cell biology

• What are the two main types of cells in living organisms?

  Prokaryotic and eukaryotic
• What type of cells are animal and plant cells classified as?

  They are classified as eukaryotic cells.
• What are the main components of prokaryotic bacterial cells?

  They have a cell wall, cell membrane, cytoplasm, and a single circular strand of DNA with plasmids.
• What are organelles?

  • Structures in a cell
  • Have different functions
• How do we express the size difference between objects using orders of magnitude?

  If an object is 10 times bigger, it is said to be 10¹ times bigger.
• What does a prefix in measurement indicate?

  It shows the multiple of the unit.
• What are the prefixes for common metric units and their values?

  • Centi: 0.01
  • Milli: 0.001
  • Micro: 0.000001
  • Nano: 0.000000001
• What is the function of the nucleus in a cell?

  It contains DNA coding for proteins needed to build new cells.
• What is the role of cytoplasm in a cell?

  It is the liquid substance where chemical reactions occur and contains enzymes.
• What is the function of the cell membrane?

  It controls what enters and leaves the cell.
• Where do aerobic respiration reactions occur in a cell?

  In the mitochondria.
• What is the function of ribosomes?

  They are where protein synthesis occurs.
• What is the role of chloroplasts in plant cells?

  They are where photosynthesis takes place.
• What is contained in the permanent vacuole of a plant cell?

  Cell sap.
• What is the function of the cell wall in plant cells?

  It provides strength and a rigid structure to the cell.
• What is cell specialization and differentiation?

  • Cells specialize by undergoing differentiation.
  • This involves gaining new sub-cellular structures suited to their role.
• What is the function of sperm cells?

  They carry the male's DNA to the egg cell for reproduction.
• How do nerve cells transmit signals?

  They transmit electrical signals quickly from one place in the body to another.
• What is the role of muscle cells?

  They contract quickly to move bones or squeeze to cause movement.
• What is the function of root hair cells in plants?

  They take up water and mineral ions from the soil.
• What is the role of xylem cells?

  They transport water and mineral ions up the plant from the roots to the shoots.
• What is the function of phloem cells?

  They carry the products of photosynthesis to all parts of the plant.
• What is the process of differentiation in stem cells?

  • Stem cells undergo differentiation to form specialized cells.
  • Involves switching genes on or off to produce different proteins.
• How do most specialized cells in animals reproduce?

  They can make more of the same cell by undergoing mitosis.
• What is the difference in differentiation ability between animal and plant cells?

  Most animal cells differentiate early and lose this ability, while many plant cells retain the ability to differentiate throughout life.
• What is the purpose of a microscope?

  To enlarge the image of extremely small structures like cells.
• Who first observed cells and in what year?


  Robert Hooke in 1665.
• What are the two lenses in a light microscope called?

  The objective lens and the eyepiece lens.
• What is the maximum magnification of a light microscope?

  Approximately x2000.
• What is resolving power in microscopy?

  It affects resolution, the ability to distinguish between two points.
• What is the formula for calculating magnification in a light microscope?

  Magnification = magnification of the eyepiece lens x magnification of the objective lens.
• What is the purpose of culturing microorganisms?

  To grow many microorganisms in the lab for study.
• What does the culture medium for microorganisms contain?

  Carbohydrates, minerals, proteins, and vitamins.
• What are the two methods to grow microorganisms in the lab?

  1. In nutrient broth solution
  2. On an agar gel plate
• Why must Petri dishes and culture media be sterilized before use?

  To prevent contamination by other microorganisms.
• What is binary fission in bacteria?

  It is the process where one bacterium splits into two.
• How can the number of bacteria in a population be calculated?

  Using the formula: bacteria at beginning x 2^{number of divisions} = bacteria at end.
• What is the purpose of testing antibiotics on bacteria?

  To determine the effectiveness of the antibiotic against bacterial growth.
• What is the zone of inhibition in antibiotic testing?

  It is the clear area around the antibiotic disc where bacteria have died.
• What is the formula for calculating the area of a circle?

  Area = $\pi r^2$, where r is the radius.