Tag: biology

Quizzes (1160) Questions (12174)

Questions Related to biology

Multiple choice biology plant kingdom alternation of generation in angiosperms alternation of generation angiosperms

Which one of the following is not a common feature of gametophyte selfincompatibility systems?

  1. Pollen is $3$-celled

  2. Pistil is wet

  3. Rejection reaction occurs in the style

  4. In vitro germination of pollen is easy
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In gametophytic self-incompatibility, the pollen is typically 2-celled at the time of shedding, whereas in sporophytic self-incompatibility, the pollen is often 3-celled.

Multiple choice biology plant kingdom alternation of generation in angiosperms alternation of generation angiosperms

Aposporously formed gametophytes in Dryopetris will bear gametes that are ____________.

  1. Haploid

  2. Diploid

  3. Triploid

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

Apospory is the development of a gametophyte directly from the vegetative cells of a sporophyte without meiosis. Since the sporophyte is diploid (2n), the resulting aposporously formed gametophyte is also diploid, and therefore its gametes will be diploid.

Multiple choice biology plant kingdom alternation of generation in angiosperms alternation of generation angiosperms

Gametophyte self incompatibility does not differ from saprophytic self incompatibility in that.

  1. There is co dominance of self incompatibility alleles
  2. Both give $50\%$ functional. Pollen in pollinations on some other plants

  3. There is breakdown of incompatibility on induction of polyploidy

  4. There is complete failure of seed set on self pollination
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Both gametophytic and sporophytic self-incompatibility systems involve the interaction of alleles that prevent self-fertilization, and both can be overcome by polyploidy, which often leads to the breakdown of the incompatibility reaction.

Multiple choice biology plant kingdom alternation of generation in angiosperms alternation of generation angiosperms

Read the given paragraph.
Where there is alternation of generations, the haploid multicellular plant is called a   (i)   and the diploid multicellular plant is called   (ii)   .    (iii)   generation is the dominant phase in algae showing haplontic type of life cycle. Bryophytes and pteridophytes usually possess    (iv)   types of life cycle.
Select the correct sequence of terms to complete the above paragraph.

  1. (i)-Sporophyte, (ii)-Gametophyte, (iii)-Gametophyte, (iv)-Diplontic

  2. (i)-Gametophyte, (ii)-Sporophyte, (iii)-Sporophyte, (iv)-Haplontic

  3. (i)-Sporophyte, (ii)-Gametophyte, (iii)-Sporophyte, (iv)-Haplodiplontic

  4. (i)-Gametophyte, (ii)-Sporophyte, (iii)-Gametophyte, (iv)-Haplodiplontic
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In alternation of generations, the haploid plant is the gametophyte and the diploid is the sporophyte. Algae showing haplontic cycles have a dominant gametophyte. Bryophytes and pteridophytes exhibit a haplodiplontic life cycle.

Multiple choice biology plant kingdom alternation of generation in angiosperms alternation of generation angiosperms

Read the given statements and select the correct option. 
Statement 1 : Bryophytes show alternation of generation.
Statement 2 : A haploid gametophytic generation and a diploid sporophytic generation alternate in the life cycle.

  1. Both statements 1 and 2 are correct.

  2. Statement 1 is correct but statement 2 is incorrect.

  3. Statement 1 is incorrect but statement 2 is correct.

  4. Both statements 1 and 2 are incorrect.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Following are the correct statements: 

(i) Bryophytes show alternation of generation.
(ii) A haploid gametophytic generation and a diploid sporophytic generation alternate in the life cycle.
So, the correct answer is (a).

Multiple choice biology plant kingdom alternation of generation in angiosperms alternation of generation angiosperms

In moss,antheridia and archegonia occur at the tips of two different branches of the same plant.The condition is called

  1. Monoecious and autoecious

  2. Monoecious and paroicous

  3. Monoecious and synoicous

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

In mosses, when antheridia and archegonia are on different branches of the same plant, the condition is monoecious (since both sexes are on one plant) and specifically paroicous (if they are on the same branch) or autoecious (if on different branches). Given the options, 'monoecious and paroicous' is the standard classification for this specific arrangement.

Multiple choice biology plant kingdom alternation of generation in angiosperms alternation of generation angiosperms

Which of the following is a diploid?

  1. Capsule of moss

  2. Gametophyte. archegonia and egg of moss

  3. Gametophyte, antheridia and sperm of moss

  4. Gametophyte and spore of moss
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Mosses have neither pollen nor flowers and rely on water to carry the male gametes (the sperm) to the female gametes (the eggs). The spore capsules are produced after the sperms have fertilized the eggs. As they are produced after fertilisation, these spore capsules are diploid.

So, the correct option is 'Capsule of moss'.

Multiple choice biology plant kingdom alternation of generation in angiosperms alternation of generation angiosperms

Which one has the larges gametophyte?

  1. Cycas

  2. Angiosperm

  3. Selaginella

  4. Moss
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

In bryophytes and pteridophytes and gymnosperms the male and female gametophytes to not have an independent free-living existence. They remain within the sporophyte. The gametophytes are quite large in Bryophytes as compared to other phyla like pteridophytes or angiosperms.

So, the correct option is 'Moss'

Multiple choice biology biotechnology and genetic engineering making use of enzymes genetic technology genetic engineering

The centre of origin of wheat is

  1. Southeast Asia

  2. Southwest Asia

  3. Asia minor and Afganistan

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Wheat is grown on more land area worldwide than any other crop and is a close third to rice and corn in total world production. Wheat is well adapted to harsh environments and is mostly grown on wind swept areas that are too dry and too cold for the more tropically inclined rice and corn, which do best at intermediate temperature levels. 

Wheat is believed to have originated in southwestern Asia. Some of the earliest remains of the crop have been found in Syria, Jordan and Turkey. Primitive relatives of present day wheat have been discovered in some of the oldest excavations of the world in eastern Iraq, which date back 9,000 years. Thus, the correct answer is option B.