Chapter 3: Nutrition in plants ( 3.2-3.3)

Question 1

What are the functions of the root?

Answer 1

• provide support and strength to anchor the plant

- absorb water and mineral salts

Question 2

What protects the root from being damaged when it continues to grow into the ground?

Answer 2

• root cap

Question 3

Each epidermal cell of root differentiates to form a tiny, tube-like projection called ________.

Answer 3

• root hair

Question 4

Explain root collar.

Answer 4

• part of a root connected to the base of the plant stem

Question 5

Explain endodermis.

Answer 5

• closely arranged and one cell thick

- most endodermal cells have suberin or lignin thickening

Question 6

________ is involved in secondary growth and lateral roots formation.

Answer 6

• pericycle

Question 7

Explain uptake of water by root hair cells.

Answer 7

• by osmosis
• soil water has a higher water potential
• diffuse into root hair cell
• diffuses through the cortex enters the xylem

Question 8

Explain uptake of mineral salts by root hair cells.

Answer 8

• by active transport
• energy required
• against concentration gradient from a lower concentration of mineral ions

Question 9

Relate root adaptations for water and mineral salts with root hairs.

Answer 9

• have a large number of root hair cells to provide a large surface area
• tiny to enable root hairs to penetrate between soil particles

Question 10

Relate root adaptations for water and mineral salts with cortex cells and xylem tissue.

Answer 10

• cortex cells have thin cell walls which facilitate water movement in the roots
• cortex cells are loosely arranged to facilitate gaseous exchange

Question 11

List other adaptations of root hair cells to absorb water from the soil.

Answer 11

• thin wall to speed up the intake of water by osmosis
• large vacuole to store water and increase water absorption
• vacuole has salts to speed up water absorption
• no cuticle as this would prevent water absorption

Question 12

Based on the nutritional adaptation, plants can be classified into three main types______, ______ and ______.

Answer 12

• carnivorous plants
• parasitic plants
• epiphytic plants

Question 13

Carnivorous plants are plants that ____________.

Answer 13

• trap and feed on insects and other animals to obtain nutrients

Question 14

Which both plant types can carry out photosynthesis?

Answer 14

• carnivorous

- epiphytic

Question 15

Can parasitic plants carry out photosynthesis?

Answer 15

• No except for some like mistletoe

Question 16

Tell one main difference between parasitic plants and epiphytic plants.

Answer 16

• parasitic plants obtain their nutrients from other plants and cause harm to host plants
• epiphytic plants are green plants that grow on another plant for physical support

Question 17

Give two examples of carnivorous plants, parasitic plants, and epiphytic plants.

Answer 17

• pitcher plant and venus flytrap ( carnivorous )
• Rafflesia and mistletoe ( parasitic )
• pigeon orchid and bird’s nest fern ( epiphytes )

Question 18

Explain epiphytes.

Answer 18

• usually grow at a higher position to obtain maximum sunlight
• obtain water trapped in the crevices on the bark
• carry out photosynthesis
• host plants are neither harmed nor benefits

Question 19

What is secreted in carnivorous plants?

Relate nitrogen to carnivorous plants.

Answer 19

• nectar
• trapped animals can supply nitrogen
• nitrogen is important for the growth
• because they live in soil which lacks nitrogen sources

Question 20

What is haustorium in parasitic plants?

Answer 20

• a specialized root-liked organ that penetrates the host and fuses with vascular tissue to obtain water

Question 21

Explain pitcher plants.

Answer 21

• uses pitfall traps

- has a hollow, lidded leaf filled with liquid to digest the prey