B1 - Organisation Flashcards
Amylase:
An enzyme produced in the salivary glands and pancreas that breaks
carbohydrates down into simple sugars.
Aorta
The main artery that takes oxygenated blood away from the heart to the body
Artery:
A blood vessel that carries blood at high pressure away from the heart.
Benign tumour:
An abnormal cell growth that is contained within one area and
does not invade other areas of the body
Bile
: A substance made in the liver and stored in the gallbladder which is used to neutralise stomach acid in the intestine and emulsify fats.
Blood:
: A tissue containing red blood cells, white blood cells, platelets and plasma.
Cancer
A non-communicable disease caused by changes in the cell that lead to
uncontrolled growth and division.
Capillary:
: A very thin blood vessel that is used for exchange of substances.
what is a Cell
The basic building block of all living organisms.
Communicable disease
A disease that can be spread between individuals either
directly or indirectly.
Coronary heart disease:
A disease caused by the buildup of fatty deposits
inside the coronary artery, narrowing it and reducing blood flow to the heart tissue.
Enzymes:
Biological catalysts that increase the rate of reactions in living organisms.
Health:
: The state of physical and mental wellbeing.
Heart:
An organ that pumps blood around the body in a double circulatory system
Lipase
An enzyme that is produced in the pancreas that breaks lipids down into
fatty acids and glycerol.
Lock and key hypothesis
: A theory that describes how substrates must be the correct
shape to fit the active site of an enzyme.
Malignant tumour:
A cancerous cell growth that invades neighbouring tissues
and can spread to different parts of the body in the blood.
Meristem tissue:
Plant tissues containing undifferentiated stem cells.
Metabolism
All of the chemical reactions occurring in an organism.
Non-communicable disease
A disease which cannot be spread between
individuals.
Organ systems
Groups of organs that work together to form organisms
Palisade mesophyll:
A tissue found in plant leaves that is specialised to carry out
photosynthesis.
Phloem
A transport tissue found in plants which is specialised to transport sugars from source to sink.
Protease
An enzyme produced in the stomach and pancreas that breaks proteins down into amino acids.
Pulmonary artery:
The main artery that takes deoxygenated blood away from the
heart to the lungs.
Pulmonary vein
The main vein that takes oxygenated blood back to the heart
from the lungs
Rate of reaction
The speed at which reactants are converted into products.
Spongy mesophyll:
A tissue found in plant leaves that is specialised for gas
exchange.
Statins:
drugs that are used to reduce blood cholesterol levels
Stent:
A tube that can be surgically implanted into blood vessels to keep them
open.
what is a Tissue:
A group of cells with a similar structure and function.
Translocation
: The movement of food molecules through the phloem tissue.
Transpiration:
The process of water evaporating from a plant.
Vein
A blood vessel that carries blood at a low pressure back to the heart.
Xylem
A transport tissue in plants which is specialised to transport water and
dissolved minerals from the roots of the plant to the leaves.
what is an organ
a collection of tissues working together to perform a certsin fucntion
how is epidermal tissue adapted for its function
epidermal tissue covers the entire plant.It has a waxy cuticle which helps reduce water loss from the leaf surface.
how is palisade mesophyll adapted for its function
palisade mesophyll tissues contain lots of chloroplasts which allows photosynthesis to progress at a rapid rate.
how is spongey mesophyll adapted for its function
spongey mesophyll tissue has lots of air spaces which allow gases to diffuse in and out
how is the xylem adapted for its function
1) made up of dead cells which forms a continuous hollow tube - allows the movement of mineral ions form the roots to leaves
2) strengthened by lignin - makes the vessel strong and waterproof
how is the phloem adapted for its function
1) cells have sieve plates that can connect them together - cell sap cn move through plate into another cell
2) made up of elongated living cells
what tissues does the leaf organ contain
1) epidermis
2) palisade mesophyll
3) spongey mesophyll
4)xylem
5) phloem
6) guard cells
what is the function of guard cells
guard cells control the opening and closing of the stomata
how are stomata adapted for their function
stomata allows gaseous exchange and water loss from the leaf
1) more stomata on the base of the leaf - minimises water loss
2) have guard cells which control opening and closing
how are root hair cells adapted for their function
root hair cells allow the uptake of water and mineral ions from the soil
1) large surface area - maximises rate of absorption
2) contains lots of mitochondria- release energy for active transport of mineral ions
what is translocation
the movement of dissolved sugars from the leaves to other parts of the plants
what is transpiration
transpiration is the evaporation of water vapour from the surface of the plant
how does transpiration work
1) water evaporates from the leaf surface via the stomata
2) water molecules cohere together - more water is pulled up the xylem in an unbroken column
3)more water is taken from the soil
how does temperate affect transpiration
increasing temperature increases rate of transpiration
higher rate of evaporation and diffusion of water
what is the role of the pancreas and salivary glands in the digestive system
the pancreas and salivary gland are glands which produce digestive juices containing enzymes
what is the main function of the digestive sysem
to digest food and absorb nutrients obtained from digestion
what is the role of the stomach in the digestive system
produces hydrochloric acid - which kills any bacteria present and provides the optimum acid PH for the protease enzyme to function
what is the role of the small intestine in the digestive system
the small intestine is the site where soluble food molecules are absorbed into the bloodstream
what is the role of the liver in the digestive system
produces bile(stored in the gall bladder) which emulsifies lipids and allows the lipase enzyme to work more efficiently
what is the role of the large intestine in the digestive system
absorbs water from undigested food, producing faeces
what is the role of the enzymes in the digestive system
enzymes act as biological catalysts which speed up the rate of biological reactions(the breakdown of food) without being used up
how does the shape of an enzyme affect its function
enzymes have a specific active site which is complementary to their substrate
what is metabolism
the sum of all the reactions in a cell or an organism
what type of metabolic reactions do enzymes catalyse
1) building large molecules to smaller molecules e.g. glucose to starch
2) changing one molecule to another
3)breaking down larger molecules to smaller molecules e.g. carbohydrates to glucose
what is the lock and key hypothesis of enzyme function
the shape of the enzyme active site and the substrate are complementary, so can bind together to form an enzyme -substrate complex
how does temperature affect enzyme action
increasing temperature increases enzyme action as molecules have a higher kinetic energy. Above a certain temperature the shape of the active site is alter and the enzyme becomes denatured ,so it can no longer catalyse the reaction.
how does pH affect enzyme function
the optimum pH for most enzymes is 7 (apart from protease in the stomach).If the pH is too extreme the shape of the enzyme may be altered and no longer work
where are carbohydrates, proteases and lipases produced in the body
carbohydrates : amylase - salivary gland and pancreas ; maltase - small intestine
proteases : pepsin - stomach ; other pancreas and small intestine
lipases : pancreas and small intestine
what is the role of the proteases in the digestive system
proteases break down protein into amino acids
what is the role of lipases in the digestive system
lipases break down lipids into fatty acids and glycerol
how are the products of digestion used
they are used to help build bigger molecules such as carbohydrates and proteins. Glucose is used as a substrate in respiration
where is bile made and stored in the body
bile is made by the liver and stored in the gall bladder
what is the role of bile in the digestive system
1) bile is an alkaline substance which neutralises the hydrochloric acid secreted by the stomach
2)bile emulsifies lipids to form droplets - this increases the surface area for the lipase enzyme to work
what is the heart
an organ that pumps blood around the body
what is the purpose of the circulatory system
carries oxygen and other useful substances to bodily tissues, and removes waste substances
how does the double circulatory system work
1) one pathway carries blood from the heart to the lungs - where the gaseous exchange of oxygen ad carbon dioxide takes place.
2)one pathway carries blood from the heart to the tissues
where does blood pumped by the right ventricle go
the lungs
where does blood pumped by the left ventricle go
body tissues
why is the double circulatory system important
it makes the circulatory system more efficient - for example ,oxygenated blood can be pumped around the body at a higher pressure by the left ventricle
how many chambers does the heart have ad what are they called
4 - right atrium ,right ventricle ,left atrium, left ventricle
why is the wall of the left ventricle thicker
the left ventricle has to pump blood at a higher pressure around the whole body
what are the four main blood vessels associated with the heart
1) aorta ( left ) - carries oxygenated blood from the heart to the body
2)pulmonary vein ( left ) - carries oxygenated blood from the lungs to the heart
3) vena cava (right ) - carries deoxygenated blood from the body to the heart
4)pulmonary artery (right) - carries deoxygenated blood from the heart to the lungs
what is the purpose of valves in the heart
prevent the backflow of blood
what is the purpose of coronary arteries
coronary arteries supply the heart muscle with oxygenated blood
describe the process of blood flow through the heart
1) blood enters the right atrium via the vena cava ,and the left atrium via the pulmonary vein
2)the atria contract, forcing blood into the ventricles and causing valves to shut
3)after the ventricles contract , blood in the right ventricle enters the pulmonary artery(to the lungs) and blood in the left ventricle enters the aorta(to the body)
what is the approximate value of tar natural resting heart rape
70 beats per minute
what is the approximate value of tar natural resting heart rape
70 beats per minute
how is the heart rate controlled
heart rate is controlled by a group of cells in the right atrium which acts as a peacemaker. They release waved of electrical activity which cause the heart muscle to contract
how can an abnormal heart rhythm be treated
irregular heart rhythms can be treated using an artificial peacemaker, which sends out electrical signals to correct the hearts rhythm
what are three types of blood vessel in the body
1) arteries
2)veins
3)capillaries
what are three types of blood vessel in the body
1) arteries
2)veins
3)capillaries
hoe are arteries adapted for their function
function : carry blood away from the heart
1) thick muscle layer - adds strength to resist high pressure
2)thick elastic layer - allows arteries to stretch and recoil - in order to withstand high pressure
how are veins adapted for their function
function :carry blood towards the heart
1) wide lumen - enables low pressure
2) valves - prevent backflow of blood
how are capillaries adapted for their function
function :enable transfer of substances between the blood and tissues
1)walls are one cell thick -short diffusion path.
2) permeable walls - substances can diffuse across
3) narrow lumen - blood moves slowly - more time for diffusion
how would you calculate the rate of blood flow
volume of blood / number of mins
where are the lungs found in the body
the lungs are located in the thorax(within the chest).they are protected by the ribcage and separated from the rest of the abdomen by the diaphragm
what tissues make up the gas exchange system
trachea , intercostal muscles , bronchi , bronchioles , alveoli , diaphragm
explain how the lungs are ventilated by the action of the intercostal muscles
1) intercostal muscles contract
2) ribcage moves upwards and outwards
3)diaphragm flattens and volume of the chest increases
4)increased volume results in decreased pressure
5)air s drawn into lungs down pressure gradient
describe how gas exchange occurs at the alveoli
1) oxygen diffuses from the alveoli into the capillary bloodstream down its concentration gradient .
2)carbon dioxide diffuses from he capillary into the alveoli down its concentration gradient
describe how alveoli are adapted for gas exchange
1) small and arranged in clusters - larger surface area
2) rich blood supply - maintains concentration gradient
3)thin alveolar wall - short diffusion pathway
what substance carries the different component of blood around the body
plasma
what substance are transported by the plasma
red blood cells , white blood cells , platelets , carbon dioxide , urea , products of digestion
what is plasma
a yellow liquid within the blood that transports substances around the body
what is the purpose of red blood cells in blood
transport of oxygen around the body
how are red blood cells adapted for their function
1) biconcave shape - increase surface area to volume ratio
2) no nucleus - more room for haemoglobin to bind to oxygen
3) contain haemoglobin - binds to oxygen
what is the purpose of white blood cells
they form part of the immune system , which protects the body from invading pathogens
how are white blood cells adapted for their function
1) have a nucleus - contains DNA which codes for proteins
2) can produce antibodies
3) can produce antitoxins
4) can engulf and digest pathogens (phagocytosis)
what is the purpose of platelets in blood
platelets are small cell fragments which aid the clotting of blood at the site of a wound
why is the function of platelets important
Platelets aid in the process of blood clotting. Scab formation prevents bacteria from entering the wound.
what is a stent and how does it work
a stent is a metal mesh tube that is inserted into a blocked artery so that it remains open. The stent is inflated using a balloon which is later removes to allow blood to flow freely.
what are the advantages and disadvantages of stents
advantages
1)insertion can be carried out without general anaesthetic
2)quick recovery time
3)lower the risk of a heart attack
disadvantages
1)risk of blood clots at site of stent
2)risk of infection
what are statins
statins are drugs which reduce the level of bad cholesterol which contributes to the development of coronary heart disease
what are the advantages and disadvantages of statins
advantages
1) reduce risk of strokes, coronary heart disease and heart attacks
2) increase level of good cholesterol
disadvantages
1)have to be taken continuously
2)may have side effects
3)effect may not be immediate
what is a heart bypass surgery
a surgery where blocked coronary arteries are replaced with section of veins from other parts of the body
what are the consequences of leaky heart valves
blood flows in the wrong direction, causing the heart to become less efficient. Patients may become breathless and die
what type of valves can replace leaky valves
mechanical - made of metal
biological - taken from animals
what are the advantages and disadvantages of mechanical valves
advantages
1)last for a long time
disadvantages
1) need to take medication to prevent blood clotting around valve
what are the advantages and disadvantages of biological valves
advantages
1)work well - no medication
disadvantages
1) only lasts 12-15 years
what is the purpose of an artificial heart
artificial hearts are intended to support a patients heart while they wait for a suitable donor heart
what are the advantages and disadvantages of artificial hearts
advantages
1) less likely to be rejected by immune system
2)allows damaged heart to rest to help recover
disadvantages
1)risk of infection due to surgery
2)risk of blood clots
what is health
health is the state of physical and mental wellbeing
what is a communicable disease
a disease cause by a pathogen which can be transmitted from one person to another
what is a non-communicable disease
a disease which can not be transmitted from one person to person e.g.cancer
how can diet affect health
too little food/lack of nutrition - vitamin deficiencies
too much food - obesity, type 2 diabetes
what is a risk factor
a risk factor is an aspect of a persons lifestyle or a substance found in the body or environment which can increase the risk of a disease
how do diet ,smoking and exercise affect development of cardiovascular disease
diet : high levels of bad cholesterol causes arteries to become blocked ,increasing blood pressure and risk of a heart attack
smoking: nicotine increases heart rate
exercise : lowers blood pressure, reducing strain on the heart
how does obesity affect the development of type 2 diabetes
obesity is strongly linked with the onset of type 2 diabetes- a disease in which the body stops responding to insulin
how does alcohol affect liver and brain function
1) increases risk of liver cancer
2) damages brain tissue and nerve cells
how does smoking affect the development of lung disease and lung cancer
1)tar in tobacco can damage the alveoli of lungs
2)tar also damages the cells which line the lungs leading to cell cancer
how do smoking and alcohol affect unborn babies
1) carbon monoxide from tobacco smoke reduces the amount of oxygen the foetus receives
2) alcohol passes across the placenta and damages the devolving foetus
what is cancer
cancer is the dveelopment of a tumor as a result of uncontrolled cell division
what is a benign tumor
1)a tumour that is contained in one location, usually within a membrane
2)they are not cancerous and do nor invade other parts of the body
3) can grow large very quickly - may cause damage to another organ
what is a malignant tumour
1) a tumour that can spread around the body via the blood
2)can invade other tissues
3)can divide more rapidly and have a longer lifespan
4) disrupts healthy tissues and may lead to death
