Evolution and Human Origins: A Comprehensive Study
Evolution: Key Concepts and Evidence
Neutral Theory of Molecular Evolution
Independent: The Japanese scientist Motoo Kimura suggested that most mutations that occur during evolution are neutral, indifferent to natural selection. For the same reason, their distribution in a population corresponds to a purely random factor. According to the neutral theory, natural selection is not pure chance but allows for several populations in which a particular mutated gene can be dispersed without any selective
Read MoreDNA Structure, Function, and Genetic Code
DNA: Structure and Characteristics
1) DNA is composed of two chains coiled together to form a double helix.
2) Each chain is made up of units called nucleotides. In DNA, there are four types of nucleotides: Adenine (A), Guanine (G), Cytosine (C), and Thymine (T). Each nucleotide consists of a phosphate, a deoxyribose sugar, and a nitrogenous base.
3) The two chains are united through their nucleotides in the following way: adenine binds to thymine (A-T), and guanine binds to cytosine (G-C). The number
Read MoreCellular Energy: Mitochondria and Metabolism
Mitochondria: The Powerhouses of the Cell
Mitochondria are cellular organelles responsible for supplying most of the energy necessary for cell activity. They act as central powerhouses of the cell and synthesize ATP at the expense of metabolic fuels. In the mitochondrial matrix are located enzymes responsible for fatty acid oxidation, amino acids, pyruvic acid, and the citric acid cycle.
Metabolism: Transforming Biomolecules
Metabolism is the set of chemical reactions that occur inside cells and cause
Read MoreBiotechnology: Applications, Benefits, and Risks
Biotechnology is technology based on biology, especially used in agriculture, pharmacy, food science, the environment, and medicine. It develops into a multidisciplinary approach involving various disciplines and sciences such as biology, biochemistry, genetics, virology, agronomy, engineering, physics, chemistry, medicine, veterinary medicine, and others. It has a great impact on pharmacy, medicine, microbiology, food science, mining, and agriculture, among other fields. Under the Convention on
Read MoreHuman Respiration and the Circulatory System
Respiration
Respiration is the process by which air containing oxygen enters our body, and air rich in carbon dioxide is expelled. A living being can survive for several hours without eating, sleeping, or drinking water, but cannot stop breathing for more than three minutes. This fact highlights the importance of breathing for our lives.
Composition of Air
- Nitrogen (N2): 78.084%
- Oxygen (O2): 20.946%
- Argon (Ar): 0.9340%
- Carbon dioxide (CO2): 0.039%
- Neon (Ne): 0.001818%
- Helium (He): 0.000524%
- Inter alia
Respiratory
Read MoreMendelian Genetics: Inheritance and Genetic Variation
Mendelian Genetics: Understanding Heredity
Genetics is the branch of biology that studies heredity and the mechanisms by which biological traits are transmitted from generation to generation.
- Gene: A segment of DNA that contains the information for the synthesis of a protein. This term was first used by Johannsen.
- Allele: Each of the different forms that a gene can have. Alleles arise from mutations.
- Locus: The specific location of a gene on a chromosome. A chromosome contains many loci.
- Genotype: The