Tag: biology

Questions Related to biology

Which vitamin is synthesised by the bacteria in human gut?

biology biotechnology and genetic engineering stds and infertility gm crops biotechnology

  1. Vitamin A

  2. Vitamin C

  3. Vitamin D

  4. Vitamin K

Show answer
Correct Option: D
Explanation:

Escherichia coli are Gram-negative, facultative aerobic bacteria. They are common inhabitant of human gut. These strains of E. coli are harmless. They form the part of the normal microbiota of the intestine. They live in symbiotic association. They benefit hosts by producing vitamin K$ _2$ and preventing colonization of the intestine with pathogenic bacteria.

Thus, the correct answer is 'Vitamin K.'

Human proteins can be produced in milk or semen of farm animals

biology biotechnology and genetic engineering stds and infertility gm crops biotechnology

  1. True

  2. False, proteins cannot be produced in semen

  3. False, proteins cannot be produced in milk

  4. False, animals are not used for protein production

Show answer
Correct Option: A
Explanation:
Milk proteins contain all 9 essential amino acids required by humans. Milk proteins are synthesized in the mammary gland, but 60% of the amino acids used to build the proteins are obtained from the cow's diet. So we can get protein from the cow's milk too.
So the correct option is 'true'.

Which one of the following combinations of microbes is responsible for the formation and flavour of Yoghurt?

biology biotechnology and genetic engineering stds and infertility gm crops biotechnology

  1. Lactobacillus casei and Streptococcus thermopiles

  2. Rhizobium maillot and Azotobacter species

  3. Ebodoiquerillurs rub urn and Scincealla typhosa

  4. Bacillus substiles and Escherichia coli

Show answer
Correct Option: A

Making of cheese from pasteurised milk is carried out by the enzyme

biology biotechnology and genetic engineering stds and infertility gm crops biotechnology

  1. Protease

  2. Pectinase

  3. Amylase

  4. Lipase

Show answer
Correct Option: A

Which is generally regarded is the first product of ancient biotechnology?

biology biotechnology and genetic engineering stds and infertility gm crops biotechnology

  1. Rubber

  2. Opium

  3. Alcohol

  4. Wax

Show answer
Correct Option: C
Explanation:
Our early ancestors used microorganisms to make cheese, yoghurt and bread. They also made alcoholic drinks like beer and wine. All of these foods and drinks are made by fermentation. Fermentation is the process that many microorganisms (yeasts, moulds and bacteria) use to convert sugars into energy. The products generated from fermentation affect the nature of the food that the microorganism is in - carbon dioxide causes bread to rise, lactic acid makes yoghurt sour, and alcohol is produced in the formation of beer and wine. Fermentation was probably discovered by accident, and our early ancestors didn’t know how it worked. Some societies thought fermentation was a miracle or gift from their god.
So the correct option is 'alcohol'.

Yeast yields

biology biotechnology and genetic engineering stds and infertility gm crops biotechnology

  1. Vitamin ${ B } _{ 12 }$

  2. Tocopherol

  3. Riboflavin

  4. Ascorbic acid

Show answer
Correct Option: C
Explanation:

Riboflavin (vitamin B$ _{2}$) is part of the vitamin B group. It is the central component of the cofactors FAD and FMN and as such required for a variety of flavoprotein enzyme reactions including activation of other vitamins. Various biotechnological processes have been developed for industrial scale riboflavin biosynthesis using different microorganisms, including filamentous fungi such as Ashbya gossypii, Candida famata and Candida flaveri, as well as the bacteria Corynebacterium ammoniagenes and Bacillus subtilis. Strains of yeast of the species Candida famata also used to synthesis ribiflavin. Thus, option C is correct. Microorganism Acetobacter is used to yield ascorbic acid. Thus, option D is wrong. Yeast does not yields tocopherol and vitamin B$ _{12}$. Thus, option A and B are wrong.

Which of the following is used to promote the growth of new blood vessels, thus help in wound healing?

biology biotechnology and genetic engineering stds and infertility gm crops biotechnology

  1. Humulin

  2. TPA

  3. TGF-$\beta$

  4. $\alpha$-1 antitrypsin

Show answer
Correct Option: C

Match the Column-I & Column-II.

(i) Auxin (A) Ripening of fruit
(ii) ABA (B) Bolting
(iii) Gibberellin (C) Sensitivity against adverse conditions
(iv) Ethephon (D) parthenocarpy in tomato
biology plant growth control of blood glucose hormones in human reproduction testes and ovary

  1. i-C, ii-D, iii-B, iv-A

  2. i-D, ii-C, iii-A, iv-B

  3. i-D, ii-C, iii-B, iv-A

  4. i-A, ii-C, iii-B, iv-D

Show answer
Correct Option: C
Explanation:

  • (i) Auxin - (D) parthenocarpy in tomato -Auxins are generally produced by the growing apices of the stems and roots, from where they migrate to the regions of their action. Auxins also induce parthenocarpy in
tomatoes. 
  • (ii) ABA - (C) Sensitivity against adverse conditions -ABA(Abscisic acid) acts as a general plant growth inhibitor and an inhibitor of plant metabolism.ABA regulates sensitivity against adverse conditions i.e ABA stimulates the closure of stomata in the epidermis and increases the tolerance of plants to various kind of stresses. Therefore, it is also called the stress hormone.
  • (iii) Gibberellin - (B) Bolting -Gibberellins promotes bolting
(internode elongation just prior to flowering) in beet, cabbages and many
plants with rosette habit.
  • (iv) Ethephon - (A) Ripening of fruit - Ethephon in an aqueous solution is readily absorbed and transported within the plant and releases ethylene slowly. Ethephon hastens fruit ripening in tomatoes and apples.
  • So, the correct answer is 'i-D, ii-C, iii-B, iv-A'.

Myelin sheath is covering of

biology control and co-ordination in plants and animals control of blood glucose hormones in human reproduction testes and ovary

  1. Muscle cells

  2. Axon of neurons

  3. Blood vessels

  4. Osteocytes

Show answer
Correct Option: B
Explanation:

A neuron can be defined as a long cytoplasmic process of the cell body, which transmits the impulse from the cell body to other neurons is termed. The axon is covered by a lipid-rich membrane, called myelin sheath. The myelin sheath is formed by Schwann cells and each Schwann cell covers a part of the axon.
Thus, the correct answer is the option (B), 'Axon of neurons'.

Selaginella and Salvinia are considered to represent a significant step toward the evolution of seed habit because 

classification of pteridophytes kingdom plantae plant kingdom biology

  1. Embryo develops in female gametophyte which is retained on parent sporophyte

  2. Female gametophyte is free and gets dispersed like seeds

  3. Female gametophyte lacks archegonia

  4. Megaspore possess endosperm and embryo surrounded by seed coat

Show answer
Correct Option: A
Explanation:

Genera like Selaginella and Salvinia which produce two kinds of spores, macro (large) and small (micro) spores are known as heterosporous. Microspore and macrospore germinate and gives rise to male and female gametophyte respectively. The female gametophytes in these plants are retained on the parent sporophyte for a variable period. The development of the zygote into young embryo takes place within the female gametophytes. This event is a precursor to the seed habits considered an important step in evolution. So, the correct answer is 'Embryo develops in female gametophyte which is retained on parent sporophyte'.