Smoking, high blood pressure, and excessive salt or fat in the diet.
• What happens when too many cells die due to cardiovascular disease?


  It can lead to a heart attack.
• What is the liquid component of blood called?

  Plasma
• What is the main function of red blood cells?


  To carry oxygen
• Do red blood cells have nuclei?


  No, they do not have nuclei