Biology Questions

A vitamin is an organic molecule that is an essential micronutrient that an organism needs in small quantities for the proper functioning of its metabolism.

There are 13 essential vitamins that our body need. They are categorized into 

1. Water soluble

2. Fat soluble

Water-soluble vitamins dissolve in water, which means these vitamins and nutrients dissolve quickly in the body. Unlike fat-soluble vitamins, water-soluble vitamins are carried to the body’s tissues, but the body cannot store them.

Water-soluble vitamins are Vitamin B1, B2, B3, B5, B12, B6, B7 & B9 and Vitamin C.

Fat-soluble vitamins are soluble in fats. They are absorbed by fat globules that travel through the small intestines and into the general blood circulation within the body. Unlike water-soluble vitamins, fat-soluble vitamins are stored in the body when they are not in use.

Fat-soluble vitamins are - Vitamin A, D, E and K.

The Bacteria that causes Food Borne illness are called Food Borne Pathogens. Most of the pathogens are mesophilic in nature, optimum temperature may be around 20-45 degree celsius. This range of temperatures is often called the "Danger Zone." Dry foods do not support the growth of bacteria.

In order to kill pathogenic bacteria you need temperatures above 74ºC. Temperature is the easiest factor to control in order to prevent bacterial growth.

The number of cell layers and cell types together give rise to 6 different types of epithelial tissue.

1. Simple squamous epithelia

2. Simple cuboidal epithelia

3. Simple columnar epithelia

4. Stratified squamous epithelia

5. Stratified cuboidal epithelia

6. Stratified columnar epithelia

Stratified squamous epithelia is best suited for areas subject to friction.

Genes which are segment of DNA of a cell contains instructions for assembling proteins.

The fimbriae of the uterine tube, also known as fimbriae tubae, are small, fingerlike projections at the end of the fallopian tubes, through which eggs move from the ovaries to the uterus.

The fimbriae are connected to the ovary.

Random mutations are the ultimate source of genetic variation. Mutations are likely to be rare and most mutations are neutral or deleterious, but in some instances, the new alleles can be favored by natural selection. Polyploidy is an example of chromosomal mutation.

Mutations are changes in the DNA. A single mutation can have a large effect.

1) mutation - an alteration in DNA sequence, various types

2) intragenic recombination - results in entirely new associations of genes not present in either parental genome.

Two forms of intragenic recombination:

a) crossing over
b) independent assortment
3) reticulation – acquisition of genetic material from unrelated or relatively unrelated sources (e.g., hybrid species, horizontal gene transfer).