Tag: biology

Questions Related to biology

Motile sperms are absent in _______________.

  1. Rhizopus

  2. Funaria

  3. Fern

  4. Cycas


Correct Option: A
Explanation:

Motile sperms are absent in Rhizopus. In Rhizopus, gametangial copulation takes place. The terminal part of sub aerial hyphae acts as coenogametes which fuse to form a diploid zygote and then a resting spore called as zygospore. It contains several diploid nuclei with reserve material. It undergoes meiosis to form spores which on germination give rise to new mycelium.

Therefore, the correct answer is option A.

Select the correct match of algal class and its characteristic flagellation.

  1. Chlorophyceae - 2-8 equal, apical

  2. Phaeophyceae - 2, unequal, lateral

  3. Rhodophyceae - Absent

  4. All of these


Correct Option: D
Explanation:

Correct match of algal class and its characteristic flagellation: 

Chlorophyceae - 2-8 equal, apical
Phaeophyceae - 2, unequal, lateral
Rhodophyceae - Absent
So, the correct answer is (d).

In Chlamydomonas(a green algae) the number of chloroplast per cell is?

  1. $1$

  2. $2$

  3. $100$

  4. $1000$


Correct Option: A

Zoospores produced in Ectocarpus are?

  1. Motile

  2. Thick walled

  3. Pyriform

  4. Both $(1)$ and $(3)$


Correct Option: A

The microsporangia of anther develop and become?

  1. Zoospores

  2. Pollen sacs

  3. Generative cell

  4. MMC


Correct Option: A

'Minute floating' plants are mainly

  1. Algae

  2. Bacteria

  3. Virus

  4. Fungi


Correct Option: A

Name the phenomenon that governs the following-

  1. Green beetels living in green bushes are not eaten by the crows

  2. All tall plants are obtained in $F _1$ generation, upon crossing pure tall and dwarf pea plant.

  3. Tails of mice were surgically removed for several generation ; still mice have tails in the following generation .

  4. Numbers of blue beetles on green bushes increase in a fur distant location than green beetles on green bushes, isolated by a river.

  5. A migrant beetle reproduces with the local population ; as a result genes of migrant beetle enter the new population.


Correct Option: A
Explanation:

Green beetles living in green bushes are camouflaged by their surroundings and are hence not eaten by the crows. This is a defense strategy employed by the beetles in order to escape predation. In the F1 generation crossing homozygous dominant (pure tall) and homozygous recessive (pure dwarf) plants will result in the heterozygous condition (Tt) with a phenotype of all tall plants as they will still have the dominant genotype. Removal of tails cannot be passed on from one generation to another, as it is not a heritable change and not a part of the genetic makeup of the organism. The isolation of an organism by a geographical barrier such as a river is called allopatry and hence governs the speciation of a sub-population such as blue beetles from green beetles. When a  migrant beetle reproduces with the local population the genes of migrant beetle enter the new population by the means of gene flow (also known as gene migration or allele flow) is the transfer of genetic variation from one population to another.  

So the correct answer is Green beetles living in green bushes are not eaten by the crows.

Major photosynthetic pigments in green algae are

  1. Chl $a$ and $b$

  2. Chl $a$, $c$ and fucoxanthin

  3. Chl $a$, $d$ and phycoerythrin

  4. Chl $a$ and $c$


Correct Option: A

What are examples of primary producers?

  1. Omnivores

  2. Animals

  3. Green plants and Algae

  4. Carnivores


Correct Option: C
Explanation:

Primary producers in a terrestrial ecosystem live in and around the organic matter. Since they are not mobile, they live and grow where there are nutrients to sustain them. The primary producers include green plants, lichens, moss, bacteria, and algae. 

The zygospore of Sporogyra after undergoing a rest germinates into a unicellular structure called ____________.

  1. Sporohyte plant

  2. Germ cell

  3. Germ tube

  4. Germ plant


Correct Option: C
Explanation:

Spirogyra is a freshwater green alga. During its sexual cycle, the zygospore is formed which is considered as the only diploid phase in its life cycle. In favourable conditions, When zygospore burts and it is one haploid nucleus form germ tube.

The correct answer is C.