[Bi] - Topic 7 Flashcards
What is photosynthesis?
Photosynthesis is the process by which use sunlight to synthesize foods with the help of chlorophyll.
Write the word equation for photosynthesis.
Carbon dioxide + Water → Glucose + Oxygen
Write the balanced chemical equation for photosynthesis.
6 CO₂ + 6 H₂O → C₆H₁₂O₆ + 6 O₂
Where in the plant cell does photosynthesis take place?
Photosynthesis takes place in the chloroplasts of plant cells.
What is the function of the stomata in leaves?
Stomata are pores on the leaf surface that allow gas exchange; they let carbon dioxide in and oxygen out.
How do guard cells function in the opening and closing of stomata?
Guard cells control the opening and closing of stomata by changing shape due to the uptake or loss of water.
What is transpiration?
Transpiration is the process of water movement through a plant and its evaporation from aerial parts, especially from the leaves.
What is the equation for the rate of transpiration?
Rate of transpiration = Volume of water lost / Time
What is the role of xylem in plants?
Xylem transports water and minerals (dissolved potassium, nitrates etc) from the roots to the rest of the plant.
Describe the structure of xylem.
Xylem vessels are long, tube-like structures formed from dead cells. They have no organelles present (because cells are dead), there’s no barrier between cells and they’re surrounded by lignin which is hard and a water barrier (water cannot escape).
What is the role of phloem in plants?
Phloem transports dissolved sugars - called Translocation
Describe the structure of phloem.
Phloem consists of living cells arranged end to end, forming sieve tubes. Phloem also have companion cells at the sides that keep them alive. Direction of travel is 2 way (up and down the plant).
What is phototropism?
Phototropism is the growth of a plant in response to light direction.
What hormone is primarily involved in phototropism?
Auxin.
Define “tropism.”
Tropism is the growth response of a plant toward or away from a stimulus.
What is geotropism (or gravitropism)?
Geotropism is the growth of a plant in response to gravity.
What is the role of gibberellins in plant growth?
Gibberellins promote seed germination, stem elongation, and flowering.
What is the function of the cuticle on a leaf?
The cuticle is a waxy layer that reduces water loss from the surface of the leaf.
What are meristems?
Meristems are regions of undifferentiated cells in plants where active cell division occurs, allowing for growth.
What are the different types of meristem and where are they found?
Shoot (found at the tip of the shoots), root (found at the tip of the roots) and lateral (found at the side of branches).
What is the role of roots in a plant?
Roots anchor the plant, absorb water and minerals from the soil, and sometimes store food.
What is greenhouse economics?
Greenhouse economics involves optimizing the conditions inside a greenhouse to maximize plant growth and yield, balancing factors like light, temperature, and carbon dioxide levels against costs to achieve profitable crop production.
How do plants use glucose produced in photosynthesis? (Hint: 5 things)
Respiration
Make cellulose
Store as starch
Make amino acids
Make lipids
What are the limiting factors of photosynthesis?
The limiting factors of photosynthesis are light intensity, carbon dioxide concentration, temperature and water.
