bio

• Active transport


  Moves substances from a more dilute solution to a more concentrated solution, against the concentration gradient, requiring energy from respiration
• Diffusion


  Particles move down the concentration gradient, does not require energy from respiration
• Active transport


  Particles are moved against the concentration gradient, requires energy from respiration
• Active transport in animals

  • Cells lining the human small intestine transport sugars like glucose from the lumen (lower concentration) into the cell (higher concentration)
• Cells lining the human small intestine

  • Have many mitochondria to provide the energy for active transport
• Active transport in plants

  • Root hair cells transport ions like magnesium from the soil (lower concentration) into the cell (higher concentration)
• Root hair cells


  • Have many mitochondria to provide the energy for active transport
• Plants need magnesium to make chlorophyll in the leaves
• Mitosis


  The process of cell division that produces two genetically identical daughter cells
• Cell cycle involving mitosis

  • DNA replication
  • Chromosome separation
  • Cytoplasm and cell membrane division
• Body cells contain 23 pairs of chromosomes
• Gametes have unpaired chromosomes
• Chromosomes


  Carry a large number of genes that determine many features
• Animals and plants contain a very large number of cells
• Cells can divide by either mitosis or meiosis
• Cell cycle including mitosis

  1. DNA replication

  2. Chromosome separation

  3. Cytoplasm and cell membrane division
• Functions of mitosis


  • Growth and development of multicellular organisms
  • Repair of organisms
  • Asexual reproduction