Animal breeding and Genetics. Instructor: Dr. Jihad Abdallah Lecture 1 Cells and chromosomes. Animal Cell. Cell Boundaries. Plasma Membrane: An outer covering that defines the cell boundary
Animal breeding and Genetics
Instructor: Dr. Jihad Abdallah
Cells and chromosomes
- Nuclear membrane with nuclear pores
- Nucleolus: site for synthesis of ribosomal RNA (rRNA).
- Tubulin-derived microtubules
- Actin-derived microfilaments
1. Smooth ER: serve as the site for the synthesis of fatty acids and phospholipids
2. Rough ER: studded with “ribosomes” which serve as sites for the translation of mRNA into proteins.
- Are the sites of oxidative phases of cell respiration chemical reactions generate large amounts of ATP
- Contain a type of DNA distinct from that in the nucleus
- Can duplicate themselves and transcribe and translate their own genetic information
- p arm (short arm) above the centromere
- q arm (long arm) below the centromere
The chromatin material just before cell division forms into chromosomes. Each chromosome is made up of two longitudinal strands called sister chromatids.
1) Sex and Autosomal chromosomes:
2) Chromosomes are classified based on the position of the centromere into:
3) Human chromosomes are classified based on size and shape into 8 groups:
Karyogram of a human male.
- Diploid: 2n (have two sets of chromosomes present in pairs and called homologous chromosomes like somatic cells of humans and animals)
- Polyploid (3n, 4n, ….,etc) more than two basic chromosome sets like some plants
- Triploid: (3n)
- Tetraploid: (4n)
- Pentaploid: (5n)
- Hexaploid: (6n)
Chromosome numbers (2n) in some animals and insects