2.5 the components of blood Flashcards
functions of the circulatory system:
- oxygen: lungs - cells
- carbon dioxide: cells - lungs
- nutrients: intestines - cells
- waste: cells - kidneys
- keeping your body at the right temperature
why is carbon dioxide carried to your lungs?
to be breathed out
why is waste carried to your kidneys?
to be removed
what happens to your blood after a little while?
(for example when the doctor takes a sample)
the blood naturally seperates into two large parts, with a small one in between
what are platelets?
not really cells, but tiny fragments of cells
so, if you put blood in a test tube and wait a little while - what will happen?
the blood will be divided:
- on the bottom - 45% red blood cells
- in the middle - >1% white blood cells and platelets
- on the top: 55% plasma
what are the two min components of blood?
plasma 55%
blood cells 45%
what’s plasma?
yellow liquid, mostly water
contains lots of dissolved parts:
- nutrients
- waste substances like carbon dioxide
- hormones
- oxygen
what the parts of blood?
red blood cells
white blood cells
platelets and plasma
where’s blood produced?
bone marrow of long bones (like femur)
how are red blood cells shaped, and how are they different from all other body cells?
disc shapes, and are different because they lack a cell nucleus
how does blood transport oxygen?
red blood cells contain a red substance called haemoglobin, which binds oxyegn
why does our blood have a red color?
because there are a lot more red blood cells than white blood cells. red blood cells have haemoglobin which makes them red
what is the color of blood when it is oxygenated, and what is it when it’s de-oxygenated?
oxygenated: bright red
de-oxygenated: deep red-purple
do white blood cells have nuclei? what do they fight?
yes they do. the fight bacteria, viruses and other invaders (which may cause disease)
how does your body react to invaders?
by making more white blood cells
what are the 2 types of white blood cells?
phagocytes
lymphocytes
what do phagocytes do?
change shape and stretch themselves to engulf and swallow bacteria, then digest the bacteria into small pieces that are no longer harmful
what do lymphocytes do?
make substances called antibodies, espeicially produced to assist the phagocytes in destroying invaders such as bacteria.
why do you get ill?
because it takes a while before your lymphocytes have made enough antibodies
what happens each time a new invader gets into your body?
a new antibodie is produced, specific for the invader. they surround and stick to the invader so that the phagocytes can engulf them
what will happen the next time the same invader enters your body?
the lymphocytes will remmeber how to make the specific antibodies much faster meaning your body is immune (to the invader). thus - you want get ill!
are platelets involved in blood clotting? (for example when the skin is cut)why?
yes, becase it is important to prevent the entry of invaders through the open wound
what can a clot prevent?
blood from flowing out of a punctured blood vessel for too long
