transport in plants, water uptake & transpiration

The functions of xylem is/are

• to transport of water and mineral salts.

• to translocate organic nutrients.

• to provide support to the plant part by the rigidity of cell wall.

• to provide metabolic energy.

Phloem is responsible

• for downward translocation of organic nutrients to root cell.

• for upward translocation of minerals to stem tip.

• for providing support to the plant part.

• for providing water to the neighbouring cells.

A leafy shoot was placed in a beaker containing a blue dye and then examined 5 hours later.

Which statement explains the change in appearance?

• Blue dye stains cells in the leaves.

• Blue dye moves through the xylem.

• Blue dye moves up the stem by osmosis

• Blue dye diffuses through the cells of the plant.

Tags

NGSS.MS-LS2-3

The table shows the rates of water absorption and transpiration of a plant during one morning.

At what time does the plant show signs of wilting?

• 9 am

• 10 am

• 11 am

• 12 am

Xylem vessel elements are strengthened by

• lignin
• cellulose
• melanin
• pericycle

What controls the opening and closing of stomata?

• Chloroplasts

• Mitochondria

• Guard cells

Define "transpiration".

• The evaporation of water vapour from the leaves through the stomata.

• The transport of sugars from leaves to other parts of the plant.

• Where glucose is broken down with oxygen to transfer energy - occurs in the mitochondria.

What is the correct description of the transpiration stream.

• Water moves into roots by active transport, moves up the phloem to the leaves where some evaporates through the stomata - this creates a suction to pulls up more water behind it.

• Water moves into roots by osmosis, moves up the xylem to the leaves where some evaporates through the stomata - this creates a suction to pulls up more water behind it.

• Water moves into roots by diffusion, moves up the xylem to the leaves where some evaporates through the guard cells - this creates a suction to pulls up more water behind it.

Increasing the rate of photosynthesis will.............the rate of transpiration. What is the missing word/s?

• increase

• decrease

• not affect

How does temperature affect the rate of transpiration?

• As temperature increases the rate of transpiration decreases

• As temperature increases the rate of transpiration increases.

• As temperature increases the rate of transpiration stays constant