Animal Repsonses Flashcards
Research allows for identification of whether a stroke is caused by thombrosis or high blood pressure. The standard emergency treatment of a stroke is to administer a drug that counteracts thombrosis. However if the cause was due to high blood pressure, an alternative treatment,ent would be more effective. Explain why.
The drug could make the problem worse - if the cause of the stroke was found to be a bleed in one of the blood vessels of the brain
Why is nicotine a selective advantage to nicotiana plants
They stop plants being eaten so they are able to survive
Allow increased production of seeds
Than if they were impacted by herbivory
Nicotine has a similar shape to Ach and is able to bind to receptors on the post synaptic membrane. Suggest and explain what effect nicotine could have on the nervous system.
Nicotine is able to bind and open Na ion channels on the post synaptic membrane and cause depolarisation of the membrane. However it remains in the receptor for longer as it can’t be broken down by acetylcholinesterase so the refractory period is longer so a new action potential can’t be regenerated until the products of nicotine have been reabsorbed by the presynaptic membrane
Describe how chemicals are able to be transported to the fruit/ leaves of plants.
Mass flow in the phloem
Xylem by the transpiration stream
Where is the hypothalamus in the brain
Just above the posterior pituitary gland ( as pituitary gland is a distension of the hypothalamus)
Describe how the components of the elbow joint interact to bring about hinge movement.
Triceps and biceps contract in antagonistic pairs
Tendons pull on bones
Ligaments hold bones together
Cartilage reduces friction
Synovial membrane secretes fluid
Synovial fluid is a lubricant
Give 2 reasons why both plant and animals need to be able to respond to changes in their environment .
Both to avoid predation / being eaten
Both to access resources
State 3 differences in the ways in which plant and mammalian hormones operate.
M = endocrine gland P = plant tissues
M= few larger target tissues P = acts on most tissues
M = transported in blood stream P = transported in xylem / phloem
Suggest why it may be hard for a doctor to conclude that symptoms of brain damage are definitely caused by damage to the brain.
May be caused by other underlying conditions
Suggest the long term adverse effects f continued exposure to stress on body function.
Immune system may not respond to infection
Cardiovascular problems
Explain how it is possible for ACh to have an effect on the cells in the skin of the squid.
It is transported in the blood
It bonds to receptors on the cell surface membrane
Activates the G protein and causes the formation of a secondary messenger
Suggest why reduced heart rate is sometimes seen in people who are very aerobically fit.
Increased stroke volume and increased volume of the ventricle chamber
Greater muscle surrounding the heart so blood pumped further with less heart beats
Explain how some sprinters are able to run after taking one breath at the start off the race whilst expending so much energy without the need to carry out aerobic respiration
Cells are able to tolerate an increased level of lactate
There are increased phosphocreatine stores
A is able to be produced very quickly to support muscle contraction
