Biology Test - 65

If two alleles of a given gene are identical, the organism is called a homozygote and is said to be homozygous with respect to that gene; if instead, the two alleles are different, the organism is a heterozygote and is heterozygous.

Chromosomes: Carriers of Genetic Material Each species has a unique set of chromosomes which are the carriers of genetic information. mitosis One cell gives rise to two genetically identical daughter cells during the process of mitosis.

Metacentric. These are X-shaped chromosomes, with the centromere in the middle so that the two arms of the chromosomes are almost equal. A chromosome is metacentric if its two arms are roughly equal in length.

Allele frequencies in a population may change due to gene flow, genetic drift, natural selection and mutation. These are referred to as the four fundamental forces of evolution.

Twenty third pair of human chromosomes is called sex chromosomes (XY in males and XX in females). These chromosomes of dissimilar appearance that determine sex in some diploid organisms are known as Heterosomes.

Wilhelm Roux in 1883 speculated that chromosomes are the carriers of inheritance. Danish botanist Wilhelm Johannsen coined the word "gene" ("gen" in Danish and German) in 1909 to describe these fundamental physical and functional units of heredity. William Bateson in 1905 coined the term genetics from the word gene.

From the alveoli, the oxygen from the air you breathe enters your blood in nearby blood vessels. This is a process called oxygen diffusion. Once your blood is oxygenated, it carries oxygen throughout your body. Another form of diffusion occurs when blood containing carbon dioxide travels back to your lungs.

There are three pairs of submetacentric autosomes and 33 pairs of acrocentric autosomal chromosomes in camelids. The X chromosome is the largest submetacentric chromosome, and the Y chromosome is a very small acrocentric chromosome.

Nutrients which are required by plants in very small amounts are termed as Micro Elements or macronutrients. Some of them include boron , copper, manganese, iron, chlorine, and molybdenum. Nutrients which are required by plants in larger amounts are termed as Macronutrients.

Autosomes are homologous chromosomes i.e. chromosomes which contain the same genes (regions of DNA) in the same order along their chromosomal arms. The chromosomes of the 23rd pair are called allosomes consisting of two X chromosomes in most females, and an X chromosome and a Y chromosome in most males.