AmbifulWorksheets
Practice that never repeats
CBSE · Class 9 · Science

Reproduction: How Life Continues

Standard difficulty · 20 questions · 40 marks

Name: Date: Score: ____ / 40

Show your working for Sections B and C. Answers are on the last page — try every question first!

Section A — Choose the correct answer8 × 1 = 8 marks
1.
Asexual reproduction in bacteria is by:
  1. binary fission
  2. budding
  3. vegetative propagation (rhizomes)
  4. vegetative propagation (leaf buds)
2.
Which part of a flower holds the anther up?
  1. The pollen tube
  2. The sepal
  3. The filament
  4. The ovule
3.
Reproduction that needs only one parent is called:
  1. pollination
  2. sexual reproduction
  3. fertilisation
  4. asexual reproduction
4.
A body cell of a frog has 26 chromosomes. How many chromosomes are there in an egg cell?
  1. 52
  2. 26
  3. 13
  4. 15
5.
A bacterium splits by binary fission every 30 minutes. Starting with 11 cells, how many cells are there after 150 minutes?
  1. 352
  2. 21
  3. 110
  4. 704
6.
The embryo develops in:
  1. the oviduct (fallopian tube)
  2. the vas deferens
  3. the uterus
  4. the testes
7.
45 of 60 seeds germinated. The germination rate is:
  1. 75%
  2. 80%
  3. 25%
  4. 45%
8.
Assertion (A): Offspring of Amoeba are almost identical to the parent.
Reason (R): Amoeba makes gametes that fuse.
  1. Both A and R are true, and R is the correct explanation of A.
  2. Both A and R are true, but R is not the correct explanation of A.
  3. A is true, but R is false.
  4. A is false, but R is true.
Section B — Short answer8 × 2 = 16 marks
9.
Name the method of asexual reproduction in Bryophyllum, and describe it in one line.
10.
Give two differences between regeneration and fragmentation.
11.
Why is reproduction essential for a species, though not for an individual?
12.
A brinjal has 83 seeds. How many ovules were fertilised, and at least how many pollen grains must have grown pollen tubes?
13.
A body cell of rice has 24 chromosomes. How many are there in its gametes, and in the zygote?
14.
Name the part of a flower that (a) holds the anther up, and the part that (b) carries the male gamete down to the ovule.
15.
One Plasmodium cell splits into 9 daughter cells by multiple fission. If each of them does the same once more, how many cells are there?
16.
A bacterium divides by binary fission every 45 minutes. Starting with 7 cells, after how many minutes will there be 3,584 cells?
Section C — Word problems4 × 4 = 16 marks
17.
Describe the steps from pollination to the formation of a seed and a fruit.
18.
A gardener wants 175 mango plants exactly like one good parent plant. Which method should be used, and which part of the plant? Give two advantages. If 20% of the pieces planted fail to grow, at least how many pieces must be planted?
19.
Two trays each have 50 seeds. Tray A is watered and kept warm; tray B is kept under water with no air. After a week 38 seeds in A and 6 in B have germinated. Find the germination rate of each tray and say what the experiment shows.
20.
Explain: (a) The embryo in the uterus can grow for nine months. (b) Some flowers are brightly coloured and scented.
AmbifulWorksheets
Practice that never repeats
CBSE · Class 9 · Science

Answer key

Reproduction: How Life Continues · AW-9S-REP-2026-V1 · For parents — fold back or tear off before handing the sheet to your child.

QAnswerWorking
1(a) binary fission—
2(c) The filament—
3(d) asexual reproduction—
4(c) 13gametes have half: 26 ÷ 2
5(a) 3525 divisions: 11 × 25
6(c) the uterus—
7(a) 75%45 ÷ 60 × 100
8(c) A is true, but R is false.A is true: yes: Amoeba reproduces by binary fission. R is false.
9Vegetative propagation (leaf buds)—
10In regeneration a body part or a piece grows into a whole organism using specialised cells (Planaria); in fragmentation a simple body just breaks up and each piece grows (Spirogyra).—
11An individual can live without reproducing, but a species would die out without new members to replace those that die.—
1283; 83each seed comes from one fertilised ovule, and each ovule is reached by its own pollen tube
1312; 24gamete: 24 ÷ 2; zygote: 12 + 12
14(a) the filament, (b) the pollen tube—
15819 × 9
16405 minutes3,584 ÷ 7 = 512 = 2 multiplied 9 times, so 9 divisions × 45 minutes
17Pollen lands on the stigma (pollination) and grows a pollen tube down the style into the ovary. The tube carries the male gamete to an ovule, where it fuses with the female gamete (fertilisation) to form a zygote. The zygote becomes the embryo, the ovule becomes the seed and the ovary becomes the fruit.—
18Vegetative propagation, using grafting. The new plants are identical to the parent and grow and fruit sooner than plants raised from seed. At least 219 pieces.80% of the pieces must give 175: 175 ÷ 0.8 = 218.75, round up
19A: 76%, B: 12%. Seeds need air (oxygen) to germinate.38 ÷ 50 × 100; 6 ÷ 50 × 100
20(a) The placenta passes food and oxygen from the mother’s blood to the embryo. (It is joined to the mother by the placenta.) (b) Insects carry pollen from flower to flower (cross-pollination). (Colour and scent attract insects.)—