Genetics c1

• Genetics is coined by William Bateson
• Genetics is derived from the Greek word gen meaning to become or to grow into something
• Genetics is a branch of biology that deals with the principles of heredity and variation
• Heredity is the transmission of the genes from parents to offspring from generation to generation through the process of reproduction
• Heredity is the tendency of the offspring to resemble their parents
• variation is the differences of individuals belonging in the same population or species
• Variation is the tendency of the offspring to vary from their parents
• Types of variations: Morphological or structural, Physiological, Behavioral, and Sexual
• Morphological Variation is the differences in body forms and structures such as facial shape, body length, color, etc.
• Physiological variation refers to the differences in physical functions like metabolism, blood pressure, heart rate, etc.
• Sexual variation refers to the differences between males and females in terms of appearance, physiology, and behavior
• Behavioral variation refers to the differences in behavior patterns such as aggression, shyness, friendliness, etc.
• Behavioral variation refers to the differences in how organisms behave towards other members of its own kind
• Behavioral Variation in individual animals behave differently from each other for myriad interrelated intrinsic and extrinsic reasons
• Behavioral Variation: the ability to learn, feeding, mating, and parental care
• Sexual variation is also known as sexual dimorphism, which is the difference in size, shape, and color between the sexes
• Causes of VAriation: 1. Genetic 2. Environment 3. Interaction between Genetics and Environment
• Genotype - genetic composition and the genes inherited
• Within Individual: Meiosis, Mutation, Gamete Combination
• Meiosis: a type of cell division that results in four daughter cells each with half the number of chromosomes of the parent cell, as in the production of gametes and plant spores
• Independent assortment - the random arrangement of chromosomes during meiosis
• Crossing over - the exchange of genetic material between homologous chromosomes
• Mutation is the changes in genetic materials
• gamete combination: sperm + egg = zygote
• Gamete combination is the random joining of sperm and egg cells to form a zygote at fertilisation
• Gene flow is the movement of alleles from one population to another.
• Within population: Gene flow, Natural Selection, Random Genetic drift
• Immigration: the possible introduction of alleles from a new population into a population of organisms
• Emmigration: the possible loss of alleles from a population due to the movement of individuals
• Random Genetic drift: changes occur by chance
• Natural Selection: The process by which individuals with traits that are better suited to their environment survive and reproduce more than individuals with traits that are less suited
• Natural Selection - some variations provide individuals with increased chance of survival
• Environment is the condition in which they have been developed
• Two individuals who are genetically identical can be phenotypically different due to differences in environment.
• Environmental factors may include temperature, food, light, and other external factors
• Interaction between the genetics and environment is the combination of genes and environment
• Field of Genetics: Transmission genetics, Molecular genetics, Population genetics, quantitative genetics, and Cytogenetics
• Transmission Genetics is the transmission of genes from generation to generation
• Molecular Genetics is the structure and function of genes at the molecular level. it is the nature of genes, how they are replicated, regulated, and expressed.
• Population Genetics is the distribution and behavior of genes within and between the population.