Biology: Introduction to Cell Biology change

Definition and Branches

• Biology: the scientific study of life and living organisms
• Branches:
  • Botany: study of plants
  • Zoology: study of animals
  • Microbiology: study of microorganisms
  • Ecology: study of interactions between organisms and their environment

Cell Biology

• Cell: basic structural and functional unit of life
  • Cell membrane: semi-permeable membrane surrounding the cell
  • Cytoplasm: jelly-like substance inside the cell membrane
  • Nucleus: control center of the cell where DNA is stored
  • Organelles: specialized structures within the cell (e.g. mitochondria, ribosomes)

Genetics

• DNA (Deoxyribonucleic acid): molecule containing genetic information
  • Double helix structure
  • Composed of nucleotides (A, C, G, T)
• Genes: sequences of DNA that encode proteins
  • Expression: process of creating a protein from a gene
  • Inheritance: passing of genetic traits from parents to offspring

Evolution

• Theory of Evolution: process of change in species over time
  • Mechanisms:
    • Mutation: change in DNA sequence
    • Genetic drift: random change in gene frequency
    • Natural selection: survival and reproduction of individuals with advantageous traits
  • Evidence:
    • Fossil record
    • Comparative anatomy and embryology
    • Molecular biology

Ecology

• Ecosystem: community of organisms and their environment
  • Energy flow: movement of energy through the ecosystem (producer, consumer, decomposer)
  • Nutrient cycling: recycling of nutrients (water, carbon, nitrogen)
  • Population dynamics: study of population growth and decline

Biological Molecules

• Carbohydrates: energy storage molecules (sugars, starches, cellulose)
• Proteins: structural and functional molecules (enzymes, hormones, structural proteins)
• Lipids: energy storage molecules (fats, oils)
• Nucleic acids: genetic material (DNA, RNA)

Biology

• Scientific study of life and living organisms
• Branches include Botany, Zoology, Microbiology, and Ecology

Cell Structure

Cell Membrane

• Semi-permeable membrane surrounding the cell

Cytoplasm

• Jelly-like substance inside the cell membrane

Nucleus

• Control center of the cell where DNA is stored

Organelles

• Specialized structures within the cell (e.g. mitochondria, ribosomes)

Genetics

DNA

• Molecule containing genetic information
• Double helix structure composed of nucleotides (A, C, G, T)

Genes

• Sequences of DNA that encode proteins
• Expression: process of creating a protein from a gene
• Inheritance: passing of genetic traits from parents to offspring

Evolution

Theory of Evolution

• Process of change in species over time

Mechanisms of Evolution

• Mutation: change in DNA sequence
• Genetic drift: random change in gene frequency
• Natural selection: survival and reproduction of individuals with advantageous traits

Evidence for Evolution

• Fossil record
• Comparative anatomy and embryology
• Molecular biology

Ecology

Ecosystem

• Community of organisms and their environment

Energy Flow

• Movement of energy through the ecosystem (producer, consumer, decomposer)

Nutrient Cycling

• Recycling of nutrients (water, carbon, nitrogen)

Population Dynamics

• Study of population growth and decline

Biological Molecules

Carbohydrates

• Energy storage molecules (sugars, starches, cellulose)

Proteins

• Structural and functional molecules (enzymes, hormones, structural proteins)

Lipids

• Energy storage molecules (fats, oils)

Nucleic Acids

• Genetic material (DNA, RNA)