exchange and transport in animals Flashcards
why is it important for vital substance to be transported into organisms
to dispose of waste products
what are three examples of vital substances to be transported into organism to dispose of waste products
- plants take in carbon dioxide as it is crucial for photosynthesis and they get rid of oxygen because it is a waste products
- cells need oxygen for aerobic respiration, which CO2 as a waste product
- kidney efficiently removes waste such as urea and excess ions. if the excess urea is not removed, it will build up in the body and become toxic
what are exchange surfaces
specialised structures in living organisms where materials are transferred between organisms and its environment
what are three reasons why exchange surfaces are important
- efficient transfer of essential susbtances
- maintain of homeostasis
- support of key life processes like repsitration
what are four characteristics of efficient exchange surface
- large surface area - to maximise area for exchange
- thin walls - to reduce the distance that substances need to travel
- good blood supply - maintains good concentration gradients
- moist surface - facilitates diffusion of substances
what are three examples of exchange surfaces in living things
- the alveoli in the lungs are exchange surfaces for gases
- in the small intestine, the villi increase surface area for nutrient absorption
- in plants, the stomata in the leaves allows for gas exhcnage
what is a ratio
how big a value is compared to another
the larger the organism is ..
the smaller its surface area compared to the volume
how do you find the volume
length x width x height
what are the alveoli adapted for
gas exchange
in order for the alveoli to get the energy they need to function, what needs to happen
all our cells must carry out cellular respiration
what do you need for cellular respiration
oxygen
what is the role fo the lungs
to find the oxygen we need from the air around us into our blood stream where it can be transmitted to the body
what happens when you breathe in
- air passes throught our mouth/nose and then down the traachea
2.and from there divides between our two bronchi
3.and further divides between successive branch like structures called bronchiloes - once the air has made its way through all these branches it reaches these small sacs that are arranged like bunches of grapes , alveoli
alveoli are the site of…
gas exchange
adaptations of the alveoli
- made up of one larger layer of very thin cells - creates a short diffusion pathway + increase the rate at which co2 and o2 can diffuse across
2.large surface area - moist walls - allows gases to dissolve, this increases the rate of diffusion
what is the equation for breathing rate
number of breaths taken/ number of minites = BPM
when does your breathing rate change
when you exercise
when the blood in the capillaries return back to the lungs, what happens
the haemoglobin in the red blood cells will have already given u0p lots of urgency to the tissues which means that there wont be much left and because the alveoli is full of oxygen, they will have the perfect concentration gradient. the oxygen in the alveoli diffuses down that gradient into the blood and the cycle starts again . the co2 will be at a higher concentration than the alveoli which means it could easily diffuse across and once in the alveolii we can breath I out.throughout the whole process blood keeps on moving with a constant supply of deoxygenated blood entering the capillaries and oxygenated blood leaving it
what is carbondioxide carried by
it is dissolved in blood plasma
what is the equation for the rate of diffusion
surface area x concentration diffrence / thickness of membrane
what is the rate of diffujsion directly proportional to
the concentration gradinet
what is the rate of diffusion invesely proportional to
the diffusion distances
the larger the surface area and the concentration gradient….
the higher the rate of diffusion
the smaller the diffusion distance…
the faster the rate of diffusion
how many parts are there in the human blood
4
what is plasma
the liquid part of the blood
what can we find within plasma
white blood cells, red blood cells, platelets
what are platelets
tiny fragments of cells
what does plasma carry
- nutriets - eg glucose + ammino acids
- waste products - eg co2 and urea
- hormones, antibodies, antitoxins
what is the job of plasma
1.to transport dissolved susbstaances around the body
2. transpoers digestive product such as glucose to the small intestine and other major organs
3. transports co2 produced by aerobic respiration from the organs to the lungs to be breathed out
4. transport ure\ from the liver to the kidneys to be excreatedd in urine
what makes the blood watery so it can flow
plasma
what is the role of redblood cells
to transport oxygen from the lungs to the body cells so that our blood can use it for cellular respiration
what do redblood cells contain
hameglobian
where is oxyhameglobin made
the lungs
what two molecules combine to make oxyhaemglobin
haemoglobin and oxygen
what is hameoglobin
an oxygen carring molecule
adaptations of red blood cells
- no nucleus - more room for haemoglobin
- dimples in the centre of the red blood cell
- biconcave shape - larger surface area so oxygen can diffuse in and out more quickly
three examples of white blood cells defending against pathogens
- phagocytosis - where a white blood cell will consume a pathogen
- producing antibodies which bind to pathogens and help destroy them
- antitoxins which neutralises any toxins that the pathogens produce
what are white blood cells
part of the immune system
what do white blood cells contain
- nucleus
- dna in nucleus encodes the instructions the white blood cells need to do their function
do platelets have a nucleus
no
what is the role of the platelets
to help the blood to clot
how do platelets work
- float in the blood
- wait till there is a cut
- clot the area where clot is
what do platelets help to stop
- blood pouring out of us whenever we get a cut
- microorganisms from getting in because they could cause an infection
how much blood do adults have
5L
when the adult 5L of blood drop too low what do doctors do
give the patient new blood, there are two types : artificial or blood tranfusion
what happens if the 5L blood drops
there might not be enoug blood left over to deliver the required blood to their tissues
what is artificial blood
a blood substitute that consits of salt water
what does artificial blood do
add volume to our circulatory system which keeps the vessels full and allows the heart to keep pumping
what is a disadvantage to artificial blood
doesn;t have any red blood cells so it doesmt actually allow us to transport oxygen, can only replace 1/3 of our blood with ti
what is a more beneficial option than aritificla blood
blood transfusaion
what are the issues with using prodcuts from blood
- in a blood transfussion we have to make sure that the donated blood is the same as the patients blood
- immune system could reject the blood and the patient will die
- lots of different diseases can be transferred by blood
what is a blood transfusion
where a person is given real blood that has been donated by blood donors, which comes with its own red blood cells which is the key to serving bloiid
what are the three many uses of donated blood in medicine
- to replace blood lost in inury
- some people are giving platelets extracted from blood to help with clotting
- proteins extracted from blood can also be useful for example antibodies
what kind of circulatory system do we have
dounble circulatory system
how does blood travel to the heart
1.blood is pumped from the heart to the lungs where it collects oxygen
2. the blood then returns to the heart and is pumped around the whole body, where it delivers oxygen to the body cells
3. once the blood has passed through the organs, it goes back to the heart via the veins
4. the blood is travelling slowly and at low pressure . this means it could stop or go backwards