Plant Structures and their functions Flashcards
In what part of a cell does photosynthesis take place?
Chloroplasts
Apart from water vapour, what gas is needed for photosynthesis?
Carbon dioxide (CO2)
Name the two products of photosynthesis
Glucose and Oxygen
Why is photosynthesis described as an endothermic reaction?
Because it takes in energy to make the reaction work
What effect would a low carbon dioxide concentration have on the rate of photosynthesis?
It would slow down the reaction
What effect would a temperature above 45C usually have on the rate of photosynthesis?
It would make the reaction slow or stop as plants cannot photosynthesize at high temperatures
What is the relationship between light intensity and distance from a light source?
Light intensity = 1/distance(d)2
What is the relationship between light intensity on the rate of photosynthesis?
The higher the light intensity, the higher the rate of photosynthesis.
What is a limiting factor?
A limiting factor is a factor which limits the rate at which a chemical reaction occurs
What are the limiting factors for photosynthesis?
Amount of carbon dioxide, light intensity and temperature.
What does the relationship between temperature and rate of photosynthesis look like on a graph?
The rate of photosynthesis would increase up to a certain point and then begin to drop down to 0
What does the relationship between amount of carbon dioxide and rate of photosynthesis look like on a graph?
The rate of photosynthesis would increase up to a point and then form a plateau
What does the relationship between light intensity and rate of photosynthesis look like on a graph?
The rate of photosynthesis would increase up to a point and then form a plateau
How are root hair cells adapted to their function?
They have a large surface area to absorb water and nutrients
By what process do phloem tubes transport sucrose around a plant?
Active transport
Describe the structure of xylem vessels
Xylem vessels are long hollow chains of tough long dead xylem cells.
What are stomata?
Tiny pores on the surface of a plant, found mostly on the underside of the leaves
What is the role of stomata in transpiration?
They allow the water vapour to escape from the plant
Give three factors that affect the rate of transpiration
Light intensity, temperature and air flow.
What can you use to measure the rate of transpiration?
Potometer
Calculate the rate of transpiration if the distance moved by the bubble is 50mm and it took 20seconds to move.
2.5mm/sec-1
Name, in order from top to bottom, the layers of a leaf.
Waxy Cuticle Upper epidermis Palisade mesophyll tissue Spongy mesophyll tissue Lower epidermis Waxy Cuticle
Which layer has the most choloplasts?
Palisade mesophyll tissue
Name 3 adaptations that plants have to live in desert conditions.
Small leaves or spines Curled leaves or hairs Thick waxy cuticle Thick fleshy stem that stores water Fewer stomata that only open at night Stomata sunken in pits
