Mendelian 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
Angiosperms: Characteristics, Evolution, and Classification
Angiosperms is the common name of the division or phylum that contains flowering plants, which are the dominant form of plant life. The members of this division are the source of most of the food on which humans and other mammals base their livelihood, as well as many raw materials and natural products. This includes almost all shrubs and herbaceous plants, most trees except pines and other conifers, and more specialized plants, like succulents, epiphytes, and aquatic plants. Although there are
Read MoreCell Membrane Structure, Function, and Transport Mechanisms
The Plasma Membrane
The plasma membrane is a biological membrane that separates the interior of a cell from the extracellular environment. It allows interactions and is selective.
Composition
- Lipids: These are amphipathic molecules. The main ones are phospholipids (which have hydrophobic tails and polar heads), cholesterol (found only in animals, interspersed between phospholipids), and glycolipids (occurring in the outer monolayer; in plants, they appear more often).
- Proteins: These fulfill the biological
Mendel’s Laws and Genetic Mutations: Inheritance Principles
Mendel’s First Law: Law of Uniformity
Mendel’s first law, the law of uniformity, concerns the first filial generation. The offspring resulting from crossing two pure strains (homozygous) forms a group of hybrids that have uniformity, both in terms of genotype and phenotype. This law is based on the crossing of two varieties homozygous for a character (homozygous dominant and homozygous recessive, AA and aa), which gives rise to a uniform F1 generation (Aa), with the same phenotype as the dominant
Read MoreUnderstanding Health, Disease, and Medical Practices
Defining Health and Disease
According to the World Health Organization, health is defined as:
- A state of complete physical, mental, and social well-being and not merely the absence of disease or infirmity.
Disease can be defined as an altered state of being, i.e., temporary or permanent loss of:
- Homeostasis
Quality of life depends on:
- Physical health
- Mental health
- Level of autonomy
- Social relationships and their environment
- Life expectancy
Genetics and Environmental Factors
The genotype is:
- The genetic information
Puberty and Human Reproductive Health: Changes and Processes
What is Puberty?
Puberty is a period in a person’s life when significant changes occur. These changes are both physical and psychological, affecting appearance, body function, personality, and relationships with others. It typically begins around the ages of 10 or 11, but the exact age varies for each individual.
Physical Changes During Puberty
In Boys:
- Growth of pubic hair, beard, mustache, and body hair
- Widening of shoulders and chest
- Increased muscle mass
- Voice change
- Growth of penis and testicles
- Beginning