Biology MCQs

Notes:
A method for the delivery of nucleic acids to cells by high-speed particle bombardment is called Biolistics.

Notes:
Glycolysis, part of cellular respiration, is a series of reactions that constitute the first phase of most carbohydrate catabolism, catabolism meaning the breaking down of larger molecules into smaller ones. Glycolysis breaks down glucose and forms pyruvate with the production of two molecules of ATP. The entire process from conversion of glucose to pyruvate is anaerobic that is it does not take place in presence of oxygen.

Notes:
The Iodine test is used to test for the presence of starch. Iodine solution– here iodine dissolved in an aqueous solution of potassium iodide and reacts with the starch producing a purple black color.

Notes:
An accessory fruit (sometimes called false fruit, spurious fruit, pseudo-fruit, or pseudo-carp) is a fruit in which some of the flesh is derived not from the ovary but from some adjacent tissue exterior to the carpel. Examples of accessory tissue are the receptacle of strawberries, figs, or mulberries, and the calyx of Gaultheria procumbens or Syzygium jambos. Pomes, such as apples and pears, are also accessory fruits, with much of the fruit flesh derived from a hypanthium.

Notes:
A humming bird the smallest of all known birds can rotate each of its wings in a circle, allowing them to be the only bird which can fly forwards, backwards, up, down, sideways or sit in sheer space. To hover, humming birds move their wings forward and backward in a repeated figure eight.

Notes:
The phosphate groups on DNA are ionic and charged. Each phosphate group on the DNA backbone has one unit of negative charge (-1). Charged molecules attract water and are hydrophilic. DNA has two hydrophilic polar external backbones made of sugars and phosphate groups joined by ester bonds. Therefore, DNA as nucleic acid is characterized by presence of phosphodiester bond.

Notes:
A Barr body is the inactive X chromosome in a female somatic cell in those species in which sex is determined by the presence of the Y or W chromosome rather than the diploidy of the X or Z. A typical human female has only one Barr body per somatic cell, while a typical human male has none.

Notes:
In an autosomal dominant disorder, the mutated gene is a dominant gene located on one of the nonsex chromosomes (autosomes). The early-onset form of Alzheimer disease is inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. In most cases, an affected person inherits the altered gene from one affected parent.

Notes:
Vitamin B12 is a water soluble compound containing cobalt. It cooperates with folic acid (folate) in the synthesis of deoxyribonucleic acid (DNA). A deficiency of either compound leads to disordered production of DNA and, hence, to the impaired production of red blood cells.

Notes:
Parietal cells (also known as oxyntic cells), are the epithelial cells that secrete hydrochloric acid (HCl) and intrinsic factor. These cells are located in the gastric glands found in the stomach. They contain an extensive secretory network from which the HCl is secreted by active transport into the stomach.