Tag: biology

Questions Related to biology

How does the sperm break through the egg cell membrane? Choose the option you think is right.

biology human system reproductive systems different stages of growth reproductive system in humans

  1. Tears a hole in the membrane

  2. Dissolves the membrane with chemicals

  3. Bites through the membrane with teeth

  4. Squeezes through gaps in the membrane

Show answer
Correct Option: A

During the development of embryo which of the following occur first 

biology division for growth and reproduction reproductive systems different stages of growth reproductive system in humans human system

  1. Differentiation of tissue

  2. Differentiation of cells

  3. Differentiation of organs

  4. Differentiation of organ system

Show answer
Correct Option: B
Explanation:

Blastula differentiate into various regions and cells (blastomeres) of a particular region form a particular part of adult body, hence these areas are called presumptive areas and at this stage if cells of a particular area removed the adult lacks a particular part from its body.

Which distinguishes a morula from a blastula 

biology division for growth and reproduction reproductive systems different stages of growth reproductive system in humans human system

  1. Presence of more yolk

  2. Absence of yolk

  3. Presence of a cavity

  4. Absence of a cavity

Show answer
Correct Option: D
Explanation:

In microlecithal eggs or alecithal eggs, the cleavage results in the production of closely packed blastomeres. The stage in which solid mass of blastomeres appears is said to be morula, whereas blastula is hollow with a cavity known as blastocoel.

The events in sexual reproduction are
(i) pre-fertilisation
(ii) fertilisation
(iii) post-fertilisation
The sequential order of their occurence is

biology division for growth and reproduction reproductive systems different stages of growth reproductive system in humans human system

  1. (ii) - (i) - (i)

  2. (ii) - (ii) - (i)

  3. (i) - (ii) - (iii)

  4. (i) - (iii) - (iv)

Show answer
Correct Option: C
Explanation:

In spite of their morphological, anatomical and physiological differences, the fundamental events in sexual reproduction are the same. These events can be categorized as follows:

1. Pre-fertilization events: All the preparatory events which occur before the fusion of gametes are called pre-fertilization events. These include Gametogenesis and gamete transfer.
2. Fertilization: Fusion of two entire gametes ( one male and another female) to form a zygote.
3. Post-fertilization: All the events that occur during sexual reproduction after the fusion of gametes are called post-fertilization events.
So, the correct answer is '(i)-(ii)- (iii)'.

Match column I with column II and select the correct options from the codes given.

Column I Column II
A. Hypothalamus (i) Sperm lysins
B. Acrosome (ii) Estrogen
C. Graafian follicle (iii) Relaxin
D. Leydig's cells (iv) GnRH
E. Parturition (v) Testosterone
biology division for growth and reproduction reproductive systems different stages of growth reproductive system in humans human system

  1. A - (iv), B - (i), C - (ii), D - (iii), E - (v)

  2. A - (ii), B - (i), C - (iv), D - (iii), E - (v)

  3. A - (ii), B - (i), C - (v), D - (iv), E - (iii)

  4. A - (iv), B - (i), C - (ii), D - (v), E - (iii)

Show answer
Correct Option: D
Explanation:

The hypothalamus is a small region of the brain. It's located at the base of the brain, near the pituitary gland. It secretes hypothalamic hormone such as the GnRH or Gonadotropin stimulating hormone which further has effects on the pituitary gland. The acrosome is the anterior covering on the head of the sperm that consists of enzymes called lysins that can lyse the ovum membrane to penetrate and fertilize it. A Graafian follicle is a developed tertiary follicle and is responsible for the ovulation that occurs as a result of the surge in FSH and LH levels responsible for estrogen production. Leydig cells in the seminiferous tubules are responsible for the secretion of androgens such as testosterone. Parturition is the process of the delivery of the fetus and during this process, Relaxin is a hormone produced by the ovary and the placenta with important effects in the female reproductive system and during pregnancy. 

So, the correct option is 'A - (iv), B - (i), C - (ii), D - (v), E - (iii)'.

Match column I (terms) with column II (definitions) and select the correct options from the codes given.

Column I Column II
A. Parturition (i) Attachment of embryo to endometrium
B. Gestation (ii) Release of egg from Graafian follicle
C. Ovulation (iii) Delivery of baby from uterus
D. Implantation (iv) Duration between pregnancy and birth
E. Conception (v) Formation of zygote by fusion of the egg and sperm
(vi) Stoppage of ovulation and menstruation
biology division for growth and reproduction reproductive systems different stages of growth reproductive system in humans human system

  1. A - (ii), B - (iv), C - (i), D - (v), E - (vi)

  2. A - (iv), B - (iii), C - (i), D - (v), E - (ii)

  3. A - (v), B - (vi), C - (ii), D - (iii), E - (iv)

  4. A - (iii), B - (iv), C - (ii), D - (i), E - (v)

Show answer
Correct Option: D
Explanation:

Parturition is the delivery or childbirth of baby from the uterus. Gestation is the period of development during the carrying of an embryo or fetus inside viviparous animals and the duration between pregnancy and birth. Ovulation is the process of release of the ovum from the Graafian follicle as it ruptures. Implantation is the process of attachment of the zygote to the endometrial lining of the uterus. Conception refers to the post-fertilization fusion of the egg and sperm into the zygote.

So, the correct option is 'A - (iii), B - (iv), C - (ii), D - (i), E - (v)'.

Kohler and Milstein developed biotechnology for production of

biology immunity monoclonal antibodies antibody production and vaccination biotechnology

  1. Modern vaccines

  2. Immobilised enzymes

  3. Monoclonal antibodies

  4. Myelomas

Show answer
Correct Option: C
Explanation:

Monoclonal antibodies are monospecific antibodies that are made by identical immune cells that are all clones of a unique parent cell. In 1975, Georges Kohler and Cesar Milstein succeeded in making fusions of myeloma cell lines with B cells to produce hybridomas that made antibodies to known antigens. Monoclonal antibodies were first produced by applying the techniques of somatic cell genetics to antibody-producing cells. The cells that produce antibodies (B cells) are short-lived in culture. Thus, attempts to maintain B cells in culture and harvest antibody specificities failed for many years until Cesar Milstein and George Koehler succeeded in immortalising B cells via somatic cell hybridisation.

Hybridomas are used for

biology immunity monoclonal antibodies antibody production and vaccination biotechnology

  1. Synthesis of antibiotics

  2. Killing cancer cells

  3. Synthesis of monoclonal (somaclonal) antibodies

  4. Production of somatic hybrids

Show answer
Correct Option: C
Explanation:

Hybridoma technology is a technology of forming hybrid cell lines (called hybridomas) by fusing an antibody-producing B cell with a myeloma (B cell cancer) cell that is selected for its ability to grow in tissue culture and for an absence of antibody chain synthesis. The antibodies produced by the hybridoma are all of a single specificity and are therefore monoclonal antibodies. So, the correct answer is option C.

The technique of production of monoclonal antibodies was developed by

biology immunity monoclonal antibodies antibody production and vaccination biotechnology

  1. Watson and Crick

  2. Milstein and Kohler

  3. Bentham and Hooker

  4. Meischer

Show answer
Correct Option: B
Explanation:

Milstein and Kohler described the first technique developed for stable monoclonal antibody production.

Fluorescent dye bonded to monoclonal antibodies is used to locate particular.

biology immunity monoclonal antibodies antibody production and vaccination biotechnology

  1. Cell proteins

  2. Cells

  3. Diseased parts

  4. Organs of defence

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Correct Option: A