Grade 9 Science — Reproduction: how life continues

Tell asexual reproduction from sexual, name the parts of a flower and follow pollen through to a seed, and describe fertilization and the reproductive cycle in animals and humans.

Name: ________________________

Before you start

The parts of a flower, each one named.

1. The green flap at the base — a sepal
2. The broad flap sweeping out to the side — a petal
3. The small sac on the end of the slender stalk — the anther of a stamen
4. The flattened cap on top of the central column — the stigma
5. The thin central column — the style
6. The rounded swelling at the base of the column — the ovary

Sepals and petals are the two outer whorls. The stamen is the male part and the pistil — stigma, style and ovary together — is the female one.

1.A frog lays thousands of eggs in a pond while a bird lays a handful in a nest. What does the chapter say about the two strategies?
- a) The frog's fertilization is internal and the bird's external
- b) Both fertilize internally, and the difference lies in nest-building
- c) Survival is the same in both; the frog simply lays more
- d) The frog's fertilization is external and survival is low; the bird's is internal and survival is better
2.Tap the part of this flower that produces the pollen grains.
Write the number of the part.
3.A gardener grows twenty plants from cuttings of one rose bush. How do the new plants compare with the parent?
- a) They vary from it, because cuttings mix genetic material from two parents
- b) They are genetically identical to it, because one parent and mitosis were involved
- c) They vary, because meiosis takes place when a cutting roots
- d) They are identical to each other but different from the parent
4.Sort each case by the kind of reproduction it is.
Groups: Asexual reproduction · Sexual reproduction
- A male gamete from a pollen grain fusing with an egg cell
- A gardener rooting a sugarcane stem cutting
- A frog releasing eggs into water for a male to fertilize
- A Bryophyllum leaf sprouting tiny plantlets
- A potato sprouting new plants from its underground stem
5.What is the one-word name for the transfer of pollen grains from a stamen to a stigma?
6.In a butterfly's development, which stage is described as the feeding stage that gathers the nutrition the adult body is built from?
- a) The adult
- b) The larva
- c) The egg
- d) The pupa
7.A flower is fertilized. What becomes of the ovary?
- a) It falls away once the seeds are formed
- b) It enlarges and develops into the fruit
- c) It grows into the pollen tube
- d) It becomes the seed, while the ovules become the fruit
8.Match each part of a flower to what it does.
- Anther
- Stigma
- Style
- Ovary
- Sepal
- Connects the stigma down to the ovary
- Holds the ovules and becomes the fruit
- Receives the pollen
- Produces the pollen grains
- Protects the flower while it is in bud

Answer key — Grade 9 Science — Reproduction: how life continues

1. d) The frog's fertilization is external and survival is low; the bird's is internal and survival is better
2. 3 — The small sac on the end of the slender stalk
3. b) They are genetically identical to it, because one parent and mitosis were involved
4. A potato sprouting new plants from its underground stem → Asexual reproduction; A Bryophyllum leaf sprouting tiny plantlets → Asexual reproduction; A gardener rooting a sugarcane stem cutting → Asexual reproduction; A male gamete from a pollen grain fusing with an egg cell → Sexual reproduction; A frog releasing eggs into water for a male to fertilize → Sexual reproduction
5. pollination
6. b) The larva
7. b) It enlarges and develops into the fruit
8. Anther → Produces the pollen grains; Stigma → Receives the pollen; Style → Connects the stigma down to the ovary; Ovary → Holds the ovules and becomes the fruit; Sepal → Protects the flower while it is in bud