General Science Questions (MCQs) for Competitive Examinations

Notes:
Capra Hircus is the scientific name of domestic goat or simply goat. It is a subspecies of C. aegagrus domesticated from the wild goat of southwest Asia and Eastern Europe. The goat is a member of the animal family Bovidae and is closely related to the sheep; both are placed in the goat-antelope subfamily Caprinae.

Notes:
Sex determination in human beings depends on the particular pair of sex chromosomes an individual inherits. The homogametic sex, females, usually possess two identical sex chromosomes (XX). On the other hand, males, who are the heterogametic sex, typically present a pair of different sex chromosomes (XY). This distinct pair forms the blueprint that directs male physical and biological characteristics development.

Notes:
Red Blood Corpuscles (RBCs) do not contain mitochondria when matured. These are the site of aerobic respiration. They they also lack the oxidative enzymes that are required for aerobic respiration. For this reason, Embden-Meyerhof pathway is used to process glucose and thus obtain energy. This is an anaerobic energy producing process that has been shown to use glycogen in the absence of glucose.

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Pyria, or periodontal disease, is a progressive gum disease characterized by inflammation resulting from the toxins found in plaque. It leads to bleeding of the gums. If allowed to progress, Pyria begins to destroy underlying tissue, which may eventually lead to premature tooth loss.

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Eutrophication is the ecosystem response to the addition of artificial or natural substances, such as nitrates and phosphates, through fertilizers or sewage. It leads not only to increased levels of nutrients, but increased Biological Oxygen Demand as well following the decay of algal bloom in stagnant water reservoirs.

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All verteberates have notochord, body cavity and gills in their embryonic stage or adult stage but not have haemocoel. It’s presence is well marked in the members of phylum in Arthopoda.

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Pleiotropy describes the genetic effect of a single gene on multiple phenotypic traits. The underlying mechanism is that the gene codes for a product that is, for example, used by various cells, or has a signaling function on various targets. A classic example of pleiotropy is phenylketonuria, a human disease that affects multiple systems but is caused by one gene defect.

Notes:
• Green revolution- Crop production
• Golden revolution- Honey /Tomato production.
• Blue revolution- Fish production
• Silver revolution- Egg production
• White revolution Milk production or Operation flood

Notes:
The loose union of structure of the same whorl is called cohesion, but the intimate histological union is called connation. When anthers are fused with each other, the condition is described as syngenesious e.g., Compositae, Lobeliaceae. This fusion is called cohesion. When there is fusion of stamens with petals, they are described as epipetalous e.g., Gamopetale.

Notes:
In the nucleus of each cell, the DNA molecule is packaged into thread-like structures called chromosomes. Each chromosome is made up of DNA tightly coiled many times around proteins called histones that support its structure.