The discovery of the cell was possible do to the invention of the Microscope.
Answer:
a) Homozygous
Explanation:
An organism in which the two copies of the gene are identical is called homozygous in that gene. An organism with two different alleles of the genes is called heterozygous.
Answer:
1) c. five
2) a. lysine and arginine
3) g. two
4) d. four
Explanation:
A nucleotide can be defined as an organic molecule which forms the building block of nucleic acid such as deoxyribonucleic acid (DNA) and ribonucleic acid (RNA).
Basically, nucleotide comprises of the following parts;
1. Nitrogenous base: this includes adenine (A), thymine (T), guanine (G), and cytosine (C) which are mainly found in the DNA while adenine (A), guanine (G), uracil (U) and cytosine (C) are found in the RNA.
2. A phosphate group.
3. A penrose sugar: it is either deoxyribose in DNA or ribose in RNA.
The two parts or chemical components of a nucleotide which do not change throughout the structure of DNA are;
I. Five-Carbon Sugar also known as deoxyribose and it has hydrogen on its second carbon.
II. Phosphate: this is the structural backbone that provides support to DNA.
Histones are a group of highly basic proteins that are mainly associated with deoxyribonucleic acid (DNA) in the nucleus of a living organism and then condense it to chromatin.
Histones include five main classes of relatively small basic proteins containing relatively large amounts of lysine and arginine. Nucleosomes are made of two each of four types of histones.
B) Diploid - Only Gametes are Haploid. Every other cells are somatic cells which are diploid. They contain 46 chromosomes rather than 23 that the haploid carry. Neurons and glial cells make up of the brain and that makes up the nervous tissue. Just remember Gametes (sex cells) are the only cells that are haploids.