Long process questions

• High blood sugar process?

  1. Receptors detect an increase in blood glucose
  2. The pancreas releases insulin which travels down a blood vessel
  3. Liver and muscle cells absorb glucose from the blood
  4. Liver and muscle cells store glucose as glycogen
  5. Blood sugar returns to normal
• Low blood sugar process?

  1. Receptors detect a decrease in blood glucose
  2. Pancreas releases glucagon which travels down a blood vessel
  3. Liver and muscle cells break down glycogen into glucose
  4. Liver and muscle cells release glucose into the blood
  5. Blood sugar returns to normal
• Describe the differences in the processes of osmosis and active

  transport?

  1. Osmosis is the movement of water molecules - Active transport is the movement of molecules
  2. In osmosis, movement is from higher water concentration to lower water concentration - In active transport, movement is from lower concentration to higher concentration.
  3. Osmosis is a passive process - Active transport requires energy
  4. Active transport requires membrane proteins - Osmosis does not
• Describe the stages of protein production in a cell?

  1. A complementary copy of the section of DNA is made
  2. mRNA carries the complementary code from the nucleus to a ribosome
  3. Proteins are formed from amino acids
• Describe the events occurring in a degradation reaction?

  1. Enzyme and substrate fit together
  2. Reaction occurs at the active site of the enzyme
  3. Two products are formed
• Describe the events occurring in an addition reaction?

  1. Enzyme and substrate fit together
  2. Reaction occurs at the active site of the enzyme
  3. One product is formed
• Describe the stages of the process that would be used to produce genetically engineered bacteria, after the required gene has been extracted from the source cell?

  1. Plasmid is extracted from the bacterial cell
  2. Required gene is inserted into the plasmid
  3. Enzymes seal the gene into the plasmid
  4. Modified plasmid is inserted into a bacterial host cell
• Describe the fermentation pathway in muscle cells?

  1. Glucose is broken down into pyruvate
  2. Pyruvate is converted into lactic acid
  3. 2 ATP are produced
• Describe similarities and differences in the process of fermentation in yeast cells and muscle cells?

  Similarities

  1. Glucose in converted into pyruvate
  2. Takes place in the cytoplasm
  3. Is anaerobic
  4. Is enzyme controlled
  5. Produces 2 ATP molecules

  Differences

  1. The end products in yeast cells are ethanol and CO2
  2. The end products in animal cells are lactate
• Describe the sequence of events resulting in the production of two daughter cells.

  1. Chromosomes line up along the equator
  2. Spindle fibres shorten
  3. Pairs of chromatids are pulled apart
  4. Chromosomes move to opposite poles
  5. 2 nuclei form
  6. Cytoplasm divides
• Describe how a stimulus is detected at the skin and how the message is then carried into and across the spinal cord?

  1. Stimulus is detected by receptors
  2. An electrical impulse is sent
  3. Message goes from sensory neuron -> inter neuron -> motor neuron
  4. Message moves across a synapse by neurotransmitters
• Explain why the structure and number of villi make absorption an efficient process in the small intestine?

  1. Villi have good blood supply
  2. Villi have a large surface area
  3. Villi have thin walls
  4. There are lots of villi
  5. They increase the surface area
• Describe the light reactions stage of photosynthesis?

  1. Light energy is trapped by the chlorophyll
  2. Water is split into oxygen and hydrogen
  3. Oxygen diffuses from the cell
  4. ATP and hydrogen are produced
• Describe the carbon fixation stage of photosynthesis?

  1. Controlled by enzymes
  2. ATP provides the energy
  3. Hydrogen is joined with carbon dioxide
  4. Glucose is produced
• Describe how the leaching of nitrates can result in a reduction in the number of freshwater organisms in lochs?

  1. Algal populations increase causing an algal bloom
  2. Algal bloom reduces light levels killing aquatic plants
  3. Bacteria feed on dead plants / algae
  4. Bacteria greatly increase
  5. Bacteria use up large quantities of oxygen
• Describe how new species are formed?

  1. Initial population is split
  2. Different mutations occur in each subpopulation
  3. Some mutations are advantageous
  4. Natural selection occurs because of selection pressures and only the best advantaged survive to reproduce
  5. Subpopulations are no longer able to interbreed to produce fertile offspring.