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Published on: 27/09/2019
Zoology - Reproduction in Organisms
Download Tamil Nadu 12th Standard Biology question papers, model tests, one-mark questions, important questions, and public exam papers in PDF format. Free study materials and answer keys for TN State Board students.
Questions + Answers key
Take MCQ Biology Test1.
______ is a seasonal breeder.
Poultry
Honey bees
Deers
Rabbit
2.
If the entire organism behaves as a gamete the Phenomenon is called _____
Autogamy
Syngamy
Morphallaxis
Hologamy
3.
4.
Animals giving birth to young ones:
Oviparous
Oviviviparous
Viviparous
Both a and b
5.
In which type of parthenogenesis are only males produced?
Arrhenotoky
Thelytoky
Amphitoky
Both a and b
6.
How are animals classified based on breeding periods?
7.
Define conjugation.
8.
What is morphallaxis?
9.
What is plasmotomy?
10.
Name the types of fission.
11.
What is the difference between syngamy and fertilization?
12.
Name an organism where cell division is itself a mode of reproduction.
13.
What is repeated fission?
14.
Why are the offsprings of oviparous animal at a greater risk as compared to offsprings of viviparous organisms?
15.
The unicellular organisms which reproduce by binary fission are considered immortal. Justify
16.
Which type of reproduction is effective -Asexual or sexual and why?
17.
18.
Given an account on following terms.
(a) Hologamy
(b) Isogamy
(c) Anisogamy
(d) Merogamy
(e) Paedogamy
19.
Differentiate between the following:
(a) Binary fission in amoeba and multiple fission in Plasmodium
(b) Budding in yeast and budding in Hydra
(c) Regeneration in lizard and Planaria
20.
Isogamy
21.
Autogamy
22.
Buds
23.
Conjugation
24.
Strobilation
1.
(c)
Deers
2.
(d)
Hologamy
3.
(c)
4.
(c)
Viviparous
5.
(a)
Arrhenotoky
6.
(i) On the basis of time, breeding animals are of two types: seasonal breeders and continuous breeders.
(ii) Seasonal breeders reproduce at particular period of the year such as frogs, lizards, most birds, deers etc.,
Continuous breeders continue to breed throughout their sexual maturity. E.g. honey bees, poultry, rabbit etc.
7.
conjugation is the temporary union of the two individuals of the same species. During their union both individuals, called the conjugants exchange certain amount of nuclear material (DNA) and then get separated. E.g. Paramecium
8.
It is a type of regeneration. In morphallaxis the whole body grows from a small fragment. E.g. Hydra.
9.
(i) Plasmotomy is the division of multinucleated parent into many multinucleate daughter individuals, with the division of nuclei.
(ii) Nuclear division occurs later to maintain normal number of nuclei (e,g:) Opalina and Pelomyxa.
(iii) Plasmotomy occurs in Opalina and Pelomyxa.
(iv) It is a method of asexual reproduction
10.
There are five types of fission. They are Binary fission, multiple fission, sporulation, and strobilation.
11.
| syngamy | fertilization |
| It is the fusion of two haploid gametes to form a diploid zygote | It is the act (or) process of rendering fertile zygote as the result of Fertilization |
12.
In monocellular organs cell division is itself a mode of reproduction. (e.g:) Bacteria, Euglena and Amoeba.
13.
If multiple fission produces four or many daughter individuals by equal cell division and the young ones do not separate until the process is complete, then this division is called repeated fission. E.g. Vorticella.
14.
Oviparous animals lay eggs outside their body. These eggs are exposed to various environmental conditions and may be eaten by predators also. They face lot of risks until the young ones hatche. But the offsprings of viviparous animals are more safe and protected in the maternal womb until they are born.
15.
1. In unicellular organism there is no special structure for reproduction.
2. In binary fission the entire parent body constitute the reproductive unit and disappears when its division into two daughter unicellular cell is completed.
3. These two daughter cells function as two new individuals.
4. There is no remains of parent body cell and parent cannot be said to have died.
5. In fact after binary fission parent continues living as two daughter individual.
Hence, the unicellular organisms which undergo binary fission are called immortal (no natural death).
16.
1. Sexual reproduction is considered to be a better mode of reproduction because it creates a hybrid that has more vigor than the parents.
2. It also creates the variation in off springs making its survival better.
3. The fact that most of the eukaryotes reproduce sexually in evidence of its evolutionary success.
4. In many animals, it is actually the only mode of reproduction.
17.
18.
(a) Hologamy: In Hologamy, the adult individuals do not produce gametes, but they themselves act as gametes and fuse to form new individuals.
E.g: Trichonympha
(b) Isogamy: Fusion of morphologically & physiologically similar gametes.
E.g: Monocystis
(c) Anisogamy: Fusion of morphologically & physiologically dissimilar gametes.
Eg: Vertebrates.
(d) Merogamy: Fusion of small-sized morphologically different gametes (microgametes)
(e) Paedogamy: Fusion of young individuals produced immediately after the mitotic division of adult parent cell.
19.
(a)
| Binary Fission in Amoeba | Multiple fission in Plasmodium |
| lt results in the production of two individuals from a single parent. | It results in the production of several individuals |
| lt occurs under favourable conditions | It occurs both under favourable and unfavourable conditions |
| Nucleus of the parent cell divides only once to form two daughter nuclei | Nucleus of the parent cell undergoes repeated divisions to form a number of daughter nuclei |
| Cytoplasm divides after nuclear division | Cytoplasm does not divide after each nuclear division but divides during favourable condition |
| No part of parent body is left unused (e,g: Amoeba) | A part of the body (covering and residuai cytoplasm) is left unused. (e,g: Paramecium) |
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(b) Budding in yeast and budding in hydra
| Budding in Yeast | Budding in Hydra |
| During budding the cell wall of the parent cell bulges out in the form of an out growth as bud | During budding the ectoderm cells increase and form a small elevation on the body surface as bud. |
| The parent nucleus divides into two daughter nuclei one of which migrates into bud. | Ectoderm and endoderm are pushed out to form the bud. The bud contains an interior lumen in continuation with parent's gastro vascular cavity (coelenteron) |
| As the bud enlarges and is fully formed, it is separated from the parentcell and grows into mature yeast. Sometimes a bud may produce another bud over it which is still attached to parent cell forming a false mycelium (or) pseudomycelium | The bud enlarges, develops a mouth and a circle of tentacles at its free end. When fully grown, the bud constricts at the base and finally separates from the parent body and leads an independent life |
(c) Regeneration is regrowth in the injured region
| Regeneration in Lizard | Regeneration in Planaria |
| This type of regeneration comes under epimorphosis type. | This type of regeneration comes under morphallaxis type |
| Several body parts can develop. | When the body is cut into several pieces, each piece can regenerate the lost parts and develops into a whole individual |
20.
Monocystis
21.
Paramecium
22.
Hydra
23.
Bacteria
24.
Aurelia
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