TOPIC B2 ORGANISATION Flashcards
what are organ systems
organisms working together to perform a specific function
what are similar cells organised into
tissues
define the term tissue
-a group of similar cells that work together to carry out a particular function
-it includes more than 1 type of cell
state 3 tissues in mammals
-muscular tissue, contracts to move whatever its attatched to
-glandular tissue, which makes and secretes chemicals like enzymes and hormones
-**epithethal **tissue. which covers some parts of the body e.g inside the gut
define the term organ
a group of different tissues working together to perform cetrain functions
state what the stomach is an organ made up of and why it needs these
-muscular tissue, moves the stomach wall to churn up the food
-glandular tissue, makes digestive juices to digest food
-epithelial tissue, covers the outside and inside of the stomach
what is an organ system
a group of organs working together to perform a particular function
state 5 organs in the digestive system
-glands
-stomach
-liver
-small intestine
-large intestine
why does the digestive system need glands
to produce digestive juices
why does the digestive system need the stomach
to digest food
why does the digestive system need the liver
to produce bile
why does the digestive system need small intestine
to absorb soluble food molecules
why does the digestive system need large intestine
to absorb water from undigested food, leaving faeces
state 1way to increase a chemical reaction
by raising temperatures
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 up of
-large proteins
-chains of amino acids
why do enzymes only catalyse one reaction
state 2things enzymes need for a reaction
-right temperature (an optimum one)
-right pH (neutral, 7)
state what must of happened for an enzyme to become denatured
-a high temperature increases the rate at first
-if it gets too hot, some bonds holding the enzymes together break
-this changes the enzymes active site so the subsrate will not fit anymore
what are enzymes used in digestion produced and released into
-produced by cells
-released into the gut to mix with food
what molecules need to be broken down by digestive enzymes
-starch, amino acids
-proteins, glycerol
-fats, fatty acids
smaller soluble molecules that pass easily through the walls
state the process of carbohydrates going into simple sugars
-carbohydrases
-e.g an amaylase as it breaks down starch
amylase made in 3 places
1. salivary glands
2. pancreas
3. small intestine
state the process of proteins going into simple sugars
-proteases converts proteins into amino acids
1. stomach
2. pancreas
3. small intestine
state the process of lipids going into simple sugars
-lipases convert lipids into glycerol and fatty acids
made in 2places
1. pancreas
2. small intestine
where is bile produced
-liver
-stored in gall bladder, b4 released into small intestine
-alkaline so it neutralises the acid
-makes digestion faster as it emulsifies fats
state the function of salivary glands
-produce amylase enzyme in saliva
state the function of liver
where biles produced
state the function of gall bladder
where biles stored before its released into the small intestine
state the function of large intestine
where excess waters absorbed from food
state the function of rectum
-where faeces are stored
state the function of stomach
-pummels food with muscular walls
-produces protease enzymes
-produces hydrochlonic acid to
1. kill bacteria
2. right pH for protein enzyme to work
state the function of pancreas
-produces protease, amylase and lipase enzymes
state the function of small intestine
-produces protease and lipase
what 2 tubes does the trachea divide into
-bronchi
-bronchioles
what does alveoli carry out in the body
-gas exchange
-lungs contain millions of air sacs that surround by networks of blood capillaries, where gas exchange happens
state where gas exchange happens
-in the lungs as they contain millions of little air sacs called alveoli
-theyre surrounded by a network of blood capillaries
state the process of alveoili
-blood passes next to the alveoli and contains lots of carbon dioxide and very little oxygen
-the oxygen diffuses out of the alveolus that has a high concentration into the blood, that has a low concentration
state how to calculate breathing rate
breaths per minute= number of breathes divided by number of minutes
what is the circulatory system made up of
-heart
-blood vessels
-blood
state the difference between the double circulatory system and the circulatory system
-double is just the 2circuits joined together
-humans have double
state what you would find in the 1st doulbe circulatory system
-a right ventricle that pumps deoxygenated blood to the lungs to take in oxygen
-blood then returns to the heart
state what you would find in the 2nd circulatory system
-a left ventricle that pumps oxygenated blood around all the other organs of the body
-blood gives up its oxygen at the body celld and deoxygenated blood returns to the heart and to the lungs again
state the role of the heart
-a pumping organ that keeps the blood flowing around the body
-walls are made up of muscle tissue
role of valves
to prevent the backflow of blood
step 1 of the 4 chamber process of the heart pumping blood around
1) blood flows into the 2atria from the vena cava and the pulmonary vein
step 2 of the 4 chamber process of the heart pumping blood around
atria contracts, pushing the blood into the ventricles
step 3 of the 4 chamber process of the heart pumping blood around
ventricles contract, forcing the blood into the ventricles and aorta and out the heart
step 4 of the 4 chamber process of the heart pumping blood around
blood flows to the organs through arteries and returns through veins
step 5 of the 4 chamber process of the heart pumping blood around
atria fills again and whole cycle restarts
what is the heart controlled by
a pacemaker
-a group of cells in the right atrium wall
-the cells produce small elecric impulses, causing them to contract
why is an artifical pacemaker often used
-to control heartbeat if the natural pacemaker cells dont work properly
or if the patient has an irregular heartbeat
state the 3 types of blood vessel
-arteries, carry blood AWAY from the heat
-capillaries, involved with the exchange of materials
-veins, carry blood TO the heart
how are the arteries adapted for its function
-walls are strong and elastic
-contain thick layers of muscle to make them strong
how are capillaries adapted
-thin wall only one cell thick which increases the rate of diffusion
-very small lumen
-permeable wall so substances diffuse in
-theyre tiny
how are the veins adapted
-blood is at a low pressure so walls dont need to be as thick as artieres
-bigger lumen than arteries to help blood flow
-valves to keep blood flow in the right direction
formula for calculating blood flow
-rate of blood flow= volume of blood divided by number of mintues
state the role of red blood cells
-to carry oxygen from the lungs to all the cells in the body
-biconcave shape, gives a large surface area for oxygen absorption
-no nucleus
-contain haemoglobin
what does haemoglobin become in oxygen
it binds to oxygen to become oxyhaemoglobin
-in body tissues the reverse happens and oxyahemoglobin splits up into haemoglobin and oxygen to release oxygen to the cells
white blood cells defend against
infection
-produce antibodies to fight microorganisms as well as antitoxins
state what helps blood clot
platelets
-small fragments of cells
-no nucleus
-help blood clot at a wound to stop blood pouring out and to stop microorganisms getting in
what is plasma
the liquid thar carries everything in blood
ex
-red +white blood cells
-platelets
-glucose
-carbon dioxide
-urea
