Flashcards in B5 the living body INCOMPLETE Deck (49)
what is the job of a skeleton?
to support the body and allow movement
it also protects vital organs
what animal shave an internal skeleton?
vertebrates, amphibians, reptiles, birds, mammals
what animals have an external organ?
what are the advantages of an internal skeleton/
it can grow with the body.
can attach to muscles
more flexible that external
gives body support and a framework
what are bones made-up of?
living cells, they can grow and repair themselves if the get damaged
what are long bones
big ones. they are hollow and thus lighter than solid ones. they are also stronger. they make movement more efficient
what is the hole inside bones filled with?
bone marrow. is makes new blood cels
what is the process of bones being made?
they start as cartilage in the womb, as you grow the cartilage is replaced by bone. blood vessels deposit calcium and phosphorus in the cartilage which eventually turns into bone THIS IS OSSIFICATION
what is osteoporosis?
when you are more prone to bone breakage due to not enough calcium in the bones, they are softer and can break more easily
why should you not move someone with a broken bone>
a it can injure nearby tissue
what is a synovial joint?
the main type in the body. they have ligaments holing them together with a high tensile strength. there is cartilage at the ends to stop rubbing. this also acts as a shock absorber. the synovial membrane releases synovial fluid to lubricate joints.
what is a ball and socket joint?
it can move in all directions and rotate, hip and sholder
what is a hinge joint?
can go backwards or forwards but not side to side. knee or elbow
what type of [air are muscles?
how does an arm bend?
is the bicep on top or underneath?
so triceps in underneath
BUY before you TRY!
how does an arm straighten?
where abouts in the body is the highest blood pressure?
what is a double circulatory system?
it has two circuits, one to the lungs the other to the rest of the body. they are separate
why do unborn babies not have a double circulatory system
they get their oxygen via the mother form the placenta. this means the blood doesn't have to travel to the lungs. they have hole in the hart( a gap between atria) t bypass the lungs in the system,
why do double circulatory systems have a high pressure?
having a high pressure allows materials to be transported around the body more quickly
how does the heart contract?
the cardiac cycle
what are the stages of a complete heartbeat?
1. blood flows into the artia
2. the atria contract pushing blood into ventricles
3. ventricles contract forcing blood into aorta and the pulmonary artery.
4. blood flows into arties, the atria fill again and they cycle starts all over again
what stops back flow of blood?
atria-ventricular and semilunar valves
what was galen theory on hearts?
arterial blood was made in the heart while blood in veins made in the liver
what did William Harvey say about the heart and blood?
the valves stopped back flow of blood
its a pump not a sucker
pulse caused by heart pumping blood into arteries
how does exercise lead to an increase in heart rate?
muscles need more oxygen to work so you breathe faster. your heart also pumps faster to deliver oxygen in the blood to muscles
how do hormones affect heart rate
it increases the rate. adrenaline is an example of this
what stimulates the atria to cntract?
the sino-atrial node SAN
what stimulates the ventricles to contract?
the atrial-ventriclar node AVN
how does the heart beat?
cells produce an electric current which spreads to surrounding muscle cells ad causes them to contract
what happens in one whole heartbeat?
the SAN produces current first which spreads to the atria. the current stimulates the AVN to produce a current which caused ventricles to contract. this process ensures the atria always contracts before the ventricles
what is a electrocardiogram? ECG
shows the electrical activity of the heart and heart attacks. shows irregular beats and general heath also
whats an echocardiogram?
an ultrasound f the heart. shows enlargments and pumping ability. also shows valve function
what is a hole in the heart?
a gap in the walls separating either the two ventricles or atria. allows blood to flow directly form one side to the other. deoxygenated and oxygenated blood mix. it can be corrected with surgery.
what is valve damage?
they can be weakened by heat attacks, infection or old age. it can cause high blood pressure as the valve doesn't open or close properly. blood doesn't circulate efficiently as blood can black-flow
what is coronary heart disease?
its when the coronary arteries supplying the heart with blood get blocked with fatty deposits. this reduces blood flow to the heart and often results in a heart attack/
can be treated with coronary bypass operations where a new artery is inserted to bypass the blockage
what is the advantage of using artificial parts in heart surgery?
rejections is not an issue. metals and plastics can be seen as foreign the same way tissue is.
how are blood clots formed?
a series of chemical reactions that take place when platelets are exposed to damages blood vessels
what can too little or too much clotting cause?
too little= may bleed to death
too much= causes strokes and deep vein thrombosis DVT
what is haemophillia?
a genetic condition where the blood doesn't clot easily because the clotting factor in the body is missing
what do the names of the blood groups refer to?
the type of antigens on the surface of the red blood cells
what drugs prevent the blood form clotting?
warfarin, heparin, aspirin
what is agglutination?
when the blood clumps
what is the criteria for organ donor
be relatively young so the organ is fit and healthy
be a similar body weight to the patient so organ fits
a close tissue maths to prevent rejection
living=over age of 18
how is rejection of organs dealt with?
the donor should have a similar tissue type.( a close tissue match)
immuno-suppressive drugs are also used. these suppress the patients immune system to help stop the organ being rejected. it does leave them vulnerable to infections thought.
what are the ethical issues with organ donation ?
some thing the body should be buried intact
others think life is up to god
others worry doctors might not save them if critically ill and their organs are needed for transplant. there is safe guarding to prevent this thought
worries people get pressured into being a living donor to relatives
examples of mechanical replacements for organs?
heart-lung machines to keep patients blood oxygenated
kidney dialysis machines to filter blood
mechanical ventilators to push air in and out of patients lungs