lll Flashcards
describe breathing in
diaphragm and intercostal muscles contract
ribs move up and out diaphragm flattens
causes volume of thorax to increase
pressure decreases
so air is drawn into the lungs
describe breathing out
diaphragm and intercostal muscles relax
ribs move down and in diaphragm moves up
causes the volume of thorax to decrease
pressure increased
air is forced out of lungs
what 3 properties make alveoli efficient for gas transport
large surface area
good blood supply - steep concentration gradient
thin surface (one cell thick - short distance for faster diffusion)
what is the name for the upper part of the body
thorax
what is the name for the lower part of the body
abdomen
what are the veins
these carry blood ToWards the heart
what are the capillaries
these carry blood close to all Cells
what are the arteries
these carry blood Away from the heart
in bright light what happens to the eye muscles
- circular muscles contract
- radial muscles relax
- pupil constricts
in dim light what happens to the eye muscles
- circular muscles relax
- radial muscles contract
- pupil dilates
what is the Cerebral cortex
memory, consciousness, language and intelligence
what is the Cerebullum
coordination of all muscular activity
what is the medulla
Unconsciousness Activity - heart beat and breathing§
how does the eye focus on an image
the cornea bends (or refracts) light
the lens produces further refraction
an image is bought into focus on the retina
optic nerve carries nerve impulses to the brain
what and why is myopia
short sightedness
the eyeball is to long
cornea is too curved
light focusses in front of the retina
what and why is hyperopia
long sightedness
light focusses behind the retina
eyeball is too short
cornea not curved enough
how can myopia be fixed
concave lens
how can hyperopia be fixed
convex lens
Far Objects
ciliary muscles relax so lens is flatter and thinner
suspensory ligaments tighten
allows light to focus on retina
close objects
ciliary muscles contract so lens becomes fatter and wider
suspensory ligaments loosen
this allows light to focus on the retina
causes of type 2
body cells no longer respond to insulin
causes of type 1
pancreas fails to produce enough insulin
how is urine formed in the kidneys
- Filtration - The kidneys takes
Waste Products
other unwanted substances out of your blood
done by blood passing through the kidney
- selective reabsorption - useful substances are reabsorbed into the blood
- All of the Glucose
- Some of the water - rest is needed for osmosis
- Some of the ions - needed by the body by active transport
- Urea is not Absorbed - formation of urine - molecules that were not re-
absorbed
continue along the tubule as urine which passes down to be stored in the bladder
later to be released from the urethra
what happens in terms of ADH when you drink lots of water
brain produces more ADH
high volume of water reabsorbed by kidney
low urine output
water content normal
what happens in terms of ADH when don’t drink lots of water
brain produces less ADH
low volume of water reabsorbed by kidney
high urine output
water content normal
what uses does Auxins have
killing weeds
growing from cuttings with rooting powder
growing cells in tissue culture
what uses does gibberellin have
germination of seeds
can force a seed to germinate earlier than it should
and
encourage plants to flower
and
make fruit grow larger
what uses does ethene have
controls cell division and the ripening of fruits.
bananas are normally harvested before they are ripe so they can be transported long distances and stored until they are needed
ethene is used to trigger the bananas to ripen just before they are sold in the uk
