Chapter B4- Organising animals and plants Flashcards
haemoglobin
red pigment that carries oxygen around the body in the red blood cells
plasma
clear yellow liquid part of the blood that carries dissolved substances and blood cells around the body
red blood cells
biconcave cells that contain red pigment haemoglobin and carry oxygen around the body in the blood
white blood cells
blood cells involved in the immune system of the body.
engulf pathogens and make antibodies and antitoxins
platelets
fragments of cells in the blood that play a vital role in the clotting mechanism
urea
the waste product formed by the breakdown of excess amino acids in the liver
arteries and properties
- blood vessels that carry blood away from the heart.
- they usually carry oxygenated blood and have a pulse
- thick walls with muscle and elastic fibres
- narrow lumen
- dangerous if artery is cut
veins
- blood vessels that carry blood away from the heart
- usually carry deoxygenated blood
- have valves to prevent the back-flow of blood,
- wide lumen,
- thinner walls
capillaries
smallest blood vessels.
they run between individual cells and have a wall that is only one cell thick
double circulatory system
circulation of blood form the heart to the lungs is separate from the circulation of blood from the heart to the rest of the body
coronary arteries
blood vessels that supply oxygenated blood to the heart muscle
atria
upper chambers of the heart
vena cava
large vein that brings deoxygenated blood from the body into the heart
pulmonary vein
large blood vessel that carries oxygenated blood from the lungs back to the left atrium of the heart
ventricles
chambers of the heart that contract to force blood out of the heart
pulmonary artery
large blood vessel that takes deoxygenated blood from the right ventricle of the heart to the lungs
transpiration and what is involves
- loss of water vapour from the leaves of plants through the stomata when they are opened to allow gas exchange for photosynthesis.
- involves evaporation from the surface of the cells and diffusion through the stomata.
Function of blood
- transport oxygen and nutrients to your organs
- communication by carrying hormones
- homeostasis, carries waste products and spreads heat
- immune system, carries white blood cells and antibodies
what solutes are in blood
fatty acids + glycerol amino acids glucose minerals vitamins
types of blood cells and their function
- red blood cells- carry oxygen
- white blood cells- form our immune system
- platelets- clot blood at a wound
properties of red blood cells
- shape and structure- biconcave shape, small and flexible
- contain haemoglobin- a red protein that carries oxygen
artificial hearts
temporary heart to support natural heart
artificial heart advantages
-opportunity to live relatively normal life while waiting for a transplant
artificial heart disadvantages
- a lot of machinery
- you have to stay in hospital until transplant
- resources needed
- expensive
artificial pacemakers
electric device used to correct irregularities in the hearts rhythm
artificial pacemakers advantages
- sensitive to what your body needs
- increase in quality and length of life
artificial pacemakers disadvantages
regular medical checkups throughout your life
artificial pacemakers disadvantages
-regular medical checkups throughout your life
bypass operations
replacing the narrow or blocked coronary arteries with bits of veins from other parts of the body
bypass operations advantages
-they work for badly blocked arteries where stents can’t work
bypass operations disadvantages
- expensive
- risks associated with general anaesthetic
replacement heart valves
- mechanical valves are made of materials such as titanium and polymers
- biological valves are based on valves taken from animals or donors
replacement heart valves advantages
- mechanical lasts a long time
- biological work extremely well and no medication is needed
replacement valves disadvantages
- mechanical needs medication for the rest of your life
- biological only lasts about 12-15 years
stents advantages
- can be used all over the body
- releases drugs to prevent blood clotting
stents disadvantages
- benefits don’t justify the additional expense
- risks of general anaesthetic
what happens during inhalation
- ribs move up and out
- diaphragm flattens
- volume of chest increases
what happens during exhalation
- ribs fall
- diaphragm moves up
- volume of chest decreases
functions of outer muscles
contract pulling ribs up and out during inhalation
functions of inner muscles
contract pulling ribs down and in during exhalation
how does hot conditions affect the rate of transpiration
-more water evaporates from the cells and diffusion happens quicker, so increase rate of transpiration
how does dry conditions affect the rate of transpiration
water vapour diffuses more rapidly in dry air than in humid air, because concentration gradient is steeper
how does windy conditions affect the rate of transpiration
increases the rate of evaporation and maintains a steep concentration gradient from the inside of the leaf to the outside by removing water vapour as it diffuses out
stomata function
allow gases to move in and out of the leaf
big surface area function
gas exchange
waxy cuticle function
reduces water loss
air space function
added surface area
leaves function
carry out photosynthesis
stems function
support leaves and flower
roots function
take up water and minerals from the soil
