paper 1 - organisation✅ topic 2 Flashcards
What tissues does the stomach contain
muscular tissue and glandular tissue
What are fats also known as
lipids
What do enzymes do in the mouth
Enzymes in the saliva begin to digest the starch into smaller sugar molecules
What do enzymes do in the stomach
Enzymes begin the digestion of proteins
What is the benefit of the churning actions of the stomach muscles
Turns the food into a fluid increasing the surface area for enzymes to digest
What does the liver do in the digestion
releases bile , helps speed up the digestion of lipids by breaking them down into tiny droplets and increasing the surface area
also neutralises the acid released from the stomach to make conditions in small intestine alkaline the enzymes in small intestine work best in alkaline conditions
What enzymes break down proteins
proteases
Where is protease found
stomach
pancreas
small intestine
What does starch consist of
a chain of glucose molecules
What enzymes break down carbohydrates
carbohydrases (amylase)
Where is amylase made
in saliva , pancreas and small intestine
What does a lipid molecule consist of
a molecule of glycerol attached to three molecules of fatty acids
What enzymes digest lipid molecules
lipase
What do lipid molecules produce after being digested
glycerol and fatty acids
Where do we find lipase
pancreatic fluid and small intestine
Where is bile made and stored
made in liver stored in gall bladder
Bile emulsifies
the lipid
Bile is an
alkaline
As we increase the temperature tha activity of the enzyme
increase
Why as the temperature increases does enzyme activity increase ?
Because as the temperature increases the enzyme and substrate are moving faster so there are more collisions per second between the substrate and active site
Define optimum temperature
the enzyme working at the fastest possible rate
optimum temperature for human enzymes
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What happens to the enzymes at high temperatures using lock and key theory
the enzyme molecule vibrates and the shape of the active site changes.
becomes denatured
enzyme no longer catalyse reaction
What are the adaptions of the small intestine for increase absorption
• Long 5m - increase surface area
• Villi A massively increases surface area for the absorption of molecules
- villi has mitochondria energy for active transport
- thin membrane short diffusion path
- large blood supply increases concentration gradient
Why is the left side of the heart a thicker muscular wall
it needs to pump blood around the whole body so needs to use at a greater force
What is the purpose of the coronary arteries
to provide oxygen to the muscle cells of the heart
How do arteries cope with surges
they have elastic fibres which stretch
What happens when blood passes through capillaries
glucose and oxygen diffuse form the blood to the cells
carbon dioxide diffuse from cells back to blood
What increases diffusion in capillaries s
thin walls
What is the liquid part of the blood
plasma
What is the job of blood plasm
transport dissolved substances around the body
Where does plasma transport glucose from
small intestine to other organs
Where does plasma transport co2 form
organs to the lungs
Where does plasma transport urea form
liver to kidneys
What are the adaptions of red blood cels
• haemoglobin
• no nucleus - more room for haemoglobin
• bicojcave disc - greater surface area m, oxygen diffuses in and out rapidly
What are the key features of white blood cells
- contains a nucleus - contains DNA which encodes the instructions that the white blood cells need to do their job
what are the two cures for coronary heart diseases
stents and statins
What are statins
statins are drugs which reduce the level of cholesterol in blood
this slows down the rate that fatty material builds up in the arteriebs
What is the disadvantage of statins
• side effects - liver problems
What is a stent
a tube which can be inserted into the coronary artery to keep it open
An advantage of inserting a stent
blood can flow normally through the artery
a stent will not prevent other regions of the coronary arteries from narrowing
Disadvantage of stents
does not treat cause of disease
What can we do if heart valves are leaky
replace them with a mechanical valve made of metal or a valve from an animal
Advantage and disadvantage of mechanical valve
can last a long time
increase risk of blood clots
Advantage and disadvantages of animal valves
• may need to be replaced
• patients don’t need to take drugs
Define heart failure
heart cannot pump enough blood around the body
What can a patient be given while waiting for. a heart transplant
an artificial heart
Disadvantage of artificial hearts
increase risk of blood clotting
not log term solution
What prevents the trachea from
collapsing
rings of cartilage
What are the adaptations of alveoli to increase rate of gas exchange
• millions of alveoli - huge surface area
• thin walls - diffusion short
• very good blood supply - o2 rapidly removed , ensures concentration gradient is as steep as possible
What are the two different types of tumour
benign
malignant
define benign tumour
growths of abnormal cells, found in one area
usually contained within a membrane
do not invade other parts of the body
define malignant tumour
malignant cells invade neighbouring tissues and move into the bloodstream
once in the bloodstream malignant cells spread to the different parts of the body and form new tumours (secondary)
What cancers are linked to genetics
• certain breast cancer
•‘prostate cancer
• cancers of the large intestine
cancers linked to lifestyle
lung cancer - smoking
skin cancer - ultra violet light
mouth / throat cancer - alcohol
What is radon
radioactive gas increases risk of developing lung cancer
How does radon increase risk of developing lung cancer
releases ionising radiation which damages DNA in our cells.
Causes our cells to undergo uncontrolled cell division leading to cancer
define health
the state of physical and mental well being
What does it mean to have a defective immune system
more likely to suffer from infectious diseases
What can HPV cuase in some people
cervical cancer
What are the lifestyles factors that increase the risk of cardiovascular disease
• a diet high in fat and low in vegetables increase levels of certain types of cholesterol in the blood
• a diet high in salt can increase blood pressure
•smoking
What factors can effect unborn baby’s
• smoking - baby born with a low body mass
• drinking alcohol- fetal alcohol syndrome
How does water enter the roots
ROOT HAIR CELLS
What does the transpiration stream transport
dissolved mineral ions (e.g magnesium)
What does the stomata do in photosynthesis
it opens to allow carbon dioxide in, water vapor can now pass out the leaf
What happens to the guard cells during the day (high light intensity)
guard cells swell and change shape
this causes stomata to open
Under hot conditions what happens to stomata
plant closes stomata to reduce water loss by transpiration
(cannot photosynthesise)
Explain how amylase breaks down starch
Starch fits into active site
The substrate is specific to the active site, bonds with substrate
Which part of the blood transports glucose and water and carbon dioxide
plasma
What do protease convert proteins into
amino acids
What does amylase breaks down starch into
maltose
What does protease convert protease into
amino acids
What happens at the palisade mesophyll tissue
where most photosynthesis happens
what happens at the spongy mesophyll
contains big air spaces to allow gases to diffuse in and out of cells
What is the structure of the epidermal tissue
waxy cuticle - helps to reduce water loss by evaporation
explain the structure of the palisade layer
- lots of chloroplasts, near the top where they can get the most light
Describe the characteristics of a meristem tissue
found at the tips of the roots and shoots able to differentiate into lots of different types of plant cells , allowing plant to grow
Why is phloem tube made with smal pores
allow cell sap to flow through
Where does the transport go in the phloem tubes
both directions
lExpkin the structure of xylem cell
Made up of dead cells joined together end to end (1) With no end walls between them and a hole down the middle (1) it’ is stretched by lignin
Explain the structure of phloem
• mad elf columns elongated living cells with small pores in the end walls to allow cell sap to flow through
what’s cells sap
a liquid that’s made up of substances being transported
Where does phloem transport the dissolved sugars from
from leaves to rest of the plant
Where does xylem transport water and mineral ions
from roots to stem and the leaves
