Plants

Question 1

Why do plants need a specialised transport system

Answer 1

-Multicellular plants are large- low SA:V ratio- can’t rely on diffusion alone

-Due to their high metabolic rate, sugars must be transported to these tissues, and other molecules like minerals ions. And hormones.

Question 2

What do seeds contain

Answer 2

An embryonic leaf called a cotyledon, when a seed germinated the consulted on unfurls allowing the seedling to carry out photosynthesis. Some plants only have one cotyledon,like grass. Or two.

Question 3

Difference between plants with one cotyledon and two

Answer 3

One=monocotyledenous

Two=dicotyledenous

Question 4

What are trees an example of

Answer 4

Woody dicotyledonous plants- long lived and have a woody stem

Question 5

What are geraniums (flowers) an example of

Answer 5

herbaceous dicotyledonous plants- often fast growing and short-lived. Don’t have woody stem.

Question 6

Is the arrangement of vascular bundles different

Answer 6

Yes it is different in the roots the stem and the leaves.

Question 7

Where do root hair cells grow from

Answer 7

A layer of external tissue called the epidermis

Question 8

Structure of root

Answer 8

Outer epidermis- then thick layer of cortex(contain parenchyma cells)

• in the centre of the root we have vascular bundle- surrounded by layer of cells called the endodermis

-in the vascular bundle we have xylem vessels in centre with the phloem vessels around the xylem. Because they are grouped together in the centre of the root this helps to prevent the root from being pulled out the soil.

Question 9

Structure of stem

Answer 9

-Vascular bundles are arranged in rings around the edge of the stem.

-centre of plant stem is called the pith (consists of parenchyma cells)

• around edge we have epidermis and cortex.

-xylem vessels are found closer to the centre.

-because vascular bundles are around edge of stem this helps it to withstand bending due to wind.

Question 10

Cross-section of leaf

Answer 10

Vascular bundle in centre- midrib - provides support as well as transport.- the leaf is also supported by smaller vascular bundles connected to the main one.

-xylem is at upper part of bundle and phloem lower.

-photosynthesis mainly takes place in palisade mesophyll- in upper part of leaf.