Gas Exchange and Transport in Plants Flashcards
What does turgid mean
This is when the plant cell is full of water. This causes the vacuole to swell up and the cytoplasm pushes against the cell wall.
What is the xylem
Carries water and minerals up from the root
Is the xylem made of dead or alive cells
Dead
What is the phloem
Carries products of sucrose (food) away from the leaves. The content can travel up or down the plant to a food storage place.
What is the vascular bundle
This is were the xylem and phloem are grouped together in a young stem.
What are guard cells
These so round each stomata and become placid or turgid in order to open or close. At night the stomata will close as no photosynthesis will be occurring. This prevents the plant loosing water.
What is a potometer
A simple piece of apparatus which measures the rate of transpiration or the the rate of water uptake by a plant
What is the definition for active transport
This is were ions are moved from a low to high concentration through a semi permeable membrane by protein carriers. this requires energy in the form of ATP.
What is hydrocarbon ate indicator
This is used to show carbon dioxide concentration in a solution. It will go yellow to purple
High to Low
What is the word equation for photosynthesis
Carbon dioxide + water = oxygen + glucose
what is the symbol equation for photosynthesis
6CO2 + 6H2O = C6 H12 O6 + 6O2
What is the definition for respiration
Glucose from food is broken down to release energy and produce carbon dioxide + water
Where are the stomata found
On the underside of the leaf
What does hypertonic mean
Low water concentration.
Water moves out of the cell. Cytoplasm pulls away from the cell wall. The cell is plasmolyse.
What is Isotonic
Same water concentration as usual.
No net moment of water.
What does hypotonic mean
High water concentration.
Water moves into the cell. cytoplasm is pushing against the cell wall. The cell is turgid.
Why does the respiration rate never change
Because the levels of oxygen and carbon dioxide never change, so respiration can go at a constant rate.
What mineral ions does a plant need and what does it need them for
Magnesium is needed to make chlorophyll which is vital for photosynthesis.
Nitrates produce protein which is needed to make the plant grow.
Where does respiration take place
The mitochondria
Giv e two adaptions the root hair cell has and why
No chloroplast as there is no light
Lots of mitochondria for energy production
In the vascular bundle, are the xylem on the inside or outside of the phloem
Inside, bigger
How are the xylem and the phloem different
The xylem has a one way system as the water just needs to get up the plant. The phloem has two.
The phloem transports food substances, where as the xylem transports minerals.
Xylem cells are dead but the phloem’s are living
Xylem has thick cells (waterproof), the phloem has thin walls
Why does the phloem have companion cells
To help keep them alive by giving them food
What is the definition for transpiration
The evaporation of water vapour, out of the leaf, through the stomata.
What 4 factors affect the rate of transpiration
Temperature
Humidity
Wind
Light
How does temperature affect the rate of transpiration
More energy to evaporate the water from the stoma
Hoe does humidity affect the rate of transpiration
Shallower concentration gradient
How does light affect the rate of transpiration
Stoma open for photosynthesis
How do you set up a potometer
A stem is inserted into a potometer underwater and sealed so that there are no air leaks
A bubble is introduced into the side arm of the apparatus. The movement of this bubble is used to estimate the amount of water lost by respiration.
The rate of movement of the bubble over a fixed distance in a set time measured.
