Cell structures

• nucleus contains genetic material that controls the activities of the cell
• cytoplasm is a gel like substance where chemical reactions happen
• cell membrane controls what enters and leaves the cell
• mitochondria is where aerobic respiration takes place
• ribosomes are involved in protein synthesis
• a cell wall is made of cellulose
• large vacule contains cell sap
• In sexual reproduction, the nucleus of an egg cell fuses with the nucleus of a sperm cell to create a fertilized egg which develops into an embryo
• an egg cell contains:

  1. nutrients in the cytoplasm to feed the embryo
  2. it has a haploid nucleus
  3. after fertilization, its membrane changes shape to stop any more sperm entering
• a sperm cell has:

  1. a long tail so it can swim
  2. packed with mitochondria to provide energy
  3. an acrosome at the front to store enzymes
  4. haploid nucleus
• 1. Epithelial cells line the surfaces of organs
  2. some have cillia on the top surface of the cell
  3. the function of these cells is to move substances