Grade 9 : Science - 3. Reproduction (Set 1) | Concept of Maths

Question 1

Yeast reproduces asexually by budding. If a single parent yeast cell with chromosome number 2n undergoes budding, what is the ploidy/chromosome number of the resulting offspring cell (bud)?

Accepted Answer

B) 2n

Answer

A) n

Answer

C) 3n

Answer

D) 4n

Question 2

Binary fission in Amoeba results in the division of a single parent cell into 2 identical daughter cells. If a single Amoeba cell undergoes 3 successive binary fissions, how many daughter cells are produced in total?

Accepted Answer

C) 8

Answer

A) 4

Answer

B) 6

Answer

D) 16

Question 3

In flowering plants, the stamen is the male reproductive part and produces pollen grains, which are haploid (n). If the pollen grains of a plant contain n = 12 chromosomes, what is the diploid chromosome number (2n) of the plant's vegetative leaf cells?

Accepted Answer

C) 24

Answer

A) 6

Answer

B) 12

Answer

D) 36

Question 4

Rhizopus (bread mould) reproduces asexually by forming spores inside a structure called the sporangium. Since the parent hyphae are haploid (n), the asexual spores produced within the sporangium are:

Accepted Answer

A) Haploid (n)

Answer

B) Diploid (2n)

Answer

C) Triploid (3n)

Answer

D) Tetraploid (4n)

Question 5

During sexual reproduction, a male gamete (n) fuses with a female gamete (n) in a process called fertilization. What is the ploidy level of the resulting zygote?

Accepted Answer

B) Diploid (2n)

Answer

A) Haploid (n)

Answer

C) Triploid (3n)

Answer

D) Polyploid

Question 6

Bryophyllum can reproduce vegetatively through buds formed in the notches of its leaves. If a single Bryophyllum leaf contains 5 active notches, and each notch grows into exactly 1 individual plantlet, how many new plantlets are formed?

Accepted Answer

B) 5

Answer

A) 1

Answer

C) 10

Answer

D) 15

Question 7

In a sexually reproducing animal, if a sperm cell contains x chromosomes and an egg cell contains x chromosomes, how many chromosomes are present in the zygote formed after fertilization?

Accepted Answer

C) 2x

Answer

A) x

Answer

B) $\frac{x}{2}$

Answer

D) $x^2$

Question 8

Spirogyra, a multicellular filamentous alga, reproduces by breaking down its body filament into multiple smaller pieces, each of which matures into a new individual. This method of reproduction is classified as:

Accepted Answer

D) Asexual reproduction

Answer

A) Sexual reproduction

Answer

B) Budding

Answer

C) Spore formation

Question 9

Self-pollination is defined as the transfer of pollen grains from the anther to the stigma of the same flower or another flower on the same plant. If P represents the probability of self-pollination occurring in a strictly self-pollinating species under isolated conditions, then:

Accepted Answer

C) P = 1

Answer

A) P = 0

Answer

B) P = 0.5

Answer

D) P > 1

Question 10

After fertilization in a flowering plant, ovules mature into seeds while the ovary develops into a fruit. If an ovary contains 8 ovules, what is the maximum possible number of seeds that can be formed?

Accepted Answer

C) 8

Answer

A) 2

Answer

B) 4

Answer

D) 16