B2 - organisation Flashcards
The Thorax
The top part of the body
The abdomin
Lower part of the body
What separates the thorax from the abdomen
The diaphragm
Where does gas exchange happen
The alveoli
4 adaptations of the alveoli
- larger surface area
- moist lining - for dissolving gases
- good blood supply
- very thin walls - small diffusion pathway
How do you calculate breathing rate
Number of breaths
______________________
Number of minutes
Explain the transfer of oxygen and carbon dioxide between blood cells and body cells
Oxygen diffuses out from the blood cells into the body cells
Carbon dioxide diffuses out from the body cells into the blood cells
Explain the transfer of oxygen and carbon dioxide between the alveoli and blood cells
Oxygen diffuses out from the alveoli into the blood cells
Carbon dioxide diffuses out from the blood cells into the alveoli
How does the human body protect the lungs
Surrounded by pleural membranes and covered/ protected by ribcage
Function of the circulatory system
To get food and oxygen to every cell in the body and carry waste products like carbon dioxide and urea
2 waste products carried by circulatory system
Carbon dioxide and urea
3 examples of tissue and what they do( animsl£
- Muscular tissue - contracts to move
- glandular tissue - makes & secretes substances like enzymes
- epithelial tissue - covers some parts of the body
what tissues make up the stomach
Stomach
- muscular tissue
- glandular tissue
- epithelial tissue
what 5 organs make up the digestive system + what they do
Glands ( i.e pancreas & salivary glands)
- produce digestive juices
Stomach - where food is digested
Liver - produces bile
Small intestine - where food is digested and soluble food molecules are absorbed
Large intestine - where water is absorbed from undigested food
2 examples of glands and what they do in the digestive system
Pancreas and salivary glands
produce digestive juices
where is bile produced
the liver
small intestine
Where food is digested & soluble food molecules are absorbed into bloodstream
large intestine
Where water is absorbed from undigested food
theory used to explain function of enzymes
‘lock and key theory’.
2 adaptations of muscle tissue
- many mitochondria - energy for contraction
- special protein fibres which can change their length
purpose of muscular and glandular tissue in the stomach
- muscular tissue to churn food
- glandular tissue to release enzymes
3 main nutrients in food
- carbohydrates
- protein
- lipids
why must large molecules be digested
they are too large to be absorbed into the bloodstream and must be broken down
what happens during digestion (3)
- large molecules broken into smaller molecules by enzymes
- products of digestion absorbed into the blood stream
- products of digestion used to build new carbohydrates, proteins and lipids
steps of digestion (8)
- 1 food is chewed in the mouth + enzymes in saliva begin to digest starch into smaller sugar molecules
- 2 passes down the oesophagus into stomach + enzymes begin digestion of proteins + hcl in stomach also helps digest proteins
- 3 churning action of stomach muscles turns food into a fluid increasing surface area for enzymes to digest which passes into small intestine
- 4 pancreas releases enzymes that continue digestion of starch and proteins and starts digesting lipids
- 5 liver releases bile which neutralises stomach acid and speeds up digestion of lipids
- 6 in small intestine small food molecules are absorbed into the blood stream via diffusion or active transport
- 7 fluid goes to large intestine where water is absorbed
- 8 feces are released
enzymes in 2 words
biological catalysts
what are enzymes
large protein molecules with an active site on their surface where the substrate attaches to
how do enzymes break down molecules
- substrate fits perfectly into the active site as enzymes are specific
- enzyme breaks down substrate into the products
- ## if the substrate does not fit the the enzyme cannot break it down
what enzyme breaks down proteins
proteas
what are proteins
long chains of amino acids
what happens when we digest proteins
- protease enzyme converts protein back to the individual amino acids which are then absorbed in the bloodstream
- when amino acids are absorbed by body cells they join together in different order to make human proteins
what is starch
a chain of glucose molecules
what enzyme breaks down carbohydrates and starch specifically
carbohydrase breaks down carbs and amylase ( a type of carbohydrase) breaks down starch
what happens when carbohydrates are digested
we produce simple sugars
where is amylase found
- salivary glands
- pancreas
what is a lipid
a molecule of glycerol attached to three molecules of fatty acids
what enzyme breaks down lipids
lipase
what are lipids broken down to
glycerol and fatty acids
where is lipase found
- pancreas
- small intestine
what does bile do
help speed up reaction of lipids and neutralise stomach acid as it is alkaline ( note - not an enzyme )
how does bile speed up reaction of lipids
- bile emulsifies lipids (converts large lipid droplets into smaller droplets )
- this increases the surface area of lipid droplets
- increasing rate of lipid breakdown by lipase
what happens to enzyme activity as temperature increases
- rate of enzyme activity increases ( as the enzyme and substrate are moving faster - more successful collisions per second)
- continue to increase until enzyme reaches optimum temperature and works at fastest rate
- the activity will then rapidly decrease as the heat will cause enzyme to denature and the shape of the active site will change
issues with iodine test for starch
- only taking samples every 30 seconds meaning we only have an approximate time for reaction to complete
- solution - take samples at smaller interval i.e 10s
- colour change from orange to blue-black may not always be obvious as it tends to be gradual
- solution - have several ppl look at tile and decide when the reaction is complete
adaptations of small intestine for absorption
- long (around 5m) increasing surface area
- interior covered with millions of villi also increasing surface area
- microvilli on villi surface - surface area
- villi have good blood supply so bloodstream can rapidly remove products of digestion - increasing concentration gradient
- villi have thin membrane = short path
fish circulatory system
single circulatory system
- deoxygenated blood heart to gills oxygenated from gills to organs
Describe the human circulatory system
double circulatory system
- oxygenated from lungs to heart to organs
- deoxygenated blood from organs to heart to lungs
what separates the atrium from the ventricle
the valves
what is the heart
an organ consisting of mainly muscle tissue . pumps blood around the body made up of 4 chambers
where does the blood pass from heart to the lungs
the pulmonary artery
what type of blood passes from the lungs to the heart
oxygenated
how does blood get into the heart from the lungs
the pulmonary vein
what type of blood pumps from the heart to the body
oxygenated
what blood vesseldoes blood go from the heart to the rest of the body
the aorta
where does blood from the body enter the heart
the right atrium (deoxygenated)
where does blood from the lungs enter the heart
the left atrium (oxygenated)
describe the movement of blood in and out of the heart
- enters through the left (oxygenated) and right (deoxygenated) atriums
- the atria contract and the blood is forced into the ventricles
- ventricles contract and force blood out of the heart
-valves stop blood from flowing backwards into the atria when ventricles contract
-
what do valves do
prevent the backflow of blood
what side of the heart is thicker
the left side
what controls the natural resting heart rate
pacemaker cells in the right atrium
what can you do if pacemaker cells stop working
artificial pacemaker
active site
a region on an enzyme that binds to a protein or other substance during a reaction
metabolism
Metabolism is the term used for all the chemical reactions that go on inside an organism’s body. These reactions build up molecules, and break them down. They are controlled by enzymes
what ph conditions do stomach enzymes work best in
enzymes made in the stomach work best in acidic conditions.
what do digestive enzymes do
Digestive enzymes convert food into small soluble molecules that can be absorbed into the bloodstream.
what happens to the products of digestion
The products of digestion are used to build new carbohydrates, lipids and proteins. Some glucose is used in respiration.
where is bile produced and stored
Bile is made in the liver and stored in the gall bladder
what ph do enzymes in the pancreas work best in
The enzymes made in the pancreas and small intestine work best in alkaline conditions.
what ph do enzymes in the small intestine work best in
The enzymes made in the pancreas and small intestine work best in alkaline conditions.
digestive system
The digestive system is an example of an organ system in which several organs work together to digest and absorb food.
function of the heart
The heart is an organ that pumps blood around the body in a double circulatory system.
where does the right ventricle pump blood
The right ventricle pumps blood to the lungs where gas exchange takes place.
where does the left ventricle pump blood
The left ventricle pumps blood around the rest of the body.
5 blood vessels found in the heart
Aorta, vena cava, pulmonary artery, pulmonary vein and coronary arteries.
function of arteries and features
- Carry blood away from the heart.
- Carry high pressure blood so the artery walls have to be strong and elastic.
- They have thick layers of muscle for strength and elastic fibres for elasticity.
- They have a comparatively small lumen.
function of veins and features
- Carry blood away to the heart
- Carry low pressure blood so the vein walls can be thinner than an arteries.
- They have a large lumen to maintain blood flow.
- The lower pressure means that there’s a risk of backflow – veins have valves to keep the blood flowing in the right direction.
do veins or arteries have thicker walls - why
arteries have thicker walls as they carry high pressure blood away from the heart while veins carry low pressure blood
do veins or arteries have valves - why
veins have valves as lower pressure increases risk of backflow
function of capillaries
- Carry out exchange at tissues.
- tiny vessels with a very small lumen.
- They carry blood close to cells all over the body to enable an exchange of substances.
- They have extremely thin (1 cell thick), permeable walls to allow diffusion of substances.
blood
Blood is a tissue consisting of plasma, in which the red blood cells, white blood cells and platelets are suspended.
function of red blood cells
Needed to carry oxygen from the lungs to all of the cells in the body. They are produced in the bone marrow.
where are red blood cells produced
bone marrow
function of white blood cells
+ comparison with rbc
- White blood cells are needed to defend the body against infection by pathogens.
- They are much larger than the red blood cells, but they do have a nucleus and are also made in the bone marrow.
platelets
- Small fragments of cells which have broken off from large cells in the bone marrow.
- They play a really important role in blood clotting.
what happens during coronary heart disease
- In coronary heart disease layers of fatty material build up inside the coronary arteries, narrowing them.
- This reduces the flow of blood through the coronary arteries, resulting in a lack of oxygen for the heart muscle.
function of stents
Stents are used to keep the coronary arteries open.
functions of statins
Statins are widely used to reduce blood cholesterol levels which slows down the rate of fatty material deposit.
disadvantage of heart valves / risks
In some people heart valves may become faulty, preventing the valve from opening fully, or the heart valve might develop a leak.
2 solutions to faulty valves
Faulty heart valves can be replaced using biological or mechanical valves.
how do you treat heart failiar
In the case of heart failure a donor heart, or heart and lungs can be transplanted.
use of artificial hearts
Artificial hearts are occasionally used to keep patients alive whilst waiting for a heart transplant, or to allow the heart to rest as an aid to recovery.
health
Health is the state of physical and mental well-being.
3 factors affecting health
Other factors including diet, stress and life situations may have a profound effect on both physical and mental health.
risk factors
Risk factors are linked to an increased rate of a disease. They can be aspects of a person’s lifestyle and substances in the person’s body or environment.
cancer
The result of changes in cells that lead to uncontrolled growth and division.
benign tumor
Benign tumours are growths of abnormal cells which are contained in one area, usually within a membrane. They do not invade other parts of the body.
malignant tumor
Malignant tumour cells are cancers. They invade neighbouring tissues and spread to different parts of the body in the blood where they form secondary tumours.
5 things make up leaf tissue include
(Tech 6)
Plant tissues include:
* epidermal tissues
* palisade mesophyll
* spongy mesophyll
* xylem and phloem
* meristem tissue found at the growing tips of shoots and roots.
6 parts of the leaf
The leaf is a plant organ. Epidermis, palisade and spongy mesophyll, xylem and phloem, and guard cells surrounding stomata.
parts of plant organ system
The roots, stem and leaves form a plant organ system for transport of substances around the plant.
function of root hair cells
Root hair cells are adapted for the efficient uptake of water by osmosis, and mineral ions by active transport.
function of xylem
Xylem tissue transports water and mineral ions from the roots to the stems and leaves. It is composed of hollow tubes strengthened by lignin adapted for the transport of water in the transpiration stream.
function of stomata and guard cells
The role of stomata and guard cells are to control gas exchange and water loss.
function of phloem tissue
Phloem tissue transports dissolved sugars from the leaves to the rest of the plant for immediate use or storage.
translocation
The movement of food molecules through phloem tissue is called translocation.
what is the phloem composed of
Phloem is composed of tubes of elongated cells. Cell sap can move from one phloem cell to the next through pores in the end walls.
aim of food tests required practical
Conduct qualitative chemical tests for starch, reducing sugars, proteins, and lipids.
equipment for iodine test for starch
- Food sample
● A test tube
● Iodine solution (0.01 mol/dm3)
● Pipettes.
what chemical is used to test for starch
iodine
iodine test for starch method
- Put some of the food sample into a test tube.
- Add a few drops of iodine solution to the food sample using a pipette.
- If starch is present, the solution turns from brown to blue-black. Note any colour change in a
table of results.
equipment for benedict’s test for reducing sugars
- Food sample
● A test tube
● Benedict’s solution
● Hot water bath
● Thermometer
● Pipettes
what chemical is used to test for reducing sugars
benedict’s
method for benedict’s test for sugars
- Add an equal volume or excess of Benedict’s solution to the food sample in a test tube.
- Place in a hot water bath for a few minutes.
- If reducing sugar is present, a brick red precipitate is formed. If reducing sugar is absent,
the solution remains blue. Note any colour change in a table of results.
equipment for biuret’s test for protein
- A test tube
● A 10cm3 measuring cylinder
● Biuret solution
method for biuret’s test for protein
Add a few drops of Biuret’s reagent (sodium hydroxide and copper (II) sulphate) to the food
sample in a test tube.
2. Shake the solution to mix and wait for a few minutes.
3. If protein is present, the solution turns from blue to purple.
what chemical is used to test for protein
biuret
what colour does iodine turn if starch is present
blue-black (if not present remains orange)
what colour does benedict’s change when reduced sugars are present
brick red ( if not present remains blue)
what colour does biuret’s reagent change to when protein is present
purple (if not present remains blue)
equipment for emulsion test
- Food sample
● Test tube
● Ethanol
● Distilled water
emulsion test for lipids method
- Add a few cm3 of ethanol to the food sample.
- Pour this mixture into a test tube of equal volumes of distilled water.
- If lipids are present, a white emulsion is formed on the surface of the mixture.
- This is called the emulsion test.
what chemical is used to test for lipids
ethanol - emulsion test
how will the ethanol change when lipids are present
a white emulsion will form on surface
aim of enzyme rp
Effect of pH on the rate of activity of amylase enzyme
equipment for enzyme rp (12)
● test tubes
● water baths (electrical or Bunsen burners and beakers)
● spotting tiles
● measuring cylinder
● syringes
● a glass rod
● a stopwatch
● starch solution
● amylase solution
● buffered solutions
● iodine solution
● thermometer
