Nerves And Hormones Flashcards
State the role of the nervous system in responding to the environment
To detect stimuli to coordinate our behaviour
Link some examples of stimuli and receptor cells
1) If there is a change in light we have light receptors in the eyes
2) If there is a change in smell we have chemical receptors
3) If there is a change in tough, pressure, temp or pain we have skin receptors.
4) If there is a change in position balance and sound we have sound receptor in you ears.
State some of the features of light receptor cells
Inside the light receptors you too types of cells and inside those you have nucleus, cell membrane and inside the cell membrane there is the cytoplasm.
Describe the pathway of a simple reflex action
For example a bee stings finger, stimulation of the pain receptor, impulses travel along the sensory neurone, impulses are passed along a relay neurone via a synapse, impulses travel along a motor neurone, via a synapse and when the impulse reaches the muscle in contracts.
Explain how water, ions, temperature and blood sugar levels are controlled
1) Water levels are controlled by sweating exhaling and through urine via kidneys.
2) Ions are controlled through sweating and some are lost through urine via kidneys as the kidneys can control the amount water is being lost though urine
3) Blood sugar are controlled through exercise and the amount of insulin as a hormone can control the amount of glucose stored in the liver if your no getting enough
4) Temperature is controlled through sweating and other ways to make body temperature about 37 degrees for enzymes
Describe the general role of hormones in the body
Hormones generally control blood sugar levels i.e insulin, control water levels, control the release of eggs and control growth.
Describe the role of hormones in controlling the menstrual cycle
FSH is produced in the pituitary gland and the job is to mature an egg. Oestrogen is produced in the ovaries and the role is to thicken the lining of the womb/uterus. LH is produced in the pituitary gland the job of LH is to release the egg
Explain the use of hormones in fertility
FSH will causes an egg to mature at the beginning of the cycle and stimulate the oestrogen to be produced. The oestrogen will inhibit the production of FSH. Oestrogen will stimulate the production of LH
Describe how plants are sensitive to light, moisture and gravity
Light- you have light shinning on the plant the plant will start to grow in the direction of the light, called phototropism.
Gravity- the shoot swing against the force of gravity called negative geotropism.
Moisture- The root will grow towards the force of gravity called positive geotropism
Explain how hormones can control growth in plants
A hormone called auxins in shoots encourages growth however in roots auxins inhibit growth.
Give some agriculture uses of hormones
Take a cutting form a plant dip it into some rooting compound and put it into the soil
Weed kiler has a high dosage of auxins which causes accelerated growth so rapidly that it causes the weed to die
