(Module 4) Organising animals and plants Flashcards
What are the types pf blood cells
Red blood cell
White blood cell
Platelets
Name features of the liquid blood is carried in
Plasma It is yellow. Carries waste carbon dioxide Carries Urea formed in the liver Small soluble things from digestion are carried into it
Name factors of the red blood cell
Bi-concave for maximum surface area for diffusion
Full of a red pigment calle haemoglobin which attaches to oxygen
No nucleus for maximum oxygen/haemoglobin space
Name the blood vessels
Arteries
Veins
Capillaries
Factors of arteries
Carries blood away from the heart to the organs
The blood is red as it is oxidised
Arteries have thick walls containing muscles and electric fibres.
Blood is under extreme pressure - so when cut is very dangerous
The arteries stretches as the blood is forced through
Strong pulse
Factors of white blood cells
Bigger than red blood cells, but fewer of them
Contain a nucleus
Part of the body’s defence system
Some are lymphocytes:
They can form antibodies against microorganisms
They could make antitoxins against poisons made by microorganisms
Some are phagocytes:
Engulf and digest invading bacteria and viruses
Factors of veins
Carries blood away from the organs to the heart
The blood is low on oxygen and so is a dark purple colour
No pulse
Thinner walls
Valves to prevent back flow of blood
Blood is squeezed to the heart by the skeletal muscles
Factors of capillaries
Huge networks of capillaries connect veins and arteries at organs
Narrow with thin walls for diffusion
Many capillaries in one place for maximum diffusion
Receives carbon dioxide, glucose and oxygen
The double circulation system
In humans and mammals.
Blood is carried to heart by veins, away by arteries
Efficient
Not always veins and arteries
How is the heart fuelled
It is surrounded by muscles and is fuelled oxygen by the coronary arteries
Whey are stents required in a heart
Coronary heart disease
In the coronary arteries, there can be a build up of a fatty substance
So heart doesn’t get enough oxygen, so heart pain, heart attacks and death occur
How does the heart works as a pump
The two sides of the heart fill and empty at the same time
Blood enters the vena cava(on the right on a diagram, but looks like the left on paper)
Goes from right atrium to right ventricle
Out the pulmonary artery
Oxidised at the lungs
Brought back through the pulmonary vein
Through the left atrium and ventricle
Out the aorta
How a stent works
It is metal mesh over a tiny balloon
The ballon is threaded through the an artery until it is in the blocked area
The balloon is blown up to open the blood vessel and the stent at the same time
The balloon is deflated and removed, but the stent remains in place holding the blood vessel open
They can also release drugs to prevent blood clotting
Or the doctors can replace the blocked artery through bits of veins
Leaky valves in the heart and how they are fixed
Sometimes the valves in the heart stop working
So they are replaced by a metal one which last long, but clicks
Biological valves are sometimes used - last 12-15 years
Problems with the hearts pacemakers
The heart has a natural pacemaker monitoring its beats
If the natural one doesn’t work, it is switched with an artificial pacemaker
They are light, effective, and some even adapt to the bodies need e.g go faster even when not needed.
Why choose artificial hearts over donor hearts
When getting a donor heart, they need to be a tissue match. This is uncommon and many die waiting
Artificial hearts are not permanent
Factors of artificial hearts
Not permanent
Used whilst people wait for donor hearts or for their diseased heart to recover.
Need lots of machinery to work - most stay in hospital whilst having one
Technology is way off fully successful
How the gas exchange works
Oxygen enters the lungs through the trachea, through the bronchi to the bronchioles into the alveoli. They then enter the blood streams (capillaries) by diffusion
Adaptions of the Alveoli
Lots for a large surface area
Has a rich supply of capillaries, which maintains a concentration gradient in both directions
Blood coming to the lungs are low in oxygen and high in CO2 compared to inhaled air
Cells between capillaries and the air in the lungs are very thin for short distance
Very big surface area of the alveoli
Spherical shape allows large surface area
Plant tissues
Epidermal tissues: cover the surfaces
Palisade mesophyll: contains chloroplast
Spongy mesophyll: some chloroplast, but big air space and large surface area
Xylem: carries water and disolved minerals from the roots to the leaves
Phloem: carries disolved food from the leaves to the rest of the plant
Name 3 plant organs
Leafs
Roots
Tissues
Transport systems in plants (like veins and arteries)
Xylem: moving water and minerals
Phloem: moves food
Comparison of the phloem and xylem things
Phloem is made of living cells
Phloem carries food (sugars made by photosynthesis) from the leaves to the rest of the plant, especially to the stems and roots where the plant grows.)
The movement of the sugars is called translocation
Xylem carries water and minerals from the roots
Xylem mature cells are dead
Internal structure of the leaf
Waxy cuticle: water proof protective layer
Epidermal cell (upper epidermis): transparent layer, one cell thick, no chloroplast (to allow light to enter)
Chloroplast: traps sunlight energy
All above are in the palisade mesophyll layer:
Tightly packed cells, receives the most light
Xylem: transpiration (transports water and minerals)
Phloem: (translocation) transports food
Stoma: (like a pore) lots of stomata on the lower surface of the leaf
Guard cell: open and close the stoma (contains chloroplast for photosynthesis)
Some air space
All in that section are in the Spongy Mesophyll layer:
Air space for gad exchange (large surface area to volume ratio)
