Reproduction in Organisms

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Questions:

Multiple Choice Question

10 x 1 = 10

Which one of the following is common to multicellular fungi, filaments algea and protonema of mosses?

(a)

Diplontic life cycle

(b)

Members of kingdom plantae

(c)

Mode of Nutrition

(d)

Multiplication by fragmentation

Which one of the following processes results in the formation of clone of bacteria?

(a)

Transformation

(b)

Transduction

(c)

Binary Fission

(d)

Conjugation

Which of the following is a post-fertilisation event in flowering plants?

(a)

Transfer of pollen grains

(b)

Embryo development

(c)

Formation of flower

(d)

Formation of pollen grains

There are various types of reproduction. The type of reproduction adopted by an organism depends on:

(a)

The habitat and morphology of the organism

(b)

Morphology of the organism

(c)

Morphology and physiology of the organism

(d)

The organism's habitat, physiology and genetic makeup

Offsprings formed by sexual reproduction exhibit more variation than those formed by asexual reproduction because:

(a)

Sexual reproduction is a lengthy process

(b)

Gametes of parents have qualitatively different genetic composition

(c)

Genetic material comes from parents of two different species

(d)

Greater amount of DNA is involved in sexual reproduction.

vegitative propagation in mint occurs by

(a)

Offset

(b)

Rhizome

(c)

Sucker

(d)

Runner

Study of pollen grain is called

(a)

Ethmology

(b)

Palynology

(c)

Paleobotany

(d)

Co-taxonomy

Spermatids are transformed into spermatozoa by

(a)

Spermiation

(b)

Spermatogenesis

(c)

Meiosis

(d)

Spermatosis

(e)

Spermiogenesis

Which of the following statements true of date plam?

(a)

It is monoecious producing both staminate flowers and pistilate flowers in the same plant.

(b)

It is monoecious producing staminate flowers in one tree and pistillate flowers in another tree.

(c)

It is dioecious producing staminate flowers in one tree and pistillate flowers in another tree.

10.

Which of the following statement is true of Hydra?

(a)

It produces asexual gemmules

(b)

It produces unicellular bud

(c)

It produces multicellular bud.

1 Marks

5 x 1 = 5

11.

Name the phase all organism have to pass through before they can reproduce sexually

12.

Select the organism which reproduces by binary fission: Amoeba, Hydra, Penicillium, Paramecium, Paramecium, Sponge.

13.

What is clone?

14.

Name the carrier of male gametes in seed-plants.

15.

Why are male gametes produced in thousands, while female gametes are few?

Generic 2

5 x 2 = 10

16.

List different ways of asexual reproduction.

17.

Why offsprings of oviparous animals are at greater risk for survival?

18.

A haploid organism produces gametes by mitosis. Does it mean that meiosis never occurs in such organisms? Justify your answer.

19.

A list of three flowering plants is given below. Which ones out of them are
(i) monoecious and
(ii) bearing pistillate flowers? Date palm, Cucurbits and Pea.

20.

The cell division involved in gamete formation is not of the same type in different organisms. Justify.

Generic 3

5 x 3 = 15

21.

Gametes are never formed by meiosis in haploid individuals. Is meiosis absent or present in haploid organisms? If present then when does it occur?

22.

Differentiate between oviparous and viviparous animals with an example of each.

23.

Differentiate between external fertilisation and internal fertilisation with an example for each.

24.

Describe the process of sporulation seen in Amoeba.

25.

How does yeast reproduce asexually? Show it diagrammatically.

Generic 5

2 x 5 = 10

26.

Jagan has two mango trees in the backyard of his house, which yielded fruits for the first time during this summer. The fruits were small, fibrous and not so sweet. In the next house, where his friend Ajay livers, there is a mango tree, which yields fruits that are fleshy/juicy, very sweet and bigger in size. Ajay, a student of B.sc. (Botany) comes out with an idea and takes some branches from the jagan's garden to his garden and explains the procedure.
(a) What method do you think Ajay has suggested for getting good quality fruits, on the trees of Jagan's house in a short period of time, i.e. during the next season?
(b) Describe how it is carried out to help japan.
(c) What are its advantages over growing a mango tree with the seeds obtained from Ajay's garden?
(d) Mention the values expressed by Ajay in this case.

27.

(a) Name two animals showing external fertilisation. Why are move gametes produced by such animals?
(b) Name two animals showing internal fertilisation. What are the characteristics of the gametes produced by such aimals?

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Answers Key:

Multiple Choice Question

10 x 1 = 10

(d)
Multiplication by fragmentation

(b)
Embryo development

(d)
The organism's habitat, physiology and genetic makeup

(b)
Gametes of parents have qualitatively different genetic composition

(b)
Palynology

(e)
Spermiogenesis

10.

1 Marks

5 x 1 = 5

11.

()
Juvenile phase

12.

()
Amoeba and Paramecium.

13.

()
Morphologically and genetically similar individuals produced as a result of asexual reproduction are clone.

14.

()
Pollen grain.

15.

()
A large number of male gametes fail to reach the female gametes; to compensate for this loss, male gametes are produced in several thousands.

Generic 2

5 x 2 = 10

16.

The different ways of asexual reproduction are:
(a) Fission (Binary and multiple fissions)
(b) Budding
(c) Fragmentation
(d) Gemmulation
(e) Vegetative propagation and (f) Sporulation.

17.

1. Zygote develops outside body, thus chances of survival are reduced.
2.Oviparous animals are at greater risk for survival because there is no parental care and production as in case of viviparous animals

18.

1. In haploid organisms, meiosis occurs during development of zygote.
2. It is the only diploid stage (formed by the fusion of two haploid gametes) in the life-cycle that can undergo meiosis.

19.

(i) Cucurbits are monoecious.
(ii) Date palm is dioecious and some of the plants bear exclusively pistillate flowers.

20.

1. In haploid organisms, showing haplontic life cycle, gamete formation involves only mitosis; the diploid zygote formed by the fusion of two haploid gametes, undergoes meiosis (zygotic meiosis).
2. In diploid organisms, showing diplontic or haplodiplontic life cycle, gamete formation involues meiosis (gametic meiosis) and haploid gametes are formedl; the diploid zygote undergoes mitosis to form diploid individuals.

Generic 3

5 x 3 = 15

21.

Gametes are normally always haploid (N) structure. In haploid organisms, they are never formed by meiosis. They are formed by mitotic divisionss, In haploid organism, there is zygotic meiosis i.e., it takes place in the zygote formed as a result of gametic fusion. Meiosis occurs in the zygote to form haploid spores which give rise to haploid organisms.

22.

Oviparous animals	Viviparous animals
These are the animals which lay fertilised or unfertilised eggs.	The are the animals which give birth to young ones.
Chances of survival are less as off-spring of oviparous animals are at a great risk as they are threatened by their predators and unfavourable environmental conditions, e.g. frogs, birds.	Chances of survival are hih as offspring of viviparous animals are protected by the parent organism from predators/enemies and unfavourable climate, eg. Human beings/mammals.

23.

External fertilisation	Internal fertilisation
When fusion of gametes (syngamy) occurs outside the body of the oranism, it is called external fertilisation.	When fusion of a gametes (syngamy) occurs inside the body of the oranism, it is called internal fertilisation.
A large number of gametes are released in the surrounding medium by such animals, e.g. frog and bonyfish.	The number of ova produced is less, but a large number of male gametes are formed, as they have to travel towards the ovum, e. birds, human beings, etc.
Chances of survival of offspring are less.	Chances of survival of offspring are high.

24.

Sporulation is the process in which the products of multiple fission become individually surrounded by a cyst wall before being released from the parent; each of them is a spore. The sporulation remain dormant during unfavourable conditions and germinate when conditions become favorable.

25.

Yeast reproduces asexually by budding under favourable conditions.

Generic 5

2 x 5 = 10

26.

(a) Grafting a branch from the tree of Ajay's house on a tree of Jagan's garden can be done.
(b) The part of the graft that forms the upper part is called scion and the part of the graft that becomes the supporting portion (the root and base), is called stock.
(i) The scion is selected from a superior quality plant (juicy, larger mango fruits) while the stock belongs to the plant to be improved.
(ii) The scion and stock should be of same diameter and slant cuts are made on both the branches.
(iii) The scion is kept on the stock, covered with grafting clay and polythene; it is tied well and arrangement of water supply/ moisturising is made.
(iv) After a few weeks, you will see buds and leaves appearing on scion.
(c)The mango tree will start producing flowers and fruits very early, may be in the next season itself. - Many branches can be grafted on the tree with poor quality mangoes.
(i) When grown from a seed it takes many years for the tree to produce fruits. - Sometimes the plant produced from the seed may not be of the same quality, as sexual reproduction results in variation.
(d) Values for friendship and generosity.

27.

(a) Frogs and Bony fish.
More gametes are produced by these organisms in order to enhance the chances of syngamy.
(b) A bird (parrot, crow, etc.), monkey and human beings.
1. The female gametes are retained inside the body of the female animals; they are produced in less numbers-one or a few.
2. The male gametes are motile; they are produced in sufficiently large numbers.