Biology B4 Flashcards
What is plasma
A yellow liquid in your blood thatthat transports all of your blood cells and other substances around the body
What blood cells do the plasma transport
Red blood cells, whiteblood cells and platelets
How much blood does the average person have in they’re body
4.7-5 litres
What other things do plasma transport
Waste carbon dioxide fromthe cells is carried to the lungs
Urea formed in your liver from the break down of protein is carried to your kidneys
What fo red blood cells do
They pick upoxygen from the air in your lungs and carry it to the cells where it is needed
How have red blood cells addapted to make them more efficient at they’re job
Biconcave diskswhich gives them an increased surface area for diffusion
They have a red pigment called haemoglobin that binds to oxygen
They nave no nucleus so there is more room for haemoglobin
What is the role of white blood cells
They form par tof oth bodys defence system.
Some (lymphocytes)produce antibodies and some form anti toxins
Some (phagocytes) engulf and digest bacteria and viruses
What are platelets
Small fragments of cells that help with blood cloting
What males up the human cirulatery system
Blood
Blood vessels
Heart
Arteries
Carry oxygenated blood away from the heartto the organs of the body
Viems
Carriy deoxygenated blood to the heart where it then goes to the lungs to get oxygen
Capillaries
Form networks connecting arteries and veins, they are extremely small
Features of arteries
Small lumen (high blood pressure)
Thick walls
Thick layer of muscle and elastic fibres
Features of veins
Thin walls
Large lumen (low blood pressure)
Often have valves
Features of capillaries
One cell thick walls
Tiny vessel with narrow lumen
Features of the heart
Coronary arteries Atria Vena cava Pulmonary vein Left and right ventricle Pulmonary artery Aorta Valves
What is a stent
A metal mesh that is put in the artery to unblock it by pushing the fatty deposits and holding the artery open
What is the role of the Vena cava
Brings deoxygenated blood into the right atrium
What do valves do
Keep the blood flowing in the right direction
Where does the pulmonary artery do
Takes the deoxygenated blood from the right ventricle to the lungs
What does the pulmonary vein do
Brings oxygenated blood from the lungs to the left atrium
What does the aorta do
Carries oxygenated blood round the body
What are statins
Medicine that doctors prescribe to lower cholesterol levels in the blood and reduce risk of coronary heart disease
What are the different features of the gas exchange system
Nose Mouth Trachea Bronchi Diaphragm Intercostal muscles Rib Lungs Heart Bronchioles Alveoli Abdomen
Where does gas exchange happen
The alveoli in the lungs
When you breath in what happens
Your alveoli fill with oxygen and it will diffuse in to the blood in a capillary running next to it. The CO2 will diffuse out of the capillary and that is what you breath out.
How have alveoli specialised to maximise diffusion
Big surface area
Thin walls
Good blood supply
Different parts of a plant
Waxy cuticle Epidermal tissue Palisade mesophyll tissue Spongy mesophyll tissue Xylem Phloem Stomata Guard cell
Epidermal tissue
Covers the whole plant
Upper is transparent to allow light to pass through to the palisade layer
Lower is full of little holes called stomata
Palisade mesophyll tissue
The part of the leaf where photosynthesis happens
Lots of chloroplasts
Spongy mesophyll tissue
Contains big air spaces to allow gasses to diffuse in and out of cells
Xylem and phloem
Transport things like water, mineral ions and food around the plant
Also help support the structure
Stomata
Small holes at the bottom of the plant that let CO2 diffuse directly into the plant
The opening and closing of it is controlled by guard cells
