Chapter 11 : specific features of meiosis

Meiosis has three unique features : The mechanism of cell division varies in important details in different organism. This is particularly true of chromosomal separation mechanism, which differ substantially in protists and fungi from the process in plants and animals that we will describe here. Meiosis in a diploid organism consists of two rounds of […]

Chapter 10 : meiosis

The sequence of events during meiosis involves two nuclear divisions ( meiosis I and meiosis II ). Prophase 1 In prophase 1 of meiosis, the DNA coils tighter, and individual chromosomes first become visible under the light microscope as a matrix of fine threads. Because the DNA has already replicated before the onset of meiosis, […]

Chapter 9 : Replication

 1) Definition The DNA replication is one of the key mechanisms of  cell cycle. It is a highly regulated biological process in which new synthesis and  repair mechanisms ensure the integrity of the genome. S phase or replication phase follows the G1 phase during which the cell synthesizes all the elements necessary for this replication. […]

Chapter 7 : Photosynthesis

                                 Photosynthesis Photosynthesis is the process that converts solar energy to chemical energy. Directly or indirectly, photosynthesis nourishes almost the entire living worlds -Autotrophs sustain themselves without eating anything derived from other organisms -Autotrophs are the producers of the biosphere, producing […]

Chapter 6 : cellular energy production

                                        AEROBIC WAY The citric acid cycle completes the energy yielding oxidation of organic molecules. In the presence of O2, pyruvate enters the mitochondrion. Before the citric acid cycle can begin, pyruvate must be converted to […]

Chapter 5 : bioenergetics

                         Introduction to bioenergetics Cellular respiration is composed of three topics: Redox reactions (oxidation-reduction) Electron transport chain Glycolysis In fact living cells require energy from outside sources. Some animals obtain energy by eating plants and some others feed on other organisms that eat plants, and […]

Chapter 4: enzyme substrate complex

Substrate specificity of enzymes -The reaction that an enzyme acts on is called the enzyme’s substrate. -The enzyme binds to its substrate forming an enzyme-substrate complex -The active site is the region on the enzyme where the substrate binds. -Induced fit of a substrate brings chemical groups of the active site into positions that enhance […]

Chapter 3 : cellular metabolism

                                            Cellular metabolism –          Metabolic path ways –          Thermodynamics –          Free energy –          Introduction to enzymes Overview: the energy of life The living cell is a miniature chemical factory where thousands of reactions occur.The […]

Chapter 2 : Microbial genetics and evolution

Microbiology is the study of single celled creatures or organisms. They are divided in ,Eukaryotes and Prokaryotes Eukaryotes  : Fungi ,Protozoa Prokaryotes : Bacteria,Archie Because bacteria are most diverse collection of organisms, it is very hard to say something universally about bacteria. So, this discussion can be inexact concerning all bacteria. Generally, bacteria are small microorganismes (eg: E […]