cells biology b1

• is a plant cell a prokaryotic cell or a eukaryotic cell?

  a eukaryotic cell (a complex cell eg plant or animal whereas a prokaryotic cell is a small simple cell eg bacteria)
• In which sub cellar structures do most of the reactions of aerobic respiration take place?

  mitochondria
• what are the main similarities of a bacterial cell and a plant cell?

  both have a cell membrane, a cell wall and a cytoplasm

  A)
• what are the differences between a bacterial cell and plant cell?

  plant cells have chloroplasts and mitochondria but bacteria do not. Plant cells also have a true nucleus where's bacteria has a singular strand of DNA that floats freely in the cytoplasm. Bacteria also have small rings of DNA called plasmids.
• does the diagram show a plant or animal cell? and how can we tell?

  an animal cell, a plant cell would have a cell wall and a permanent vacuole.

  
• how is the small intestine adapted for its function?

  • villi provide large surface area
  • capillaries are thin - one cell thick for absorption
  • efficient blood supply
  • very long - increasing time for absorption
  • cells have many mitochondria for (aerobic) respiration for active transport or cells have many mitochondria for energy release for active transport
• how is energy for photosynthesis gained by plants?


  LIGHT is captured and absorbed by chloroplasts
• compare the structure of a red blood cell with the structure of a plant cell.

  • red has no nucleus, plant does
  • red has no plant walls
  • red is a biconcave disc - plant can be many shapes
  • red contains hameogoblin
  • red doesn't contain chlorophyll
  • red are much smaller than plant
• explain why the red blood cell bursts but the plant cell do not burst when placed into a beaker of water.

  • water enters the cells by osmosis
  • plant cell has a cell wall which prevents bursting
• give uses of water in plants

  • photosynthesis
  • support
  • for translocation
  • for transpiration
• which cell structure in a leaf mesophyll cell is not found in a root hair cell?

  chloroplasts
• what do root hair cells not contain?

  chloroplasts
• Explain why root hair cells are considered specialised cells.

  they have undergone differentiation and have a special role in the plant
• what is paralysis?


  When nerve cells are damaged, messages can no longer be sent to the muscles properly. This can lead to the loss of the ability to move some or all of your body
• Steps of stem cell treatment

  1. Extract  embryonic stem cells from early embryos.
  2. Grow them in a laboratory
  3. Stimulate them to differentiate into whichever type of specialised cell that we want.
  4. Give them to the patient to  replace their faulty cells.
• Give two drawbacks of using embryonic stems cells in stem cell therapy

  • risk of rejection - seen as foreign substance
  • stem cells have a limited supply
• Two risks of using stem cells in medicine 

  
  

  The stem cells could be infected with a virus whilst in the laboratory, which could then infect the patient.

  • As stem cells divide quickly, there is a chance they could divide uncontrollably once they've been transplanted, and then develop into a tumour.