B4 Organising Animals And Plants Flashcards
What is the function of xylem
It carries water and dissolved minerals from the roots to the leaves
What is the function of phloem
Carries dissolved food from the leaves around the plant
What are xylem and phloem
They are the transport tissue in plants
What is the function of epidermal tissue
Covers plants and protects them
What is the fuction of palisade mesophyll
Contains chloropasts for photosynthesis
What is Spongy mesophyll
Contains some chloropasts but has air space for diffusion
What are the features of meristem cells
Rapidly dividing can differentiate into any cell
What are plant organs made up of
Tissues such as epidermal, palisade mesophyll
State 3 plant organs
Root, stem and leaves form transport organ system
What is translocation
The movement of sugars in the plant
What is the role of the root hair cell
Absorbs water and minerals from soils adapted with a large surface area
What are the 4 steps of the transpiration stream
Stomata opens, water loss
Water vapour evaporates from the cells lining the air spaces
Water diffuses out through the stomata
More water is sucked up the xylem
What is the structure of blood plasma
Straw yellow liquid
What is the function of the blood plasma
Plasma transports many dissolved substances around the body
What is the structure of red blood cells
Very small in size. Has a large surface area to volume ratio
What is the function of red blood cells
To transport oxygen all over the body cells for respiration
What is the function of white blood cells
To fight diseases in the body
What is the function of platelets
They try to form blood clots to help seal wounds when skin is cut
What is the double circulatory system
The double circulatory system has two different circuits of blood. The right ventricle pumps blood to the lungs where gas exchange takes place. The left ventricle pumps blood around the rest of the body.
What is the function if the valves in veins
Valves prevent the backflow of blood
What type of blood do arteries carry
Oxygenated blood
What type of blood do veins carry
Deoxygenated blood
What is the function of capillaries
Allow fast diffusion of substances out of the blood into the body cells and tissues
What are the two top chambers of the heart called
Left and right atria
What are the two bottom chambers of the heart called
Left and right ventricles
What are the corony arteries
These are arteries that supply the heart with oxygen and glucose for respiration
What are the three main ways of treating heart disease
Drugs
Mechanical devices
Heart transplant
What is a stent
A wire mesh is inserted into a blocked coronary artery to widen the artery and allow more blood flow
What is an artificial valve
Valves in the heart that prevent the backflow of blood
Faulty heart valves can be replaced with biological or mechanical valves
What is a peacemaker
Electrical devices used to correct irregularities in the heart rate
What is tanspiration
Transpiration is the loss of water vapour from surface of the leaf
What is the function of stomata
They allow the exchange of gasses in and out of the leaf
Where is most of the stomata found
On the lower side of the leaf
How do mineral ions enter the plant
Mineral ions are dissolved in water in low concentrations. Therefore the mineral ions enter the plant via the root hair cells by active transport
What do guard cells have that helps them open and close
Guard cells have an unevenly thickened (cell) wall. This enables them to, change shape / bend when they gain water by osmosis.
What causes stomata to open
• Stomata opens during the day and closes during the night.
• High water potential outside the stomata
• Light causes stomata to open
What is the function of root hair cells
To absorb water and mineral ions by active transport
How do root hair cells adapt to absorb more water and mineral ions
They have many hairs to increase their surface area so the plant can absorb more water by osmosis
How does light intensity affect the rate of transpiration
Transpiration rate increases as light intensity increases
How does temperature affect the rate of transpiration
At higher temperatures the rate of transpiration increases
How does humidity affect the rate of transpiration
Transpiration rate is faster when conditions are less humid
What are the walls of xylem thickened with
Lignin
Where does photosnthesis take place
In the leaves of the plant
