Organisation Flashcards
What is differentiation?
process by which cells become specialised for a specific job
What do specialised cells form?
tissues
What do a group of different tissues working together form?
organs
What is a tissue?
a group fo similar cells that work together to carry out a particular function.
Give examples of tissues?
muscular tissues
glandular tissues
epithelial tissues - inside of gut
What is an organ?
group of different tissues that work together to perform a certain function
Give examples of an organ?
stomach
liver
small intestine
What is an organ system?
a group of organs working together to perform a particular function
Give an example of an organ system?
digestive system
What are enzymes?
biological catalysts
What do living things have going on inside them?
different chemical reactions happing all the time
Why do we need enzymes?
reduce the need for high temperatures and they speed up the reaction
What is a catalyst?
a substance which increases the speed of a reaction, without being changed or used up in the reaction
What are enzymes made of?
enzymes are large proteins, proteins made up of chains of amino acids.
the chains fold into unique shapes which enzymes need to do their job
What do chemical reactions usually involve?
things being split apart or joined together
What does every enzyme have?
an active site which a unique shape that fits onto the substance involved in a reaction
Why do enzymes only catalyse for one specific reaction?
for enzyme to work the substrate has to fit into active site, if substrate doesn’t match active site then reaction went be catalysed
Why do enzymes need the right temperature?
at first increasing temp increases reaction, if too hot some bonds holding enzyme together break, changes shape of enzymes active site and substrate won’t fit - enzyme has become denatured
What do all enzymes have?
an optimum temperature they work at
How does the ph effect enzymes?
if too high or too low, ph interferes with bonds holding enzyme together, changes the shape of the active site and dentures enzyme
What is the optimum Ph for most enzymes?
Ph 7
Give examples of big molecules?
starch, protein and fats
What breaks the big molecules into smaller ones?
digestive enzymes
Why do molecules need to be small and soluble?
so that they can pass early through the wall of the digestive system, allowing them to be absorbed into the blood stream
what is amylase an example of?
carbohydrates
What do amylase do?
break down starch
What does amylase make after breaking down the substance?
maltose
Where is amylase made?
salivary glands, pancreas and small intestine
What do carbohydrases convert and into what?
converts carbohydrates into simple sugars
What do proteases convert and into what?
proteins into amino acids
Where are proteases made?
the stomach, pancreas, small intestine
What do lipases convert and into what?
lipids into glycerol and fatty acids
Where are lipases made?
pancreas and small intestine
Where is bile produced?
the liver
Where is bile stored?
gall bladder
Where is bile released?
the small intestine
What makes the stomach too acidic?
hydrochloric acid
What is wrong with the stomach being so acidic?
enzymes in small intestine can’t work properly
What does bile do?
- neutralises the hydrochloric acid and makes the small intestine alkaline so enzymes can work best
- emulsifies fats ( breaks them down into tiny droplets) so they have a bigger surface area of fat for the lipase to work on so digestion is faster
Where are enzymes in the digestive system produced?
glands and gut lining
How do you prepare a basic food test?
- break up piece of food using pester and morter
- add to a beaker and add some distilled water
- stir and dissolve some food
- filter solution with funnel and filter paper and get rid of solid bits of food
What do you use to test for sugars?
Benedicts solution
What are the two types of sugar?
non-reducing and reducing
explain how you can test for reducing sugars?
- transfer 5cm of food sample into test tube
- prepare water bath to 75 degrees
- add Benedicts solution
- place in water bath for 5 mins
- will change from blue to either green, yellow or brick red depending on strength of sugar
What do you use to test for starch?
iodine solution
Explain how to test for starch?
- transfer 5cm cubed of food sample into test tube
- add few drops of iodine solution and gently shake
- change from browny orange to black or blue-black
What do you use to test for proteins?
biuret solution
Explain how to test for proteins?
- transfer 2cm cubed of food into test tube
- add 2cm cubed of buret solution and mix by gently shaking
- from blue to pink or purple
What do you use to test for lipids?
sudan III
Explain the test for lipids?
- transfer 5cm cubed into test tube
- use a pipette to add 3 drops of Sudan III solution to test tube and gently mix
- will operate out into two layers, top layer bright red
Where are the lungs?
In the thorax
Where does the air you breathe through go through?
trachea
What does the trachea split into?
two tubes called bronchi
What do the bronchi split into?
smaller tubes called bronchioles
What do the bronchioles end at?
small bags called alveoli
What happens in the alveoli?
gas exchange
What are the alveoli surrounded by?
network of blood capillaries
Explain gas exchange in the lungs?
- gas next to alveoli has returned to lungs from rest of body, full ion CO2 and little oxygen.
- oxygen diffuses out of the alveolus into the blood
- carbon dioxide diffuses out of the blood into the alveolus to be breathed out.
What does the blood do with oxygen?
released from the red blood cells and diffuses into the body cells
What do body cells do with CO2
CO2 diffuses out the body cells into the blood to be carried to the lungs
How do you calculate breaths per minute?
number of breaths / number of minutes
What is the circulatory system made of?
heart, blood vessels and blood
Why is it the double circulatory system?
two circuits joined together
What happens in the first circuit?
right ventricle pumps deoxygenated blood to the lungs to take in oxygen, then returns to heart
What happens in the second circuit?
left ventricle pumps oxygenated blood to all other organs in the blood. Blood gives up its oxygen at the body cells and deoxygenated blood returns to heart to be pumped to the lungs
What are the walls of the heart made of?
mostly muscle tissue
What are the three types of blood vessels?
arteries, capillaries and veins
what is the main function of the arteries?
carry blood away from heart
What is the main function of the veins?
carry blood towards the heart
What is the main function of the capillaries?
involved with the exchange of materials at the tissues
Describe in detail the arteries?
- strong and elastic walls
- high pressure
- thick walls compared to the lumen
- walls have thick layers of muscle to make them strong and elastic fibres allow them to stretch and spring back
What is the lumen?
hole in the middle of blood vessels
Describe the capillaries?
- branch from arteries
- very very small
- carry blood close to every cell in the body to exchange substances with them
- permeable walls so substances can diffuse in and out
- supply food and oxygen
- take away CO2
- walls are one cell thick to increase rate of diffusion
Describe the Veins in detail?
- capillaries join up to them
- low pressure in veins so walls not so thick
- bigger lumen then arteries to help the blood flow
- have valves to ensure blood flows in one direction
How do you calculate rate of blood flow?
volume of blood / number of minutes
What do red blood cells carry?
oxygen
What is the shape of red blood cells?
biconcave shape meaning large surface area for absorbing oxygen
What do red blood cells not have?
nucleus, so can carry more oxygen
what do Red blood cells contain?
haemoglobin
Explain the role of haemoglobin?
In lungs, haemoglobin binds to oxygen to become oxyhemoglobin
In body tissues, oxyhemoglobin splits into haemoglobin and oxygen to release oxygen to cells
What is the main role of white blood cells?
defend against infection
Describe white blood cells in more detail?
- can change shape to engulf unwanted micro-organisms during phagocytosis
- some produce antibodies to fight microorganisms and antitoxins to neutralise toxins
- have a nucleus
What do platelets do?
help blood clot
Describe platelets in more detail?
- small fragments of cells
- no nucleus
- help blood clot and prevent blood pouring out and stop microorganisms getting in
- lack of platelets can cause excessive bleeding and bruising
What is plasma?
liquid that carries everything in the blood
What does plasma carry?
- red, white blood cells and platelets
- nutrients like amino acids and glucose
- CO2
- urea
- hormones
- proteins
- antibodies and antitoxins
What is cardiovascular disease?
diseases of the heart and blood vessels
What is the main role of stents?
keep arteries open
What is coronary heart disease?
when the coronary arteries that supply the blood to the muscle of the heart get blocked by layers if fatty material building up
This causes arteries to become narrow, blood flow is restricted and theres lack of oxygen to the heart muscle - causing a heart attack
describe stents?
tubes inserted inside arteries, keeping them open so blood canvass through to heart muscles.
They are a way of lowering the risk of a heart attack in people with coronary heart disease.
- effective for long time and the recovery time form surgery is quick
- complications from surgery + risk of infection
What is a blood clot near a stent called?
thrombosis
What do statins do?
reduce cholesterol in the blood
What is cholesterol?
an essential lipid that your body produces and needs to function properly, too much ( LDL cholesterol) can cause health problems
What does too much LDL cholesterol cause?
fatty deposits to form inside arteries, which can lead to coronary heart disease
What are statins?
drugs that reduce the amount of LDL cholesterol in the bloodstream , slowing down the rate of fatty acids forming
Advantages of statins?
- reduce risk of stroke, coronary heart disease and heart attacks
- can increase amount of beneficial cholesterol which can then remove bad cholesterol
- may help prevent other diseases
Disadvantages of statins?
- long term and must be taken regularly
- can sometimes cause negative side effects, storm cane be serious ( liver damage and memory loss)
- not instant effects, effects take time to kick in
If a patient has heart failure what may doctors perform?
a heart transplant
what are donor organs?
organs from people who have recently died ( may not be available or suitable at that time)
What are artificial hearts?
mechanical devices that pump blood for a person whose own heart has failed
- usually only a temporary fix to keep alive until donor heart is available
- can be permanent
What are the advantages of artificial hearts?
- less likely to be rejected by humans immune system , then donor heart as made of plastic or metal so body doesn’t recognise them as foreign cells
What are the disadvantages of Artificial hearts?
- surgery can lead to bleeding and infection
- doesn’t work as well then a healthy natural one
- parts of heart could wear out, electric motor could fail
- blood doesn’t flow through as smoothly, which can cause blood clots
- patient has to take drugs
What can faulty heart valves be replaced with?
biological or mechanical valves
How can the valves in the heart be be damaged or weakened?
heart attacks, old age, infection
What does damage to a valve cause?
- valve tissue may stiffen, so won’t open properly
- valve may become leaky, allowing blood to flow in both directions
How can secure valve damage be replaced?
- replacement valves from humans or mammals - biological valves
- man made valves - mechanical valves
What can artificial blood do?
keep you alive in an emergency
What is artificial blood?
a blood substitute, which is used to replace the lost volume of blood - can keep someone alive and give them time to produce new blood cells, if not need a blood transfusion
What is health?
the state of physical and mental wellbeing
What are the two types of disease?
communicable and non-communicable
What is a communicable disease?
are those that can spread from person to person or between animals and people. caused by: - bacteria - viruses - parasites -fungi
What are non-communicable diseases?
those that cannot spread between people or between animals and people. Last for a long time and get worse slowly
What can different types of diseases sometimes do?
interact and cause other physical and mental issues that don’t immediately seem related
What do people who have problems with their immune system have an increased chance of suffering from?
communicable diseases such as flu because their body is less likely to defend itself against the pathogen that causes disease
what can viruses living in cells be a trigger for?
cancer, a viral infection can develop into cancer
What can immune system reactions in the body caused by an infection of a pathogen sometimes trigger?
allergic reactions such as skin rashes or worsen the symptoms of asthma for asthma sufferers
What can mental health issues like depression be triggered by?
severe physical health problems.
What are some other factors that can affect your health?
- diet
- stress you are under
- life situation ( access to medicines, healthy food, contraception)
What are risk factors?
things that are linked to the increase in the likelihood that a person will develop a certain disease during their lifetime
What are many non- communicable diseases often caused by?
risk factors interacting with each other rather then one factor alone
What type of impacts can lifestyle factors impact?
locally, nationally, internationally
Give examples of some risk factors that are able to directly cause a disease?
- smocking as it damages the walls of arteries and cells in lining of lungs
- obesity can directly cause type 2 diabetes as the body becomes less sensitive to insulin
- drinking too much alcohol, can effect brain function as it damages nerve cells in brain
- smoking when pregnant can cause health problems for baby
- cancer can be directly caused by radiation or exposure to some substances
What can non-communicable diseases be?
- very costly, some companies may have to move or adapt their home for person with disease
- loss of income if person dies
What is cancer caused by?
uncontrolled cell growth and division
What is uncontrolled cell growth and division a result of?
changes that occur to the cells and result in the formation of a tumour
What is a tumour?
mass of cells
What are the two types of tumour?
benign or malignant
what is a benign tumour?
- when tumour grows until there is no more room
- tumour stays in one place rather then invading other tissues.
- isn’t dangerous type ands tumour isn’t cancerous
What is a malignant tumour?
- tumour grows and spreads to neighbouring tissues
- cells can break off and spread to other parts of body through blood stream
- malignant cells invade and form secondary tissues
- canerous
- very dangerous
What are the risk factors associated with cancer?
- smoking ( lung cancer)
- obesity ( bowel, liver and kidney cancer)
- UV exposure ( skin cancer
- viral infection ( liver cancer)
How else can you develop cancer?
genetics
Which genes have been linked to increase likelihood of breast and ovarian cancer?
BRCA genes
