animal.tissues,organs and systems Flashcards
what is the main function of the digestive system
to digest food andabsorb the nutrients obtained from digestion
what is the role of the pancrease and the salivary gland in the digestive system
the salivary gland and pancrease are glands which produce digestive juices containing enzymes
what is the role of the stomach in the digestive system
produces hydorchloric acid- which kills any bacteria present and provides the optimum acidic 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, which emulsifies lipids and allows lipase enzyme to work more efficiently
what is the role of the large intestine in the digestive system
Absorbs water from undigested foods. producing faeces
what is the role of enzymes in the digestive system
enzymes act as biological catalysts which,speeds up the rate of chemical reactions 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 reactionsin a cell or organism
what type of metabollic reactions do enzymes catalyse
.building larger molecules
.changing one molecule to another
.breaking down larger molecules into smaller molecules
what is the lock and key hypothesis of enzyme function
the shape of the enzyme active site and the substrate are complementry, so can bind together to form an enzyme-substrate complex
how does temperature affect enzyme action
increasing temp increases enzyme action,as molecules have a higher kinetic energy. above a certain temp, the shape of the active site is altered and the enzyme becomes denatured so it can no longer catalyse the reaction.
how does pH affect enzyme action
if the ph is to extreme,the shape of the active site may be altered and the enzyme may no longer work.
where are carbohydrates,proteases,lipase produced in the body
.carbohydrates=amylase-salivary gland,pancrease,small intestine
.proteases- stomach,pancrease,small intestine
.lipases- small intestine and pancrease
what is the role of carbohydrases in the digestive system
break down carbohydrates into monosocharides
Amylase breaks down starch into maltose,and maltase breaks down maltose into glucose
what is the role of proteases in the digestive system
proteases break down protiens 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 bring bigger molecules such as carbohydrates and protiens
where is bile made and stored in the digestive system
made by the liver and stored in the gallbladder
what is the role of bile in the digestive system
.bile is an alkaline substance which nuetralises the hydrochloric acid secreted by the stomach
.bile emulsifies liquids to form droplets.
what is the heart
an organ that pumps blood around the body
what is the purpouse of the circulatory system
carries oxygen and other useful substances to bodily tissues, and removes waste substances
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
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
makes the circulatory system more efficient,
how many chambers does the heart have and what are they called
they have 4
.right atrium
.right ventricle
.left atruim
.left ventricle
why is the wall of the left ventricle thicker
the left ventricle has to pump the blood at a higher pressure around the body
what are the four main blood vessels associated with the heart
.aorta-carries oxygenated blood from the heart to the body
.pulmonary vein-left =carries oxygenated blood from the lungs to the heart
.vena cava-right= carries deoxygenated blood from the body to the heart
.pulmonary artery= left- carries deoxygenated blood from the heart to the lungs
what is the purpouse of valves in the heart
prevent the backflow of blood
what is the purpouse of conorary arteries
supply the heart muscle with oxygenated blood
describe the process of blood flow through the heart
- blood enters the right atrium via the vena ceva, and the left atruim 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 vein and blood in the left ventricle enters the aorta
what is the appropriate value of the natural resting heart rate
70 beats per minute
how is the heart rate controlled
controlled by a group of cells in the right atrium , which act as a pacemaker.
they release waves of electrical activity , which cause the heart muscle to contract
what are the 3 types of blood vessels in the body
.arteries
.veins
.cappilaries
how can an abnormal heart rythm be treated
using an aritifical pacemaker, which sends out electrical signals to correct the hearts ryhthm
how are arteries adapted for their function
function- carry blood away from the heart
.thick muscle layer- adds strength the resist high pressure
.thick elastic layer-allows arteries to stretch and recoil, in order to withstand high pressure
how are veins adapted to their function
.function- carry blood towards the heart
.wide lumen-enables low pressure
.valves- prevent backflow of blood
how are capilaries adapted to theit function
.function- enable transfer of substances between the blood and tissues
.walls are one cell thick- short diffusion path
.permeable walls- substances can diffuse across
.narrow lumen-blood moves slowly-more time for diffusion
how would u calculate the rate of blood flow
volume of blood/number of minutes
where are the lungs found in the body
located in the thorax. they are protected by the ribcage and seperated by the rest of the abdomen.
what tissues and organs make up the gas exchange system
.trachea
.bronchi
.bronchioles
.alveoli
.Diaphram
explain how the lungs are ventilated by the action of intercostal muscles
.intercostal muscles contract
.ribcage moves upwards and outwards
.diaphram flattens and volume of the chest increases
.increases volume results in decrease pressure
.air is drawn into the lungs down pressure gradient \
the inverse occurs when air moves out the lungs
describe how gas exhange occurs at the alveoli
.oxygen diffuses from the alveoli into the capillary bloodtsream , down its concentration gradient.
.carbon dioxide diffuses from the capillary into the alveoli down its concentration gradient
describe how alveoli are adapted for gas exhange
. small and aranged in clusters- larger surface area
.rich blood supply- maintains concentration gradient
.thin alveolar wall-short diffusion pathway
how would u calculate the breathing rate
number of breaths / number of minutes
whih substance carries the different components of blood around the body
plasma
what substances are transported by plasma
.red blood cells
.white blood cell
.platelets
.carbon dioxide
.Urea
.products of digestion
what is plasma
A yellow liquid within blood that transports substances around the body
what is the purpouse of red blood cells in blood
transport of oxygen around the body
how are red blood cells adapted to their function
.bioncacave shape- increase surface area to volume ratio
.no nucelus- more room for heamolglobin to bind oxygen
.contain heamolglobin- binds to oxygen
what is the purpouse of white blood cells in blood
they form part of the immune system, which protects the body from invading pathogens
how are white blood cells adapted to their function
. have a nucelus - contains DNA which codes for protiens
.can produce antibodies
.can produce antitoxins
.can engulf and digest pathogens
what is the purpouse of plateletes in blood
platelets are small cell fragements which aid the clotting of blood at the site of a wound
why is the function of platelets important
. aid in the process of blood clotting. as a result red blood cells are trapped forming a plot which prevents excessive bleeding.
.scab formation, after the clot has dried, prevents bacteria from entering the wound
what is conorary heart disease
occurs when conorary arteries that supply the heart muscle become blocked with a buildup of fatty material.
-this restricts the supply of oxygen to the heart leading to heart attacks or death
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 removed to allow blood to flow freely.
what are the advanatges and disadvantages of stents
advantages=
.quick recovery time
.insertion can be carried out without general aenesthetic
.lower the risk of heard attack
disadvantages=
.risk of postoperative infection
.risk of blood clots at site of stent
what are statins
statins are drugs which reduce the level of bad cholesterol , which contrivutes to the developtment of conorary heart disease
advantages and disadvantages of statins
advantages=
.reduce risks of strokes,conoroary heart disease and heart attacks
.increase level of good cholestoral
disadvantages=
.have to be taken continously
.may have side effects
.effect may not be immiediate
what is a heart bypass surgery
a surgery where blocked conorary arteries are replaced with sections of veins taken 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 restless and die
what type of valves can replace leaky valves
.mechanical- made of metal or polymers
.biological- taken from animals
