Topic 2- Organisation Flashcards
What is a cell?
The basic building blocks of all organisms
What are tissues?
Tissues are a group of cells with a similar structure and function, working together
What are organs?
A collection of tissues working together to perform a specific function
Describe the nature of enzyme molecules and relate their activity to temperature and pH changes.
As with many chemical reactions, the rate of an enzyme-catalysed reaction increases as the temperature increases. However, at high temperatures the rate decreases again because the enzyme becomes denatured and can no longer function.Changes in pH also alter the shape of an enzyme’s active site. Each enzyme work bests at a specific pH value. The optimum pH for an enzyme depends on where it normally works.
What are enzymes?
Biological catalysts,
Enzymes are proteins that help speed up metabolism, or the chemical reactions in our bodies.
equation for rate calculation:
Rate of reaction=
amount of substrate used or product former OVER
time taken
What is metabolism?
The sum of all the reactions in a cell or organism
What types of metabolic reactions do enzymes catalyse?
- Breaking down larger molecules to smaller molecules (carbohydrates to glucose)
- BUILDING smaller molecules into larger molecules
(Glucose to starch) - Changing one molecule to another
(glucose to fructose)
What is the lock and key hypothesis for enzyme function?
Enzymes have active sites on its surface
enzymes have active sites (the lock) which are in specific shapes, the substrate (the key) must fit into the active site for the enzyme to break it down into its products
How does temperature affect enzyme action?
Increasing emperature increases reaction rate, up until a certain point, (37), If the temp goes higher, the active site changes shape and the enzyme becomes denatured and cannot catalyse the reaction. this is same for ph
Where are carbohydrases, proteases and lipases produced in the body?
- carbohydrase- amylase (salivary gland, pancrease), maltase (small intestine)
- proteases-pepsin (stomach), others (pancrease, small intestine)
- lipases- pancrease and small intestine.
What role do carbohydrases play?
amylase breaks down starch into maltose
(Salivary gland, pancrease)
maltase breaks down maltose into glucose
(small inestine)
What role do proteases play in the digestive system?
Break down proteins into amino acids
What role do lipases play in the digestive system?
Break down lipids into fatty acids and glycerol
How are the products of digestion used?
glucose is used as a substrate in respiration.
to build bigger molecules to form carbohydrates and proteins.
Where is bile made and stored in the body?
Bile is made in the liver and stored in the gall bladder
What is the role of bile in the digestive system?
droplets
It is alkaline to neutralise hydrochloric acid from the stomach.
Bile emulsifies lipids to form droplets- this increases the surface area for the lipase enzyme to work on. (increasing the rate)
What is the purpose of the circulatory system?
carries oxygen and other useful substances to bodily tissues and remove waste products.
How does the double circulatory system work?
- One pathway carries blood from the heart to the lungs
- One pathway carries blood from the heart to the tissues
How do you test for carbohydrates, lipids and proteins?
- Benedict’s test for sugars
- iodine test for starch
- Biuret reagent for protein
investigate the effect of pH on the rate of reaction of amylase
enzyme.
To determine the rate of the amylase activity at different pHs. Students should use a continuous sampling technique to determine the time taken to completely
digest a starch solution at a range of pH values. Iodine reagent is to be used to test for starch
every 30 seconds. Temperature must be controlled by use of a water bath or electric heater.
https://www.bbc.co.uk/bitesize/guides/z9jrng8/revision/4
What is the purpose of the double circulatory system?
- one pathway carries blood from the heart to the lungs (where co2 and o2 exchange happens) (right ventricle)
- one pathway carries blood from the heart to the tissues. (left ventricle)
name the blood vessels associated with the heart
- aorta (oxygenated blood from heart to body)
- pulmonary vein (oxygenated blood from lungs to heart)
- vena cava (deoxygenated blood from body to heart)
- pulmonary artery (carries deoxygenated blood from heart to lung)
- coronary arteries
describe pacemakers
the natural resting heart is controlled by a group cells located in the right atrium that act as pacemakers.
artificial pacemakers are used to correct irregularities in the heart rate. A pacemaker signals the heart to beat when the heartbeat is too slow or irregular.
describe the structurs and function of arteries
Blood is transported in arteries, veins and capillaries.
Arteries:Always carry blood away from the heart.Carry blood under high pressure.Have thick muscular and elastic walls to pump and accommodate blood. a type of supporting tissue called connective tissue provides strength.the lumen (the channel) - is narrow
describe the function and structure of veins
always carries blood to the heart. dexoygenated blood except for pulmonary vein, carry blood under low or negative pressure, thin walls, less connective tissues than arteries, wide lumen
Describe the structure and function of capillaries
The capillaries connect the two types of blood vessel and molecules are exchanged between the blood and the cells across their walls. walls are just one cell thick. molecules can diffuse across.
The hearts full circulatory system
Deoxygenated blood flows in the RIGHT ATRIUM, moving through the vena cava to the heart valve to the right ventricle, to the pulmonary artery.
(blood from body to heart, then from heart to lungs)
Oxygenated blood flows in the LEFT ATRIUM, moving through the pulmonary vein to the heart valve to the left ventricle, to the aorta.
(blood from lungs to heart, then heart to body)
What tissues make up the gas exchange system?
- Trachea
- intercostal muscles
- bronchi
- bronchioles
- alveoli
- diaphragm
Adaptations for gas exchange
- large surface areaa allow faster diffusion of gases
- thin walls
- good ventilation with air so that diffusion gradient maintained
- good blood supply, dense capillary network
What are the functions of the ribs, intercoastal muscles, diaphragm?
Ribs- surround and protect the lungs, aid breathing
IM- muscles between the ribs, allow expansion and contraction to breathe
Diaphragm- sheet of connective tissue and muscle at the bottom of the thorax that help change the volume of the thorax
What are the functions of the trachea, bronchus, bronchioles and alveoli?
Trachea- windpipe mouth to nose to lungs, with cillia moving mucus up to the nose.
Bronchus- lets air in and out to breathe.
bronchioles- smaller tubes, split from bronchi
alveoli- tiny, moist, air sacs where gas exchange takes place, each alveolus covered in capillaries
Describe inhalation
- external IM contract
- Ribcage moves up and out
- Diaphraghm contracts and flattens
- volume of thorax increases
- pressure inside thorax decreases
- air is drawn in
Describe exhalation
- External IM relax
- ribcage moves down and in
- diaphragm relaxes, becomes dome-shaped
- colume of thorax decreases
- pressure inside thorax increases
- air is forced out
Describe how gas enchange occurs at the alveoli
- oxygen diffuses from the alveoli into the capillary blood stream down its concentration gradient
- carbon dioxide diffses from the capillary into the alveoli down its concentration gradient
Alveoli adaptions
- large surface area (small in clusters)
- rich blood supply
- thin wall (short diffusion pathway)
What is plasma?
a yellow liquid within blood that transports substances around the body
what substances are transported by plasma?
- red blood cells
- white blood cells
- platelets
- carbon dioxide
- urea
- products of digestion
How are red blood cells adapted?
- bioncave shape (increase surface area to volume ratio)
- no nucleus (more room for haemoglobin to combine to oxygen
- contains haemoglobin
White blood cells adaption
- have nucleus
- produce antibodies
- produce antitoxns
- can engulf and digest pathogens (phagocytosis)
platelets in the blood purpose
platelets are small cell fragments which aid the clotting of blood at the site of a wound
What is coronary heart disease?
Coronary heart disease occurs when the coronary arteries that supply the heart muscle become blocked with a buildup of fatty material.. restricting supply of oxygen to hearts, leads to heart attack
What are stents
metal mesh tube inserted unto a blocked artery to keep it open.
advantages and disadvantages of stents
A -quick recovery time -lowers risk of heart attack D -risk of postoperative infection -risk of blood clots at site of stent
What is a heart bypass surgery?
A surgery where blocked coronary arteries are replaced with sections of veins taken from other parts of the body.
What are the consequences of leaky heart valves?
Types of valves to replace leaky ones:
Blood flows in the wrong direction, (become breathless, death)
- Mechanical (metal)
- Biological (human or pigs)
Mechanical valves Advantages and Disadvantages:
A
-Long lasting
D
-Need to take medication to avoid blood clotting around valve
Biological valve Advantages and Disadvantages:
A
-Works well, no medication needed
D
-only lasts 12-15 years
Artificial hearts purpose and Advantages/Disadvantages
Temporary to keep patient stability until heart donor found.
A
- Less likely to be rejected by immune system
- Allows damaged heart to rest to help recovery
D
- Risk of infection due to surgery
- Risk of blood clots
- Have to take blood- thinning drugs.
What is health?
Health is the state of physical and mental wellbeing.
Communicable and non-communicable disease meaning:
Communicable- caused by pathogen that can be passed between organisms
Non-communicable- isn’t infectious, environment, inherited
How can health problems interact?
- Infection with certain viruses can lead to cancer
- weak immune system more likely for infection
- physical health can affect mental health
- immune reactions can trigger allergic reactions
What is a causal mechanism?
A mechanism which demonstrates how one factor biologically influences another
Diet, smoking, exercise effect development of cardiovascular diseases:
- smoking, nicotine increases heart rate
- diet, high cholesterol causes arteries to be blocked (increasing blood pressure, risk of heart attack)
- exercise, lowers blood cholestrol
How does alcohol effect liver and brain function?
- excessive use leads to liver scarring
- increases risk of liver cancer
- damages brain tissues and nerve cells
How does Tar in cigarettes effect you?
- can damages alveoli of the lungs
- damages cells in lining of of lungs leading to lung cancer
Smoking and alcohol effect on unborn babies:
- alcohol travels through placenta damaging developing foetus
- carbon monoxide from tobacco smoke reduces amount of oxygen baby gets causing still born or premature.
How do carcinogens (formation of cancer) affect the development of cancer?
ionising radiation is a type of carcinogen causing mutations in DNA potentially causing cancer
What is a benign tumour?
- tumour contined in one location, usually within a membrane
- can grow large quickly and affect organ
- cannot spread
What is a malignant tumour?
- can spread via blood or lymphatic system
- can invade other tissues
- disrupts health issues
