Biology

Biological Reproduction

806 Questions

Biological reproduction encompasses processes like asexual and sexual reproduction, alternation of generations, and specific mechanisms in plants and fungi. This topic is fundamental for biology paper preparation in various competitive exams. Practice these questions to solidify your understanding.

Asexual reproduction structuresPlant and fungi life cyclesCloning and fertilizationReproductive terminology

Biological Reproduction Questions

Multiple choice

The organisms that give birth to young ones are called _________

  1. Viviparous

  2. Ovoviviparous

  3. Oviparous

  4. Omnivorous
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Viviparous organisms give birth to live young rather than laying eggs. This is the reproductive strategy used by most mammals including humans. Oviparous organisms lay eggs, while ovoviviparous organisms retain eggs internally that hatch within the body. Omnivorous refers to diet, not reproduction.

Multiple choice

Asexual reproduction in Spirogyra mirabilis takes place by

  1. aplanospores

  2. azygospore

  3. statospores

  4. zoospores
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Asexual reproduction in Spirogyra mirabilis takes place by aplanospores. Under unfavourable conditions, the protoplast of each vegetative cell shrinks and develops a wall around it to form an aplanospore. Each non-motile aplanospore germinates to form a new filament.

Multiple choice

Akinetes are produced for asexual reproduction by

  1. Spirogyra articulate

  2. Spirogyra farlowi

  3. S. varians

  4. S. groenlandica
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Under unfavourable conditions, the vegetative cells of S. farlowii develop thick-walled cells called akinetes. After getting favourable conditions, each akinete germinates into a new filament.

Multiple choice

Sclariform conjugation takes place in Spirogyra when

  1. filaments lie adjacent to each other

  2. two filaments lie parallel to each other

  3. filaments lie horizontal to each other

  4. filaments forms a cross shape and lie on each other
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Sclariform conjugation takes place when filaments lie parallel to each other.

Multiple choice

Which of the following sentences about Scalariform conjugation is false?

  1. Scalariform conjugation takes place during day.

  2. Scalariform conjugation is a common process in heterothallic species of Spirogyra.

  3. Ladder formation takes place in Scalariform conjugation.

  4. Zygospores are in female gametangia.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Scalariform conjugation takes place at night.

Multiple choice

Zygospores are the product of

  1. asexual reproduction

  2. sexual reproduction

  3. vegetative reproduction

  4. unfavourable conditions
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Zygospores are the product of sexual reproduction. It is the only diploid phase of Spirogyra cell cycle.

Multiple choice

Aplanogametangia refers to

  1. conjugation tube formed in Scalariform conjugation

  2. two parallel strands of Spirogyra united with each other by a conjugation tube

  3. conjugation tube formed in lateral conjugation

  4. gametes produced in gametangia
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Two parallel strands of Spirogyra united with each other by a conjugation tube is referred to as aplanogametangia.

Multiple choice

In spirogyra, gametes are nonflagellated. During conjugation:

  1. only the male gamete move by amoeboid movement due to the activity of contractile vacuoles

  2. only the female gametes show amoeboid movement

  3. conjugation tube is formed, and both male and female gametes move

  4. both gametes undergo parthenogenesis
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In spirogyra, gametes are nonflagellated. During conjugation, only the male gamete moves by amoeboid movement due to the activity of contractile vacuoles.

Multiple choice

Scalariform conjugation in spirogyra is most common and takes place between:

  1. two adjacent cells of same filament

  2. two cells of different filament

  3. among three filaments

  4. within one cell of a filament
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Scalariform conjugation requires association of two different filaments lined side by side either partially or throughout their length. One cell each from opposite lined filaments emits tubular protuberances known as conjugation tubes, which elongate and fuse to make a passage called the conjugation canal. 

Multiple choice

Which of the following is correct about spirogyra?

  1. Filaments showing scalariform conjugation are homothallic.

  2. Filaments showing lateral conjugation are always homothallic.

  3. Filaments showing lateral conjugation may be homothallic.

  4. Asexual reproduction by zoospores.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In lateral conjugation, gametes are formed in a single filament. Two adjoining cells near the common transverse wall give out protuberances known as conjugation tubes, which further form the conjugation canal upon contact. The male cytoplasm migrates through the conjugation canal, fusing with the female. The rest of the process proceeds as in scalariform conjugation. Filaments showing lateral conjugation are always homothallic.

Multiple choice

Which of the following pairs of asexual reproductive structures is found in animals?

  1. Conidia and Buds

  2. Zoospores and Conidia

  3. Buds and Gemmules

  4. Gemmules and Zoospores

  5. Conidia and Zoospores
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Gemmules and buds are asexual reproductive structures found in animals. Gemmules are found in sponges such as Sycon. They are ball-like structures with protective covering, which consists of calcareous spicules. Budding is a common mode of asexual reproduction found in Hydra where outgrowths called buds, arise from the body of the organism, which grow and give rise to the new organisms.

Multiple choice

Match the following:

 
Name of organisms Mode of reproduction
a. Fungi 1. Regeneration
b. Yeasts 2. Spore formation
c. Planaria 3. Budding

  1. a - 1, b - 3, c - 2

  2. a - 3, b - 2, c - 1

  3. a - 1, b - 2, c - 3

  4. a - 2, b - 1, c - 3

  5. a - 2, b - 3, c - 1
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

This is the correct option. Fungi reproduce by the method of spore formation. Fungi multiply and spread easily due to the millions of asexual spores they produce. In lower organisms like yeast, the mode of reproduction is budding. In planaria, the mode of reproduction is regeneration. A fragmented organism regenerates the lost part of its body and becomes a new organism.