Cell Biology and Genetics Overview

Cell Biology

• Cell Theory:

  • All living organisms are composed of cells.
  • The cell is the basic unit of life.
  • All cells arise from pre-existing cells.

• Cell Types:

  • Prokaryotic: No nucleus, smaller, simpler (e.g., bacteria).
  • Eukaryotic: Contains a nucleus, larger, complex (e.g., plant and animal cells).

• Cell Organelles:

  • Nucleus: Contains genetic material (DNA).
  • Mitochondria: Powerhouse of the cell, energy production.
  • Ribosomes: Protein synthesis.
  • Endoplasmic Reticulum: Protein (rough ER) and lipid synthesis (smooth ER).
  • Golgi Apparatus: Modifies and packages proteins.
  • Lysosomes: Digestion and waste removal.

Genetics

• DNA Structure:

  • Double helix, composed of nucleotides (A, T, C, G).

• Gene Expression:

  • Transcription: DNA to RNA in the nucleus.
  • Translation: RNA to protein in the cytoplasm.

• Mendelian Genetics:

  • Laws of Segregation and Independent Assortment.
  • Dominant and recessive alleles.

• Punnett Squares: Used to predict genetic variation in offspring.

Evolution

• Natural Selection:

  • Survival of the fittest; advantageous traits are passed on.

• Speciation:

  • Process by which new species arise.

• Evidence for Evolution:

  • Fossil records, comparative anatomy, molecular biology.

Ecology

• Ecosystems:

  • Composed of biotic (living) and abiotic (non-living) components.

• Food Chains and Webs:

  • Energy flow from producers (plants) to consumers (herbivores, carnivores).

• Biomes:

  • Major ecological areas (e.g., rainforest, desert, tundra).

• Population Dynamics:

  • Factors affecting population size: birth rate, death rate, immigration, emigration.

Human Biology

• Body Systems:

  • Circulatory: Transports blood and nutrients.
  • Respiratory: Gas exchange (O2 and CO2).
  • Digestive: Breaks down food for energy.
  • Nervous: Controls body functions, responds to stimuli.

• Homeostasis:

  • Maintenance of stable internal conditions (temperature, pH, etc.).

Biotechnology

• Genetic Engineering:

  • Modifying organisms’ DNA for desired traits.

• CRISPR:

  • A tool for precise gene editing.

• Cloning:

  • Creating a genetically identical copy of an organism.

Microbiology

• Bacteria:

  • Prokaryotes, can be beneficial (gut flora) or pathogenic (disease-causing).

• Viruses:

  • Non-living entities that require a host to replicate.

• Fungi:

  • Eukaryotic organisms, decomposers, beneficial (antibiotics) or harmful (fungal infections).

Plant Biology

• Photosynthesis:

  • Process by which plants convert sunlight into energy (glucose) using chlorophyll.

• Plant Anatomy:

  • Roots: Absorb water and nutrients.
  • Stems: Support and transport.
  • Leaves: Site of photosynthesis.

• Plant Reproduction:

  • Sexual (flowers, seeds) and asexual (cuttings, runners).

Cell Biology

• Cell Theory: Core principles that define all living organisms, asserting that they are all made up of cells, identifying the cell as the fundamental unit of life, and concluding that all cells originate from existing cells.
• Cell Types:
  • Prokaryotic Cells: Characterized by the absence of a nucleus, they are generally smaller and simpler, commonly represented by bacteria.
  • Eukaryotic Cells: Distinguished by having a nucleus, these cells are larger and more complex, including plants and animals.
• Cell Organelles:
  • Nucleus: The control center containing DNA.
  • Mitochondria: Often referred to as the powerhouse of the cell, responsible for energy production.
  • Ribosomes: Essential for synthesizing proteins.
  • Endoplasmic Reticulum: Divided into rough (protein synthesis) and smooth (lipid synthesis).
  • Golgi Apparatus: Involved in modifying and packaging proteins.
  • Lysosomes: Function in digestion and waste removal within the cell.

Genetics

• DNA Structure: Composed of two strands forming a double helix, consisting of nucleotides represented by adenine (A), thymine (T), cytosine (C), and guanine (G).
• Gene Expression:
  • Transcription: The process of converting DNA into RNA occurs in the nucleus.
  • Translation: The conversion of RNA into proteins occurs in the cytoplasm.
• Mendelian Genetics:
  • Established the foundation of heredity through the laws of segregation and independent assortment, focusing on dominant and recessive alleles.
• Punnett Squares: A tool used for predicting genetic variation and probability of traits in offspring.

Evolution

• Natural Selection: A fundamental mechanism of evolution where traits that enhance survival are more likely to be passed to subsequent generations.
• Speciation: The evolutionary process through which new species emerge.
• Evidence for Evolution: Supported by fossil records, comparative anatomy, and advancements in molecular biology.

Ecology

• Ecosystems: Made up of biotic (living organisms) and abiotic (non-living elements) components that interact within a defined area.
• Food Chains and Webs: Illustrate the energy transfer from primary producers (e.g., plants) to various consumers, indicating complex interdependencies.
• Biomes: Large ecological zones characterized by specific climate conditions and ecosystems, such as rainforests, deserts, and tundras.
• Population Dynamics: Influenced by factors like birth rates, death rates, immigration, and emigration, affecting overall population size.

Human Biology

• Body Systems:
  • Circulatory System: Responsible for the transportation of blood and essential nutrients throughout the body.
  • Respiratory System: Facilitates gas exchange, primarily oxygen intake and carbon dioxide elimination.
  • Digestive System: Breaks down food into energy and nutrients for bodily functions.
  • Nervous System: Coordinates responses to environmental stimuli and regulates body functions.
• Homeostasis: The mechanism that regulates internal stability in response to external changes, maintaining factors like temperature and pH at optimal levels.

Biotechnology

• Genetic Engineering: Involves altering an organism's DNA to achieve specific desired traits or characteristics.
• CRISPR: A revolutionary tool that allows precise editing of genes, enhancing genetic engineering capabilities.
• Cloning: The technique of creating a genetically identical organism, utilized in various biological research and applications.

Microbiology

• Bacteria: Prokaryotic microorganisms that can be beneficial (e.g., gut flora aiding digestion) or harmful (e.g., pathogens causing diseases).
• Viruses: Non-living infectious agents that lack cellular structure and require a host for replication and spread.
• Fungi: Eukaryotic organisms playing dual roles as decomposers, some being beneficial (source of antibiotics) while others can cause infections.

Plant Biology

• Photosynthesis: The process whereby plants use chlorophyll to convert light energy into chemical energy stored in glucose.
• Plant Anatomy:
  • Roots: Essential for the absorption of water and nutrients from the soil.
  • Stems: Provide structure and transport materials between roots and leaves.
  • Leaves: The primary site for photosynthesis, facilitating energy production.
• Plant Reproduction:
  • Sexual: Involves flowers and seeds for genetic diversity.
  • Asexual: Involves methods such as cuttings and runners for rapid propagation without seed production.

This quiz covers fundamental concepts in cell biology and genetics, including cell theory, types of cells, organelles, and the structure of DNA. It also explores gene expression and Mendelian genetics, focusing on key principles like segregation and independent assortment. Test your knowledge of these essential biological topics.