2. roots

Question 1

function of the root

Answer 1

anchorage
storage
nutrient/water absorption
transport
soil interaction

Question 2

difference between taproot and fibrous root

Answer 2

taproot- single, deep-growing root that provides strong anchorage and stores nutrients
fibrous root- many thin roots that spread out near the soil surface and are efficient in water and nutrient absorption

Question 3

what is an adventitious root

Answer 3

roots that develop from unusual locations on a plant, rather than from the primary root system. They can arise from stems, leaves, or other parts of the plant, and allows plants to enhance their stability, nutrient uptake, and reproductive capabilities

Question 4

types of adventitious roots

Answer 4

aerial
prop
climbing

Question 5

what are mycorrhizae

Answer 5

symbiotic associations between fungi and the roots of most plants. mycorrhizae form a crucial relationship with plants, enhancing their growth and survival in various environments

Question 6

function of mycorrhizae

Answer 6

-Nutrient absorption
-Water uptake
-Soil structure improvement
-Disease resistance
-Growth promotion
-Carbon sequencing

Question 7

what is glomalin

Answer 7

Glomalin is secreted by the hyphae of mycorrhizal fungi as they colonize plant roots and interact with the surrounding soil.
It is a complex glycoprotein, meaning it contains both carbohydrate and protein components. Its sticky nature allows it to bind soil particles together.

Question 8

root cap

Answer 8

protects the delicate apical meristem at the tip of the root as it pushes through the soil. It secretes mucilage, which lubricates the root’s passage through the soil, reducing friction and aiding in penetration

Question 9

apical meristem

Answer 9

region of undifferentiated cells that are actively dividing. This region is responsible for the growth of the root in length.

Question 10

zone of maturation

Answer 10

cells begin to differentiate into specific types of root cells. This region is characterized by the development of root hairs, which increase the surface area for water and nutrient absorption

Question 11

zone of elongation

Answer 11

newly formed cells from the apical meristem undergo elongation. This elongation contributes significantly to the overall increase in root length. The cells expand, allowing the root to penetrate deeper into the soil

Question 12

root hairs

Answer 12

extensions of epidermal cells that emerge in the zone of maturation. They greatly increase the root’s surface area, enhancing the root’s ability to absorb water and nutrients from the soil

Question 13

cortex

Answer 13

lies beneath the epidermis and is composed mainly of parenchyma cells. It stores carbohydrates and facilitates the movement of water and nutrients from the soil toward the vascular tissue. The cortex also acts as a barrier to prevent pathogens from entering the vascular system

Question 14

endodermis

Answer 14

innermost layer of the cortex and acts as a selective barrier, regulating the flow of water and dissolved substances into the vascular system. It contains the Casparian strip, a waxy barrier that prevents passive movement of materials, ensuring that substances pass through the endodermal cells for regulation

Question 15

pericycle

Answer 15

layer of cells located just inside the endodermis. It is responsible for the initiation of lateral roots and can also contribute to secondary growth in some plants

Question 16

what is the Casparian strip and its function

Answer 16

• a specialized band of suberin (a waxy substance) found in the cell walls of the endodermis
  -waterproof, hydrophobic barrier that surrounds each endodermal cell.
  -regulating the uptake of water and nutrients
  -protecting against harmful substances
  -ensuring efficient nutrient transport within the plant

Question 17

where do lateral roots emerge from

Answer 17

Lateral roots emerge from the pericycle, which is a layer of tissue located just inside the endodermis of a plant root

Question 18

Modified roots – examples and what modified for

Answer 18

specialized roots that have adapted to perform functions beyond the typical roles of anchoring the plant and absorbing water and nutrients

Question 19

modified root- adventitious roots

Answer 19

-zea mays (corn)
-roots arise from non-root tissues (like stems) and provide additional support, stability, and access to moisture. In some plants, they can also help in vegetative reproduction.

Question 20

modified root- storage root

Answer 20

-daucus carota (carrot)
-store carbohydrates and nutrients, enabling the plant to survive during adverse conditions such as drought or winter

Question 21

modified root- pneumatophores

Answer 21

-mangroves
-specialized aerial roots that grow upward, allowing the plant to take in oxygen from the atmosphere in waterlogged environments.