Biology

Biological Reproduction

762 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 two modes of reproduction are _____________.

  1. asexual and bisexual

  2. asexual and sexual

  3. bisexual and sexual

  4. unisexual and bisexual
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

In biology, reproduction occurs through two fundamental modes: asexual reproduction (involving one parent) and sexual reproduction (involving two parents). Bisexual and unisexual refer to organism types, not reproductive modes.

Multiple choice

Budding in hydra and yeast occurs by ______________.

  1. longitudinal division of parent body into two

  2. transverse division of parent body into two

  3. formation of an outgrowth on the parent body

  4. formation of spores in the parent body
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Budding in organisms like hydra and yeast involves the formation of an outgrowth (bud) on the parent body, which gradually grows and eventually separates to become a new individual. This is distinct from longitudinal or transverse division.

Multiple choice

Asexual reproduction involves ____________________.

  1. introduction of variations

  2. spore formation

  3. gamete formation

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

Spore formation is a method of asexual reproduction where organisms produce specialized reproductive cells (spores) that develop into new individuals without fertilization. Other options like gamete formation and meiosis are part of sexual reproduction.

Multiple choice

The oocysts of Cystoisospora belli are long and oval-shaped. Which among the following statements regarding the life cycle of Cystoisospora belli is incorrect?

  1. Trophozoites develop into schizonts.

  2. The sporozoites invade the epithelial cells of the allimentary.

  3. Transmission occurs when these mature oocysts are ingested.

  4. An oocyst with two sporoblasts is released in the stool of infected person.

  5. Each sporocyst divides twice, resulting in four sporozoites.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

An oocyst with one sporoblast is released in stool of infected person.After the oocyst has been released, the sporoblast matures further and divides into two.

Multiple choice

The life cycle of dinoflagellates is multi-staged. Which among the following statements regarding the life cycle of dinoflagellates is false?

  1. Vegetative fission dominates yielding motile diploid schizonts.

  2. The schizonts act as gametes.

  3. The diploid zygote constructs a new theca and resumes its motility as a planozygote.

  4. In several species, the zygote theca becomes much thicker and considerably larger than the vegetative theca.

  5. Following a period of obligate dormancy, the protoplast excysts.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

During periods favoured by rapid growth and population expansion, vegetative fission dominates yielding motile haploid schizonts.

Multiple choice

The most common mode of reproduction in diatoms is asexual. Which among the following diatoms differs from closely related species by its sexual reproduction and movement in response to light?

  1. Craspedodiscus elegans

  2. Bacteriastrum delicatulum

  3. Craticula

  4. Tabellaria

  5. Pinnularia
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Craticula is a genus of diatom that lies on or in the top layers of sediments in the freshwater to brackish water environments it inhabits.In addition to frustule morphology the genus differs from closely related species by its sexual reproduction and movement in response to light.

Multiple choice

Which among the following statements does not characterise diatoms?

  1. Araphid pennate diatoms are capable of gliding movement.

  2. The daughter cell that receives the original epitheca remains of the same size as the parent.

  3. The most common mode of reproduction in diatoms is asexual by cell division.

  4. The epicingulum and hypocingulum are collectively known as the girdle.

  5. The frustule is frequently in a high state of differentiation in diatoms.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Raphid pennate diatoms are capable of gliding movement that is caused by the secretion of mucopolysaccharides, derived from vesicles or crystalline bodies, through the raphe. Araphid pennate diatoms lack a raphe and posses a central, unornamented area known as the sternum or pseudoraphe. No centric diatom has a raphe.

Multiple choice

Which among the following statements regarding the life cycle of red algae is FALSE?

  1. The spores of a sporophyte produce either of the tetrasporophytes.

  2. The gametophyte may replicate using carpospores.

  3. Carpospores may also germinate directly into thalloid gametophytes.

  4. They display alternation of generations.

  5. Red algae lack motile sperm.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The gametophyte may replicate using monospores, but produces sperm in spermatangia, and eggs in carpogonium.

Multiple choice

Regarding the reproduction in sponges, which of the following statements is INCORRECT?

  1. In the sponges the sperm are produced by collencytes.

  2. During spawning, sperm burst out of their cysts and are expelled via the osculum.

  3. Gemmules are aggregates of sponge tissue and food.

  4. Only a sponge fragment containing both collencytes and archeocytes will regenerate.

  5. Freshwater gemmules may also include phytosynthesising symbionts.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Most sponges are hermaphrodites (function as both sexes simultaneously), although sponges have no gonads (reproductive organs). Sperm are produced by choanocytes or entire choanocyte chambers that sink into the mesohyl and form spermatic cysts while eggs are formed by transformation of archeocytes, or of choanocytes in some species.

Multiple choice

Spirogyra reproduces by ___________.

  1. budding

  2. fragmentation

  3. gamete formation

  4. vegetative propogation

  5. spore formation
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Yes, it is the correct answer. The plant body is divided into smaller fragments. Each fragment then develops into a new plant.

Multiple choice

In which type of reproduction, two parents are involved?

  1. Budding

  2. Fragmentation

  3. Spore formation

  4. Vegetative propogation

  5. Sexual
Reveal answer Fill a bubble to check yourself
E Correct answer
Explanation

Yes, when two parents are involved in the process, it is called sexual reproduction. Two gametes, viz. male and female gametes, are formed.

Multiple choice

Which of the following events takes place in triparental mating?

  1. Two donor cells conjugate simultaneously with a host cell.

  2. One bacterial strain assists another in transferring genetic material to a third bacterial strain.

  3. Host cell receives the genetic material from three donor cells.

  4. Integrated plasmid, along with an external DNA, fuses with the host DNA.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Triparental mating is a form of bacterial conjugation where a conjugative plasmid present in one bacterial strain assists the transfer of a mobilisable plasmid present in a second bacterial strain into a third bacterial strain. In other words, one bacterial strain helps the another in transferring genetic material to a third bacterial strain.

Multiple choice

The process of embryo formation without fertilization is known as

  1. apospory

  2. apogamy

  3. parthenocarpy

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

Apogamy is the development of a sporophyte (embryo) from a gametophyte without fertilization. Apospory is gametophyte from sporophyte, parthenocarpy is fruit development without fertilization (no embryo formation necessarily), and polyembryony is multiple embryo formation.

Multiple choice

The diploidy in higher animals is maintained by

  1. plasmogamy

  2. syngamy

  3. dichogamy

  4. none of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Diploidy (2n chromosome number) in higher animals is maintained by syngamy - the fusion of male and female gametes during fertilization. This restores the diploid state in the zygote. Plasmogamy is fungal cytoplasm fusion, and dichogamy refers to timing differences in sexual organ maturity.