General Science Questions (MCQs) for Competitive Examinations

Notes:
In most fish, the heart consists of four parts, including two chambers and an entrance and exit. The first part is the sinus venosus, a thin-walled sac that accumulates blood from the fish’s veins before permitting it to flow to the second part, the atrium. The atrium is a large muscular chamber, present as a one-way passage, that sends blood to the third part, the ventricles. The ventricle is a thick-walled, muscular chamber that pumps the blood, first to the fourth part, bulbus arteriosus. The bulbus arteriosus is a large tube, and then out of the heart, which attaches to the aorta, through which blood flows to the gills for oxygenation.

Notes:
Ornithology is a branch of zoology that deals with the study of birds. The science of ornithology has developed several key concepts in evolution, behaviour and ecology such as the definition of species, the process of speciation, instinct, learning, ecological niches, guilds, island biogeography, phylogeography and conservation.

Notes:
Bariatric surgical procedures cause weight loss by restricting the amount of food the stomach can hold, causing malabsorption of nutrients, or by a combination of both gastric restriction and malabsorption. The most common bariatric surgery procedures are gastric bypass, sleeve gastrectomy, adjustable gastric band, and biliopancreatic diversion with duodenal switch. Gastric bypass and other weight-loss surgeries make changes to digestive system.

Notes:
Mostly medicinal herbs grown from 30 to 90 cm in height. They reach up to 30 cm in diameter.

Notes:
Lysosomes are membrane-enclosed organelles that are known as suicidal bags of the cell. They contain digestive enzymes, and break down food, cellular debris and foreign invaders like bacteria. In the event that the cell is injured beyond repair, or becomes old, the lysosome digests the cell, hence the name ‘suicide bag of the cell’.

Notes:
Buccal cavity (oral cavity) refers to the mouth cavity: the beginning of the alimentary canal, which leads to the pharynx and (in vertebrates) to the oesophagus. It is part of the digestive system. In mammals it contains the tongue and teeth, which assist in the mechanical breakdown of food, and the openings of the salivary glands.

Notes:
DNA does not directly control the formation of a polypeptide. However, it forms an intermediate template mRNA molecule, which directs the synthesis of polypeptide. The DNA can be compared to a master copy that is carefully preserved in the nucleus and used for preparing working copies in the form of mRNA molecules.

Notes:
The deficiency of magnesium leads to yellowish green blotch near the base of the leaf between the midrib and the outer edge (chlorosis). The yellow area enlarges until the only green remaining is at the tip and base of the leaf as an inverted V-shaped area on the midrib.

Notes:
The arteries (red) carry oxygen and nutrients away from your heart, to your body’s tissues. The veins (blue) take oxygen-poor blood back to theheart. Arteries begin with the aorta, the large artery leaving the heart. They carry oxygen-rich blood away from the heart to all of the body’s tissues.

Notes:
Ornithophily refers to the pollination of flowering plants by birds. Birds involved in ornithophily tend to be specialist nectarivores with brushy tongues and long bills, that are either capable of hovering flight or light enough to perch on the flower structures.