Foundations of Evolutionary Thought
Early Ideas on Species Change
Pierre-Louis Moreau de Maupertuis (1698-1759) suggested that the multiplication of species resulted from accidental recombination of particles from both parents, leading to offspring with varied traits from both parents.
Georges-Louis Leclerc, Comte de Buffon (1707-1788) proposed that animals had not been created as they appeared; rather, modern forms modified from common ancestors. Species change over time.
Jean-Baptiste Lamarck (1744-1829)
Lamarck believed animals possessed
Read MoreFundamentals of Taxonomy, Phylogeny, and Population Evolution
Basic Taxonomy and Phylogeny
Basic taxonomy has its roots in Aristotle’s original 2 Kingdom system. Since that time, modern taxonomy has undergone countless revisions, including important contributions by Linnaeus, Whittaker, Woese (Table 24.2), and others. Be able to recognize and express important historical changes to our taxonomical schemes.
In biology today, modern taxonomy is synonymous with phylogenetic systematics. Understand the basic principles of grouping organisms based on evolutionary
Read MoreFundamentals of Genetics, Heredity, and Human Ecology
Nucleotide Base Pairing in DNA
In DNA, the nucleotide bases pair specifically: Adenine (A) pairs with Thymine (T), and Guanine (G) pairs with Cytosine (C).
What Makes Individuals Unique?
Individuals are unique primarily due to variations in their alleles, which are different versions of the same gene.
Autosomes vs. Sex Chromosomes
Humans typically have 22 pairs of autosomes (homologous chromosomes that are not sex chromosomes) and one pair of sex chromosomes (XX for females, XY for males), totaling 46
Cadaveric Lividity and Rigor Mortis: A Forensic Analysis
Cadaveric Lividity
Cadaveric lividity depends on the position of the cadaver. When the body is supine (face up), the spots form on the entire dorsal surface, except where pressure is applied. If the body is prone (face down), the lividity appears on the front of the body, respecting pressure areas. As a rule, lividity is located in the dependent regions of the body, indicating the position in which the body remained.
Varieties of Lividity
Hypostatic purple lividity consists of point-like scarlet fever.
Read MoreUnderstanding Genes, Alleles, and Mendelian Genetics
A gene is a fragment of DNA that contains the information needed to make a protein. Qualitative characters are determined by a single gene, while quantitative characters are influenced by many genes.
Alleles, Genotypes, and Phenotypes
Alleles are different versions of the same gene within a population. An individual is homozygous for a specific gene if they have two identical alleles on their homologous chromosomes. They are heterozygous if they possess two different alleles for that gene.
- Genotype:
Understanding Cells: Anatomy, Function, and Division
Cell Structure and Function
A cell is the smallest functional and anatomical unit of living beings. Some organisms consist of a single cell (unicellular), while others have multiple cells (multicellular). Cells perform the following vital functions:
- Nutrition: Taking in molecules from the environment and transforming them into energy.
- Relationship: Communicating with the external environment.
- Reproduction: Forming new cells from existing ones, with the same genetic information.
The cell theory, developed
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