Biomolecules, Genetics, and Ecology Essentials

Anabolic Reactions & Biomolecules

A reaction where two molecules join is anabolic and produces NH₂. Glucose and starch are carbohydrates (CH). Glucose + fructose = sucrose. Unsaturated fats increase HDL levels. An amino acid has an H and R group bonded to a carbon atom, along with NH₂ and COOH. Adenine, cytosine, guanine (thymine in DNA and uracil in RNA). Saponifiable lipids include phospholipids, fats, and waxes.

Factors Affecting Enzyme Activity

• Temperature
• pH levels
• Substrate concentration

Four Main Biomolecule Groups

Carbohydrates, lipids, proteins, and nucleic acids.

Cell Biology Concepts

Schleiden. Kingdoms with cells containing mitochondria: Animalia, Plantae, Fungi, and Protoctista. Organelles of endosymbiotic origin: mitochondria and chloroplasts. Mitochondria perform aerobic cellular respiration. Nonsaponifiable lipids: steroids and terpenes. tRNA carries amino acids to the ribosomes.

Genetics Terminology

• Homozygous: Two alleles of the same type.
• Alleles: Different versions of a gene.
• Phenotype: The expression of an organism's genotype.
• Linked genes: Genes located on the same chromosome.

Darwinism and Evolution

Requirements for evolution according to Darwinism: diversity among individuals, scarcity of resources (struggle for survival), and natural selection of the fittest.

Ecological Definitions

• Community: A group of populations in an ecosystem.
• Ecological niche: The role played by a species.
• Population: A group of organisms from the same species.
• Habitat: The environment in which a species lives.

Autotrophs vs. Heterotrophs

Autotrophs synthesize their own molecules from simple inorganic substances (sunlight - photosynthesis, or oxidation of molecules). Heterotrophs obtain their organic molecules from other organisms. Nitrogen-fixing bacteria, nitrifying bacteria, and denitrifying bacteria.

Endosymbiotic Theory

The endosymbiotic theory states that some organelles in eukaryotic cells were once prokaryotic microbes. Mitochondria and chloroplasts are the same size as prokaryotic cells and divide by binary fission. Mitochondria and chloroplasts have their own circular DNA.

Cellular Actions and DNA Replication

Every single cell that forms a multicellular organism carries out its own actions, although there is a certain amount of coordination between them.

Replication Steps

1. Denaturation: DNA is heated to 95°C to break hydrogen bonds and separate the two strands.
2. Annealing: The temperature is cooled to 55°C.
3. Elongation: The temperature is increased to 72°C, encouraging Taq DNA polymerase to replicate both strands, starting at the primer, producing two double-stranded copies of the original DNA.