Railway Science (Biology – Miscellaneous) (Part-III)

Mendel’s laws of inheritance, including the law of segregation and the law of independent assortment, are based on his experiments with pea plants that were pure-breeding, meaning they consistently produced offspring with the same traits as the parent.

Somatic mutation: A genetic alteration that occurs within the cells of an organism's body, except for the reproductive cells (sperm and egg cells). Deletion mutation: A type of genetic alteration that involves the loss or removal of one or more nucleotides (the building blocks of DNA) from a DNA sequence.
Insertion mutation: A type of genetic alteration that involves the addition of one or more nucleotides into a DNA sequence.
Duplication mutation: A type of genetic mutation that involves the replication or copying of a segment of DNA within a chromosome.

Regeneration: if the individual is somehow cut or broken up into many pieces, many of these pieces grow into separate individuals. For example - Hydra and Planaria. For unicellular organisms, cell division, or fission, leads to the creation of new individuals.

The plant vascular system helps to deliver various resources to the different plant organs and provides mechanical support.
Respiratory - The important system in the plant/human body, the place where gas exchange happens. Examples - Lungs, Pharynx, Larynx, Trachea and Bronchi.
Nervous system - It is responsible for the control of the body and consists of the Brain, Spinal cord, Sensory organs, and all of the nerves that connect these organs with the rest of the body.
Excretory system - The bodily process of discharging wastes. Examples - Kidneys, Large Intestine, Liver, Skin and Lungs.

Species is a group of individuals that share similar characteristics and can interbreed to produce fertile offspring. Kingdom - A high-level taxonomic rank used to categorize organisms into broad groups.
Most widely recognized kingdoms - Animalia, Plantae, Fungi, Protista, and Monera. Genus - A taxonomic rank lower than family and higher than species. Family is the rank in between order and genus. Example - Panthera (lions, tigers, etc.) and Felis (domestic cats).

A sheep named Dolly was the first mammal to be cloned by Ian Wilmut and his colleagues at the Roslin Institute in Scotland. Fertilization is the process of fusion of male and female sex cells (gametes).
Regeneration is the process of restoring damaged or missing cells, tissues, organs and even entire body parts to full function in plants and animals.
IVF (In vitro fertilization) involves retrieving eggs from ovaries and manually combining them with sperm

Areolar connective tissue is found between the skin and muscles, around blood vessels and nerves and in the bone marrow. It fills the spaces between the different organs, and supports internal organs and helps in repair of tissues.

Analogous organs: These are organs in different organisms that have similar functions but different evolutionary origins. For example, the wings of birds and bats are analogous but not homologous. Fossil: This is the preserved remains or imprints of organisms from past geological ages.

analogous organs: Its examples include the wings of insects and birds, both serving the function of flight but having completely different underlying structures.

Enamel is the hardest substance in the body. It is the hard chewing surface of the teeth that helps in the mastication of food. It does not dissolve in water, but is corroded when the pH in the mouth is below 5.5.
It is arranged in a crystal structure known as hydroxyapatite. Fluoride deficiency in drinking water is harmful to man and causes diseases such as tooth decay.