NEET Test 136

Johann Mendel, considered the father of genetics, gave the observation and theories of inheritance of characteristics. He made the bases of his conclusions on experiments conducted on Pisum sativum. In the plant, he had considered seven characteristics - seed shape, seed colour, pod shape, pod colour, stem height, flower colour, and flower position.

Asexual Reproduction:

• It is the process in which a new individual is formed by the involvement of a single parent with or without the involvement of the gamete formation.
• The individuals produced are genetically and morphologically similar.
• It occurs in unicellular organisms where cells divide by mitotic division and no fertilization takes place. The division occurs very rapidly.

Types Of Asexual Reproduction:

• Binary Fission-
  • It is seen in amoeba and euglena.
  • The parent cell undergoes mitosis and increases in size. The nucleus also divides.
  • Two identical daughter cells are obtained, each containing a nucleus. Prokaryotes like bacteria majorly reproduce by binary fission.
• Budding-
  • In this, the offspring grows out of the body of the parent.
  • It remains attached to the parent until it matures.
  • After maturation, it detached itself from the parent and lives as an individual organism.
  • This form of reproduction is most common in Hydras.
• Fragmentation-
  • In some organisms like Planarians, when the body of an organism breaks into several pieces each piece grows into an individual offspring. This is known as fragmentation.
  • It can occur through accidental damage by predators or otherwise, or as a natural form of reproduction.
  • In few animals such as seastar, a broken arm grows into a complete organism.
• Regeneration-
  • It is a modified form of fragmentation and occurs mostly in Echinoderms.
  • When a part of an organism, like an arm, detaches from the parent body, it grows into a completely new individual. 
• Parthenogenesis-
  • This is a form of asexual reproduction where the egg develops without fertilization.
  • This process occurs in bees, wasps, ants, aphids, rotifers, etc. Ants, wasps, and bees produce haploid males. Parthenogenesis has been observed in a few vertebrates such as hammerhead sharks, Komodo dragons, blacktop sharks when the females were isolated from the males.

In vitro fertilization (IVF) is a process by which an egg is fertilized by sperm outside the body: in-vitro. The process involves monitoring and stimulating a woman's ovulatory process, removing ovum or ova (egg or eggs) from the woman's ovaries and letting sperm fertilize them in a liquid in a laboratory. The fertilized egg (zygote) is cultured in a growth medium and is then implanted in the same or another woman's uterus, with the intention of establishing a successful pregnancy.

Resorcinol is used as an antiseptic and disinfectant in typical pharmaceutical products in the treatment of skin disorders and infections such as acne, seborrheic dermatitis, eczema, psoriasis, corns, calluses, and warts. It exerts a keratolytic activity. Resorcinol works by helping to remove hard, scaly, or roughened skin.

The dividing cells of the vascular cambium consist of long, narrow fusiform initials, from which the tracheary elements are derived, and ray initials, from which ray parenchyma is formed. The vascular cambium is composed of two kinds of cells, ray initials and fusiform initials.

The correct answer is: [Cr(NCS)₄(NH₃)₂]^- : Diamminetetrathiocyanatochromate(III) ion. Reinecke's salt is a chemical compound with the formula NH₄[Cr(NCS)₄(NH₃)₂]·H₂O. The dark-red crystalline compound is soluble in boiling water, acetone, and ethanol. The chromium atom is surrounded by six nitrogen atoms in an octahedral geometry. The NH₃ ligands are mutually trans and the Cr–NCS groups are linear. The salt crystallizes with one molecule of water.