B4 Flashcards
What do arteries do
Carry oxygenated blood away from heart to your organs
What do veins do
Carry low oxygen blood from organs to your heart
What do capillaries do
Carry oxygen and glucose, small and thin walls to allow the substances to easily diffuse out your blood into cells
How do muscles and valves ensure blood is moved from the body towards the heart
The blood travels up veins into an area with two valves and the bottom valves close when enough blood as filled it and the muscle contracts to push the blood away to the heart from the organs
What does right ventricle do
Right ventricle pushes deoxygenated blood to the lungs in the pulmonary artery
What does left ventricle do
Pumps oxygenated blood around the body from artery called aorta
Why is muscle thicker on left ventricle wall
as allows it to resist the pressure needed to force oxygenated blood to rest of the body
What is a stent
It is a metal mesh placed in artery to deal with coronary heart disease
How does a stent work
A tiny balloon inflates to open blood vessel and stent, balloon deflates and removed but stent remains in place
What do statins do
To reduce risk of cardiovascular disease, they reduce blood cholesterol levels and slows down at which fatty material is deposited in coronary arteries
How does gas exchange system when breathing in
Atmospheric air at higher pressure than chest so drawn in , increased volume means lower pressure in chest, ribs move up and out, diaphragm flattens, volume of chest increases
How does gas exchange system work when breathing out
Pressure in chest higher than outside, decrease volume means increased pressure in chest, volume of chest get smaller, ribs fall and diaphragm moves up
Adaptions of alveoli
Large surface area, rich supply of capillaries, gas exchange happens in steepest concentration gradients
What do plant tissues do
Epidermal cover surfaces to protect them, secrete waxy substance to waterproof leaf. Palisade mesophyll contains lots of chloroplasts to carry out photosynthesis, spongy mesophyll has big space and large surface area to make diffusion of gases easier
What do plant tissues xylem and phloem do
Xylem carry water and dissolved mineral ions from root to leaves, phloem carry dissolved food from leaves to around plant
