biology MCQs - 9th class Chapter 09 Mcqs

1

Which of these is a major component of all biomolecules?

A

Iron

B

Carbon

C

Zinc

D

Nickel

2

The process of water loss from the plant surface in the form of vapours is called?

A

Guttation

B

Respiration

C

Transpiration

D

Osmosis

3

Which mineral is a component of chlorophyll and activates many enzymes?

A

Nitrogen

B

Phosphorus

C

Magnesium

D

Potassium

4

The transport of water and salts in most land plants is carried out by?

A

Phloem

B

Xylem

C

Cortex

D

Epidermis

5

The movement of ions from a region of lower concentration to higher concentration using energy is known as?

A

Passive Transport

B

Osmosis

C

Diffusion

D

Active Transport

6

Tiny hair-like extensions of the epidermis in roots are called?

A

Lenticels

B

Stomata

C

Root hairs

D

Vascular bundles

7

Most of the transpiration in plants occurs through?

A

Lenticels

B

Cuticle

C

Stomata

D

Bark

8

What causes guard cells to become turgid and open the stoma during the day?

A

Influx of sodium ions

B

Influx of potassium ions

C

Efflux of potassium ions

D

Efflux of glucose

9

Which factor decreases the rate of transpiration?

A

High temperature

B

High wind speed

C

High humidity

D

Large leaf surface area

10

The pulling force created by transpiration is known as?

A

Root pressure

B

Osmotic pull

C

Transpirational pull

D

Cohesion force

11

In most plants, food is transported in the form of?

A

Glucose

B

Starch

C

Fructose

D

Sucrose

12

According to the pressure flow mechanism, food flows from a?

A

Sink to a source

B

Source to a sink

C

Root to a leaf

D

Xylem to a phloem

13

During the daytime, which process releases oxygen in plants?

A

Respiration

B

Photosynthesis

C

Transpiration

D

Guttation

14

In woody stems, gaseous exchange occurs through special pores called?

A

Stomata

B

Hydathodes

C

Lenticels

D

Cuticles

15

The release of water droplets from the tips of leaves at night is called?

A

Transpiration

B

Dew formation

C

Guttation

D

Excretion

16

Plants that live in extremely dry environments are known as?

A

Hydrophytes

B

Mesophytes

C

Halophytes

D

Xerophytes

17

Which mineral is necessary for photosynthesis and activates many enzymes?

A

Boron

B

Iron

C

Molybdenum

D

Chlorine

18

A deficiency in which element causes chlorosis, the yellowing of leaves?

A

Potassium

B

Calcium

C

Nitrogen

D

Sulphur

19

The innermost boundary of the cortex in a root is the?

A

Epidermis

B

Pericycle

C

Endodermis

D

Xylem

20

Water molecules sticking to the walls of xylem vessels is an example of?

A

Cohesion

B

Adhesion

C

Tension

D

Transpiration

21

Photosynthetic tissues like the mesophyll of leaves are considered a?

A

Sink

B

Source

C

Transport channel

D

Waste site

22

Plants that live in salty water habitats are called?

A

Xyrophytes

B

Mesophytes

C

Halophytes

D

Hydrophytes

23

The primary function of root hairs is to?

A

Store food

B

Provide support

C

Increase surface area for absorption

D

Synthesize proteins

24

What is the role of companion cells in the phloem?

A

Provide structural support

B

Store sucrose

C

Provide energy for active transport

D

Transport water

25

Which of these is considered a micronutrient for plants?

A

Carbon

B

Oxygen

C

Copper

D

Magnesium

26

What happens to stomata during the evening?

A

They open due to high glucose

B

They close as potassium ions move out

C

They remain open for respiration

D

They close due to water influx

27

Water moves from the soil into root hairs primarily by?

A

Active transport

B

Osmosis

C

Bulk flow

D

Filtration

28

The two-way passage for food in a plant is the?

A

Xylem

B

Cortex

C

Epidermis

D

Phloem

29

Which plants have broad leaves with a large number of stomata on their upper surfaces?

A

Xerophytes

B

Hydrophytes

C

Mesophytes

D

Halophytes

30

Rubber plants excrete metabolic waste in the form of?

A

Resins

B

Gums

C

Latexes

D

Mucilage

31

Which mineral is a component of ATP and nucleic acids?

A

Nitrogen

B

Sulphur

C

Phosphorus

D

Potassium

32

The movement of water molecules through a semi-permeable membrane is?

A

Diffusion

B

Active transport

C

Osmosis

D

Hydrolysis

33

The loss of water through the cuticle on the leaf epidermis is called?

A

Stomatal transpiration

B

Lenticular transpiration

C

Guttation

D

Cuticular transpiration

34

What is the function of the pericycle?

A

Water storage

B

Forms a protective layer

C

Gives rise to lateral roots and is where water moves into xylem

D

Photosynthesis

35

An increase in temperature generally leads to?

A

A decrease in transpiration

B

An increase in transpiration

C

No change in transpiration

D

An increase in guttation

36

Growing tips of roots and stems are examples of a?

A

Source

B

Sink

C

Reservoir

D

Conduit

37

During the night, plants primarily take in which gas from the environment?

A

Carbon dioxide

B

Oxygen

C

Nitrogen

D

Water vapour

38

Plants like cacti store water in soft, juicy stems called?

A

Tubers

B

Succulent organs

C

Bulbs

D

Rhizomes

39

Which mineral helps in sugar transport and cell division?

A

Iron

B

Manganese

C

Boron

D

Zinc

40

What causes the continuous water column in the xylem to be pulled upwards?

A

Root pressure

B

Gravity

C

Tension from transpiration

D

Active transport in leaves

41

Which of the following is an example of a mesophyte?

A

Cactus

B

Water lily

C

Maize

D

Sea grass

42

A structural component of cell walls that also activates enzymes is?

A

Sulphur

B

Potassium

C

Magnesium

D

Calcium

43

The function of phloem is the translocation of?

A

Water

B

Minerals

C

Food

D

Hormones

44

Which tissue is located just inside the endodermis?

A

Cortex

B

Epidermis

C

Pericycle

D

Phloem

45

The higher the humidity, the ______ the rate of transpiration.

A

lower

B

higher

C

faster

D

unaffected

46

Which ion's active transport into guard cells is the first step in stomatal opening?

A

Sodium (Na+)

B

Calcium (Ca2+)

C

Potassium (K+)

D

Magnesium (Mg2+)

47

Nitrogen is absorbed by plant roots mainly in the form of?

A

Ammonia

B

Nitrites

C

Nitrogen gas

D

Nitrates

48

Acacia (keekar) tree excretes its waste products as?

A

Latex

B

Resins

C

Gums

D

Mucilage

49

Which of these is NOT a method for excreting metabolic wastes in plants?

A

Storing in leaves that fall

B

Exhaling through lungs

C

Release as gums or resins

D

Guttation

50

The narrow diameter of xylem vessels contributes to which force?

A

Cohesion

B

Adhesion

C

Both cohesion and adhesion

D

Transpirational pull