Paper 2 Extra 2 Flashcards
Difference between blood flowing through pulmonary artery and aorta
blood in pulmonary artery is deoxygenated and has lower pressure
How is vena cava different to aorta?
vena cava has lower pressure, deoxygenated blood, greater conc of carbon dioxide and darker red blood
What produces progesterone?
Corpus luteum
How are blood cells adapted?
The blood vessel has thick walls/small lumen to carry oxygenated blood under high pressure.
What does oestrogen inhibit?
FSH
What sticks out of hairs?
Sebaceous
What does low progesterone cause?
FSH to be released
Function of stomata
Gas exchange and for water vapour to leave
What is top layer
Upper epidermis
difference between normal leaf and xerophyte?
leaf becomes a spine / reduced surface area (1) • (waxy) cuticle is thicker (1) • stomata are sunk in pits / fewer stomata /smaller stomata (1) • leaf is rolled / curled leaves(1) • guard cells / stomata close during the day
Describe the route taken by urine from the kidney until it leaves the body
(travels from the kidneys) through the ureters (1)
• to the bladder (where it is stored)(1)
• (from the bladder) through the urethra (and out of the body
Where are amino acids broken down into urea?
The liver.
Where do ova mature?
In the follicles
Why does the corpus luteum produce progesterone around day 20?
To maintain the lining of the uterus
Explain why taking high levels of oestrogen and progesterone in the combined
contraceptive pill reduces the chance of pregnancy
to inhibit the production of FSH (1) • to prevent eggs maturing (1) OR • to inhibit the production LH (1) • so ovulation is prevented (1)
What diffuses with alveoli ?
Capilaries
Are arteries wide/
No
Are veins wide?
Yes.
Explain why there are differences in the concentrations of some components
in the blood and some components in this part of the nephron.
{red blood cells/ white blood cells / proteins} {are
not present in the filtrate / cannot be filtered into
the nephron} (1)
• because they are too large to pass {through the
membrane/into the nephron} (1)
OR
• glucose is found in the filtrate (1)
• because it is small enough to pass {through the
membrane / into the nephron} (1)
Why is a coverslip used to place on top of the leaf?
keep leaf peel flat (1)
• keep leaf peel in place (1)
• protect the (objective) lens (1)
• protect the specimen (1)
explain why the leaf peel rather than the whole leaf was viewed with a microscope
the leaf peel is thin / leaf is too
thick (1)
• as the leaf peel allows light to
pass through it/the leaf would
not allow light to shine through it
(1)
• to enable the {stomata / cells/
guard cells} to be identified (1)How do guard cells take in water?
Through osmosis.
Explain why it is an advantage to the plant to have this distribution of stomata
in the upper and lower surfaces of the leaf.
• no stomata (in the upper surface) to reduce water loss (1) • water loss during transpiration / evaporation (1) OR • stomata (on the lower surface) allow gas exchange (1) • gas exchange is needed for photosynthesis (1)
) Explain why there is a change in the rate of blood flow through the digestive
system during exercise.
there is increased blood flow to
the muscles (1)
• to allow for { respiration/
release of energy} (in the
muscles) (1)The stroke volume is the amount of blood leaving one chamber of the
heart per beat.
From which chamber of the heart does this volume of oxygenated blood flow?
Left ventricle
When an iguana is too hot, it pants by opening its mouth to cool down.
Explain how this behaviour helps to cool the iguana down.
• (panting) causes water loss (1)
• causing evaporation / removal of latent heat (so
reduction in temperature)
) Explain the role of vasodilation in thermoregulation
vasodilation acts to cool the body down (1) • more blood flows near the surface of the skin (1) • less blood flows through the shunt valve (1) • causing increased thermal energy loss (
Transpiration
- the movement of water
- from the root through the plant
- through the lignified cells/dead cells
- of the xylem
- driven by evaporation of water from the leaves
- through the stomata
- flow is only in one direction
- by capillary action
- according to the cohesion-tension theory
Translocation
the movement of sugars from the leaves • through the plant • as sucrose • through the living sieve cells • of the phloem • flow is bidirectional • to sinks in the plant where the sucrose is needed
Explain how clomifene therapy may increase the chance of a woman over the
age of 50 becoming pregnant.
causes the release of FSH (1) • stimulating eggs to develop (in the follicles/ovary) (1) OR • causes the release of LH (1) • stimulating ovulation (1)
Explain how the release of adrenalin can result in the improved performance of
an athlete.
adrenalin acts to increase heart
rate / blood pressure (1)
• so there is increased blood flow (1)
• causes the release of glucose from
glycogen (1)
• so increased {oxygen/glucose} (1)
• increased the rate of respiration (1)
• to release energy (for the
working muscles/body) (1)Variables auxins
Direction of light.
Grass flexible
So does not break in windy conditions
why is leaf rolled
to trap air inside
what does stomata cause
Water loss
What do hairs on lower surface do
Reduce air movement
