Basic genetics and biochemistry of inheritance

Genetics

• heredity

• variation

• traits

• conditions

Chromosomes

consists of long DNA molecule that is folded around protein

Joined together

each unit of chromosomes consists of two rod-like structures ________ at a constricted point

Chromatin

DNA and chromosome proteins are called

Centromere

the region of chromosome where chromatids are held together

Telocentric

Acrocentric

Meta centric

Chromosomes are classified with respect to the location of centromere

Karyotype

• known as an arrangement that provides a picture of the complete set of chromosomes

• is useful in determining the chromosome number of a species

Homologous chromosomes

contains DNA that codes for the same genes

Loci

the position or location on a chromosome where a particular gene is found

Alleles

are different forms of the gene that can be found on the same loci

• genes are different

• occupies same position in the chromosome

• have defects on same trait

Mitosis

increase in the number of cells from a single-celled zygote that contains the exact same set of chromosomes as the original single-celled zygote

Meiosis

produces four haploid cells after the process, each with own genetic composition which is different from the diploid mother cell

Gametes

Spores

the product of meiotic division

Y chromosome

• contains SRY gene

• provides the initial signal for differentiation of the gonads in the embryo to develop into a testis rather than an ovary

Trisomy

term for an extra chromosome

Monosomy

term for lacking one chromosome

Euploidy

contains a complete diploid set of chromosomes

Aneuploidy

occurs when an organism loses or gains one or more chromosomes

Deoxyribonucleic acid

DNA

Nucleotides

called as each strand is a linear arrangement of repeating similar units

Adenine

Guanine

Purine bases of DNA

Thymine

Cytosine

Pyrimidine bases of DNA

Structural gene

a segment of DNA including all the nucleotides that are transcribed into mRNA

Replication

Begins with separation of the double helix. As strands unwind, nucleotides pair up with complementary bases

DNA polymerase

Synthesis is catalyzed by the enzyme called:

Transcription

the DNA sequence in one of the strands acts as a template for synthesis of RNA

RNA polymerase

synthesis is catalyzed