Coordination
What does the optic nerve do?
carries impulses from the receptors to the brain.
What is a postive tropism?
growth towards the stimulus
Where is adrenaline produced?
adrenal glands
Where is ADH produced?
hypothalamus / pituitary
What is moved in the xylem?
Water and minerals by the transpiration stream
What does the suspensory ligament do?
Changes the shape of the lens.
Holds the lens in place
What are auxins?
Plant hormones that control at the tips of roots and shoots
What are the effects of adrenaline?
Increases heart rate, blood flow to muscle and blood sugar level.
Describe two ways in which nervous communication differs from hormonal communication
1. fast(er) (versus slow(er));
2. electrical/impulse (versus chemical); 3. neurones (versus blood);
4. short(er) lasting (versus long(er) lasting);
5. target cells (versus all around body)
How does water get into a plant through its root hair cells?
Osmosis
High conc in soil than in plant.
what is the ciliary muscle?
contracts and relaxes to change the shape of the lens
What is the benefit of positive geotropism in root?
Water and mineral levels higher, deeper in the ground
Explain what is meant by the term hormone (2)
released from gland / endocrine;
travels in blood;
to target (cells/organs) / eq;
effect / response / coordination / controls / causes change / eq;
Describe the effects of ADH in the body
1. collecting duct;
2. more permeable / eq;
3. (more) water (re)absorbed (into blood) /
blood more dilute / eq;
4. osmosis;
5. urine concentrated / less water in urine / less urine;
How is the root hair cell adapted?
It has millions of microscopic hairs so the plant has a bigger surface area for absorbing water.
How does the iris change in bright room?
pupil constricts, radial muscle relax and circular muscle contract.
Where is auxin produced?
the tips of shoot and roots.
What is the function of insulin and glucagon
lowers blood glucose levels and raises blood glucose levels.
What does your body do when its hot?
Hairs lie flat.
Lot of sweat is produced- when it evaporates it transfers energy from the skin to the surroundings cooling you down.
Vasodilation- blood vessels near the surface of the skin widen this means that more blood flows near the surface of the skin meaning that it transfers energy into the surroundings.
How is the transpiration rate affected by increased humidity?
Drier the air, the faster the transpiration.
Because diffusion happens fastest if there is a really high conc in one place and low conc in another.
A characteristic shown by animals is the ability to respond to their surroundings. For example, a person may withdraw their hand from a hot object.
Describe the sequence of events that cause this response.
receptor / nerve ending;
sensory neurone / sensory nerve; impulse / message / signal;
CNS / spinal cord / grey matter; synapse;
relay neurone / relay nerve; motor neurone ;
muscle / effector;
contract;
Plant roots also respond to external stimuli.
Describe the response of roots to gravity and explain how this response benefits the plant.
down / positively geotropic / toward gravity / eq;
anchor / hold plant / stability / eq; (obtain) water / mineral ions / nutrients / eq;
How can you test for diabetes?
Urine test to see if there is glucose in urine. If so they are diabetic. Blood test.
How is the waste product filtered out during ultrafiltration?
Blood passing out the top of the nephron is under high pressure, so fluid is forced through the sieve-like capillaries into the bowman's capsule. It passes through three layers: glomerulus, basement membrane and bowman's capsule.
How is the transpiration rate affected by increased temp?
The warmer it is, the faster transpiration happens.
Water particles have more kinetic energy to evaporate and diffuse out of stomata in the atmosphere.