Plant tissues

What is the purpose of the xylem?

To transport minerals and water from the roots to the stem and leaves.

What is the structure of the xylem like?

It’s made up of dead cells that make hollow tubes strengthened by lignin.

What is the purpose of the phloem?

To transport food materials (sucrose and amino acids) made in the photosynthesising areas to the non-photosynthesising areas.

What is the structure of the phloem like?

It’s made up of a series of sieve plates and living cells.

Where is the xylem in a cross-section?

On the inside

Where is the phloem in a cross-section?

On the outside

What is the purpose of the waxy cuticle?

It’s a protective layer on top of a leaf that prevents water evaporating

What is the purpose of the upper epidermis?

It’s thin to allow light to enter the palisade mesophyll layer.

What is the purpose of the palisade mesophyll layer?

It’s a series of column shaped cells full of chloroplasts to absorb maximum light.

What is the purpose of the spongy mesophyll layer?

It contains air spaces that increase the surface area to volume layer.

What is the purpose of the lower epidermis?

It contains guard cells and stomata which control what enters and exixts.

What is the purpose of guard cells?

They absorb and lose water to open and close the stomata to allow gas diffusion.

What is the purpose of the stomata?

It’s where gas exchange and evaporation takes place.

What is the purpose of the vascular bundle?

It contains the xylem and the phloem to transport substances around the leaf.

How is larger surface area and adaptation?

It increases surface area for the diffusion of carbon dioxide and absorption of light.

How is a leaf being thin an adaptation?

It allows carbon dioxide to diffuse quicker.

How is chlorophyll an adaptation?

It absorbs light energy for photosynthesis.

How is a network of veins an adaptation?

It allows the transport of water to the cells of the leaf and carbohydrates from the leaf for photosynthesis.

Does the phloem or the xylem use transpiration?

Xylem

What is the direction of movement in the xylem?

Roots to leaves, only one way

Does the phloem or the xylem use translocation?

Phloem

What is the direction of movement in the phloem?

Any direction

Are the cells in the phloem dead or living?

Living

Are the cells in the xylem dead or living?

Dead