Organisation Flashcards
what is the cell wall made out of?
Cellulose
what does the vacuole contain?
Cell sap
Name the single
celled organisms which produce the enzymes for bread making
Yeast
Where does Amylase work
Amylase works in the Mouth and Small Intestine
What is amylase involved in the digestion of
Starch to Glucose
Where does lipase work
Small Intestine
What is amylase involved in the digestion of
starch into sugars/glucose
Where does Protease Work
Small Intestine and Stomach
what is protease involved in the digestion of
Proteins into amino acids
Which gland produces all enzymes (lipase protease and amylase)
Pancreas
Describe the roles of the liver and the pancreas in the digestion
of fats.
The pancreas produces lipase which breaks down fats into fatty acids and glycerol. The liver produces bile which neutralises the acids which gives the most effective pH for the enzyme to work. Bile emulsifies Fats increasing the surface area for lipase.
what are enzymes
Enzymes are biological catalysts
Explain why enzymes are used in industry.
Brings about reactions at lower temperatures
Lower pressures
less expensive process
what do platelets do
platelets clot the blood at the site of the cut
a ventricle fills with blood by the contraction of ……
an atrium
when a ventricle contracts blood is forced into……
an artery
When a ventricle relaxes, the backflow of blood into it is prevented by the closing of
semi lunar valve
what is the red pigment found in red blood cells
haemoglobin
what is the function of the haemoglobin
carries oxygen from the lungs to the tissues
Describe one other way in which the structure of a red blood cell is different from the structure of a white blood cell.
red blood cells have bioconcave discs
State the name of the blood vessel that brings blood from the legs to the right side of the heart.
vena cava
Suggest two risk factors for coronary heart disease.
Smoking and high fat diet
Name the cells which control the size of the stomata
Guard Cells
Give one function of stomata.
allows carbon dioxide to enter
function of plasma
Transports the products of digestion
substances transported by the xylem
Water and Minerals
What is translocation
movement of dissolved sugar
Explain why translocation is important to plants.
sugars are made in the leaves (therefore) they need to be moved to other parts of the plant for respiration
Explain why active transport is necessary in root hair cells
for movement of minerals / ions against their concentration gradient
In a double blind drug trial, only some people know which patients have been given the drug. Who knows which patients have been given the drug?
Only scientists at the drug company
All enzymes are made of the same type of substance. What is this substance?
protein
Name
two
other substances transported in the blood plasma
carbon dioxide water glucose amino acids lactic acid
Explain why
having more red blood cells per cm3 of blood is an advantage to an athlete
more haemoglobin (therefore) more oxygen can be carried / transported (for) more (aerobic) respiration of muscle (cells)
what two blood vessels carry deoxygenated blood
pulmonary artery
vena cava
Compare the structure of an artery with the structure of a vein.
arteries have a thicker layer of muscle
arteries have a narrower lumen
arteries do not have valves
Describe how a student
could test cow’s milk to show whether it contains protein and
different types of carbohydrate.
Biuret reagent- tests for protein
add Biuret reagent to milk
solution will turn (from blue) to lilac if positive
iodine solution tests for starch
add iodine solution to milk
solution will turn (from orange / brown) to blue / black if positive
Benedict’s reagent tests for sugars
add Benedict’s reagent to milk and boil / heat (allow any
temperature above 60 °C)
solution will turn (from blue) to (brick) red / brown / orange /
yellow / green if positive
Explain why the indicator
in both tubes became colourless
lipase breaks down fat into fatty acids (and glycerol) (and) fatty acids lower the pH (and when) fatty acids cause the pH to be below 10 (the indicator becomes colourless
examples of diffusion
diffusion of oxygen and glucose into the cells of the body from the bloodstream
diffusion of carbon dioxide into plant cells
where is amylase produced
salivary glands
pancreas
small intestine
where is protease produced
stomach
pancreas
small intestine
where is lipase produced
pancreas
small intestine
The human lungs provide an exchange surface adapted for:
absorbing oxygen – needed for respiration – into the blood from the air
transferring carbon dioxide – produced by respiration – from the blood into the lungs then the air
Gaseous exchange
The exchange of gases occurs between the alveoli and blood in the capillaries that supply the lungs. Capillaries cover 70% of the outside of alveoli, providing a large surface area for gases to diffuse across.
how are the alveoli adapted to provide a very large surface area for gaseous exchange:
small size - each alveolus is a small sphere about 300 μm in diameter, giving it a larger surface area to volume ratio than larger structures
number - there are around 700 million alveoli – ie 350 million per lung
