biology p1 - cell biology.

• What are the two types of cells?

  Eukaryotic and prokaryotic
• What distinguishes eukaryotic cells from prokaryotic cells?

  Eukaryotic cells have membrane-bound organelles
• What is the size comparison between prokaryotic and eukaryotic cells?

  Prokaryotic cells are much smaller
• What is the composition of the prokaryotic cell wall?

  Peptidoglycan
• How is genetic information stored in a prokaryotic cell?

  As chromosomal and plasmid DNA
• What are plasmids?

  Small, circular loops of DNA
• What advantages do plasmids provide?

  They carry genes for antibiotic resistance
• What is order of magnitude?

  A power of ten for size comparison
• How many metres are in a centimetre (cm)?

  1 x 10^-2 metres
• How many metres are in a millimetre (mm)?

  1 x 10^-3 metres
• How many metres are in a micrometre (µm)?

  1 x 10^-6 metres
• How many metres are in a nanometre (nm)?

  1 x 10^-9 metres
• What is the difference in order of magnitude between a human hair and the HIV virus?

  3 orders of magnitude
• What are the components of both plant and animal cells?

  • Nucleus
  • Cytoplasm
  • Cell membrane
  • Mitochondria
  • Ribosomes
• What additional components are found in plant cells?

  • Chloroplasts
  • Permanent vacuole
  • Cell wall
• What is the function of the nucleus other than storing genetic information?

  Controls cellular activities
• Describe the structure of the cytoplasm.

  Fluid containing organelles and nutrients
• What is the function of the cytoplasm?

  Site of cellular reactions and transport
• What is the function of the cell membrane?

  Controls entry and exit of materials
• What is the function of the mitochondria?

  Site of aerobic respiration producing ATP
• What is the function of ribosomes?

  Joins amino acids during protein synthesis
• What is the plant cell wall made of?

  Cellulose
• What is the function of the plant cell wall?

  Provides strength and prevents bursting
• What does the permanent vacuole contain?

  Cell sap with salts and sugars
• What is the function of the permanent vacuole?

  Supports the cell and maintains turgidity
• What is the function of chloroplasts?

  Site of photosynthesis
• How are sperm cells adapted to their function?

  • Haploid nucleus for genetic information
  • Tail for movement
  • Mitochondria for energy
  • Acrosome with enzymes for egg digestion
• How are nerve cells adapted to their function?

  • Long axon for impulse transmission
  • Dendrites for receiving impulses
  • Myelin sheath for insulation and speed
• How are muscle cells adapted to their function?

  • Protein filaments for contraction
  • Mitochondria for energy
  • Merged cells for coordinated contraction
• How are root hair cells adapted to their function?

  • Large surface area for absorption
  • Thin walls for easy water uptake
• How are xylem cells adapted to their function?

  • No margins for continuous water flow
  • Thick walls for structural support
• How are phloem cells adapted to their function?

  • Sieve plates for transport of substances
  • Companion cells for energy in transport
• What is cell differentiation?

  Process by which cells become specialized
• Why is cell differentiation important?

  Produces different tissues and organs
• When do most animal cells differentiate?

  Early in their life cycle
• How long do plant cells retain the ability to differentiate?

  Throughout their entire life cycle
• What is the purpose of cell division in mature animals?

  Repair and replacement of cells
• What changes occur in a cell during differentiation?

  Acquisition of structures for specific functions
• Define magnification.

  Number of times bigger an image appears
• Define resolution.

  Ability to distinguish two close objects