ESO 4 B & G 5

Plant Physiology

What to Learn

  • Plant nutrition: absorption and transport of nutrients, transpiration, photosynthesis, respiration.
  • Plant reproduction: the flower, pollination, fertilization, seed dispersal, germination.
  • Plant interaction: plant hormones and growth.

Key Information

Mind Map: Events after fertilisation
[Source]

Movies, Animations and Audios

Plant Nutrition
Zoom into a leaf

Zoom into a leaf

Watch the surface and the inside of a leaf progressively magnified by an electron microscope.

Photosynthesis

Photosynthesis

Learn how photosynthesis is performed inside the chloroplasts.

Produced by Britannica.com

Respiration

Respiration

Learn if and when a plant respires, absorbing CO2 and producing O2.

Produced by Britannica.com

Plant Reproduction
Plant fertilization

Plant fertilization

Learn how male and female gametes fuse in plants and what happens afterwards.

Produced by Britannica.com

Double fertilization in flowering plants

Double fertilization in flowering plants

Detailed view of the process of fertilization in plants.

Reproduction of the pine tree

Reproduction of the pine tree

Learn the specificities of the reproduction process in the gymnosperms.

Produced by Britannica.com

Plant Interaction and Growth
Plant hormones and growth

Plant hormones and growth

Learn how plant hormones control their growth towards the light.

Produced by Britannica.com

Leaves maintain a constant temperature

Leaves maintain a constant temperature

A 60-second Science podcast.

Streamed from Scientific American

Images

Activities

Questions: Plant Nutrition
[Source lesson]
  1. What features of the leaves make them ideal for photosynthesis?
  2. Why are leaves green?
  3. Which is the leave tissue with the lowest amount of chloroplasts?
  4. Why does the palisade mesophyll contain a greater amount of chloroplasts than the spongy mesophyll?
  5. What is the waxy cuticle that covers the leaves meant for?
  6. Why do holm oaks contain a thicker waxy cuticle than the deciduous oaks?
  7. Describe the structure of a vascular bundle and the function of each of its tissues.
  8. Write the formula of photosynthesis.
  9. Why should you place a plant in the dark prior to a starch test?
  10. Why should you choose a leaf from a variegated plant in a starch test?
  11. Why should you cover a part of the leaf with a piece of foil during a starch test?
  12. What do you demonstrate by putting a leave inside a flask containing KOH during a starch test? Why?
  13. Draw a diagram showing the uses a plant may give to glucose.
  14. Which is the functionally equivalent polysaccharide to starch in animals? Why?
  15. What is a limiting factor? Give an example.
  16. How can you test for the effect of (only) light in photosynthesis?
  17. Why does not the rate of photosynthesis increase indefinitely with the light intensity?
  18. What does the action of an enzyme depend on? Why an increase of temperature above the optimum will decrease the rate of photosynthesis? How do you call the process that takes place under those conditions?
  19. When in a day is the compensation point between CO2 released by respiration and CO2 absorbed by photosynthesis reached? Why?
Questions: Plant Transpiration
[Source lesson]
  1. Which are the two physical processes that allow the loss of water in the leaves?
  2. "If a plant wants to obtain water, it has to lose water". Is this assertion true? Why?
  3. Why is it good for a plant to lose water by transpiration?
  4. Why is it bad for a plant to lose water by transpiration?
  5. Why is transpiration important to keep a plant upright?
  6. How does transpiration make the replication of DNA possible?
  7. Where is the boundary layer thicker: around the leaves of a cactus or around the leaves of a poplar? Why?
  8. How does the rate of transpiration change when you take a plant from inside a house to a garden? Why?
  9. How does the rate of transpiration change when you start boiling water in the same room where you have a plant? Why?
Questions: Plant Transport
[Source lesson]
  1. What main kinds of things can you find in a soil?
  2. What are the main functions of water in a plant?
  3. What is the main adaptation of a plant to increase the absorption of water?
  4. What does each root hair consist of? Which is the main organelle in them?
  5. Why and how is the water absorbed into the root hairs?
  6. Why and how does the water pass from the root hairs to the inside of the root?
  7. What tissue transports the water up the plant?
  8. Why and how do the soil's minerals pass to the inside of the roots?
  9. Under what conditions is a plant likely to release minerals to the soil? Why doesn't this happen? What is the main requirement to prevent loss of minerals from the roots?
  10. What are the main uses of sugar in a plant?
  11. What are the main chemical elements that a plant must take from the soil? Which are the main mineral ions that provide them?
  12. What are the main uses of nitrogen in a plant? What are the main symptoms of its deficiency?
  13. What are the main uses of phosphorus in a plant? What are the main symptoms of its deficiency?
  14. What are the main uses of potassium in a plant? What are the main symptoms of its deficiency?
  15. What are the main uses of magnesium in a plant? What are the main symptoms of its deficiency?
  16. What kind of experiment can you perform to test the effects of the absence of a mineral?
  17. What is xylem meant for? What does it consist of? Where is it located in a plant?
  18. What is phloem meant for? What does it consist of? Where is it located in a plant?
  19. What happens when a peripheral ring of tissue is removed from the stem of a plant? Why?
  20. How is it possible the transport of water up the plant through the xylem?
  21. What is the structure of the xylem vessels? What special chemical do they contain? What are the functions of this chemical?
  22. What can you find in a leaf vein?
  23. What is the role of the water in holding a plant upright?
  24. What environmental conditions favour the transpiration of water? Why?
  25. Why is transpiration faster during daytime?
  26. Draw the cross-section of a leaf, labelling its structures and tissues.
  27. Why do leaves need to be covered by a waxy cuticle?
  28. What is the structure of a stoma? Why and under what conditions are stomata open? And closed?
  29. What is a potometer meant for? How does it work?
  30. Name some adaptations of dry environment plants to reduce water loss.
Questions: Plant Reproduction
  1. There are two ways in which a plant can be hermaphrodite. Which ones?
  2. What is the minimum composition of a male flower?
  3. The anthers of grasses are very big and dangle out of the flower. Do you expect these flowers to have a colourful big corolla? Why?
  4. Which one of the three main parts of a pistil is the least necessary? Why?
  5. How many nuclei does each pollen grain have when it is fully developed?
  6. What is the mission of the tube nucleus of a pollen grain?
  7. There is one egg-cell inside each _______________. One ovary can contain one or several _______________.
  8. When fertilized, the ovules develop into _______________ and the ovaries that contain them develop into _______________.
  9. What is the micropyle?
  10. Why is plant fertilization called "double fertilization"?
  11. What are the main components of a seed? What is the function of each?
  12. How can a fleshy fruit help the dispersal of its seeds?