Cell Biology Basics

Basic structural and functional units of life
Consist of:
- Cell membrane (plasma membrane)
- Cytoplasm
- Genetic material (DNA or RNA)
Types of cells:
- Prokaryotic cells (no true nucleus)
- Eukaryotic cells (true nucleus)

DNA (deoxyribonucleic acid): genetic material that stores information
RNA (ribonucleic acid): involved in protein synthesis and gene regulation
Genes: segments of DNA that code for specific traits
Chromosomes: thread-like structures that carry genes
Meiosis: process of cell division that results in gametes with unique genetic combinations

Change in species over time through natural selection and genetic drift
Mechanisms of evolution:
- Mutation
- Gene flow
- Genetic drift
- Natural selection
Evidence for evolution:
- Fossil record
- Comparative anatomy
- Molecular biology

Communities of organisms and their environment
Components of an ecosystem:
- Biotic factors (living organisms)
- Abiotic factors (non-living environment)
Energy flow:
- Producers (autotrophs)
- Consumers (heterotrophs)
- Decomposers

Cellular components: cell membrane, cytoplasm, and genetic material (DNA or RNA)
Cell membrane: regulates what enters and leaves the cell
Cytoplasm: jelly-like substance inside the cell membrane where metabolic processes occur
Genetic material: DNA or RNA that stores information for cellular functions

Mitochondria: generate energy through cellular respiration, converting glucose into ATP
Endoplasmic reticulum (ER): synthesizes and transports proteins
Ribosomes: site of protein synthesis, reads mRNA and builds polypeptide chains
Lysosomes: breaks down cellular waste and debris using digestive enzymes
Golgi apparatus: modifies, packages, and transports proteins and lipids

DNA: double-stranded helix, genetic material that stores information
RNA: single-stranded, involved in protein synthesis and gene regulation
Genes: segments of DNA that code for specific traits, passed from parents to offspring
Chromosomes: thread-like structures that carry genes, composed of DNA and proteins
Meiosis: process of cell division that results in gametes with unique genetic combinations

Definition: change in species over time through natural selection and genetic drift
Mechanisms of evolution:
- Mutation: changes in DNA sequence
- Gene flow: movement of genes between populations
- Genetic drift: random changes in gene frequency
- Natural selection: selection of traits that enhance survival and reproduction
Evidence for evolution:
- Fossil record: shows gradual changes in species over time
- Comparative anatomy: similarities and differences between body structures
- Molecular biology: similarities and differences between DNA and protein sequences

Definition: communities of organisms and their environment
Components of an ecosystem:
- Biotic factors: living organisms, including producers, consumers, and decomposers
- Abiotic factors: non-living environment, including temperature, light, and water
Energy flow:
- Producers: autotrophs that convert light energy into chemical energy
- Consumers: heterotrophs that obtain energy by consuming other organisms
- Decomposers: break down dead organic matter, releasing nutrients back into the environment

Carbohydrates: energy storage molecules, composed of carbon, hydrogen, and oxygen
Proteins: structural and functional molecules, composed of amino acids
Lipids: energy storage molecules, composed of fatty acids and glycerol
Nucleic acids: genetic material, composed of DNA and RNA

Photosynthesis: process of converting light energy into chemical energy, occurs in chloroplasts
Cellular respiration: process of generating energy from glucose, occurs in mitochondria
Fermentation: process of generating energy in the absence of oxygen, occurs in cytoplasm
Homeostasis: maintenance of a stable internal environment, regulation of temperature, pH, and other factors