Biology Overview: Cells, Genetics, Evolution

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.
• Prokaryotic Cells: Simple structure, no nucleus, DNA in nucleoid, smaller than eukaryotic cells (e.g., bacteria).
• Eukaryotic Cells: Complex structure, nucleus present, membrane-bound organelles (e.g., plants, animals, fungi).

Genetics

• DNA Structure: Double helix, made of nucleotides (adenine, thymine, cytosine, guanine).
• Genotype vs. Phenotype: Genotype is the genetic makeup; phenotype is the observable traits.
• Mendelian Inheritance: Principles of segregation and independent assortment.

Evolution

• Natural Selection: Mechanism of evolution where organisms better adapted to their environment tend to survive and reproduce.
• Speciation: Process by which new species arise, often due to geographic isolation or ecological factors.
• Fossil Record: Evidence of historical life forms, showing changes over time and common ancestry.

Ecology

• Ecosystems: Interactions between living organisms and their environment, including biotic (living) and abiotic (non-living) factors.
• Food Webs: Complex networks of feeding relationships; energy flow from producers to consumers and decomposers.
• Biomes: Large ecological areas (e.g., tundra, rainforest) defined by climate, vegetation, and animal life.

Human Biology

• Organ Systems: Groups of organs working together (e.g., circulatory, respiratory, digestive systems).
• Homeostasis: Maintenance of stable internal conditions despite external changes.
• Immune System: Defense mechanism against pathogens; includes innate and adaptive immunity.

Plant Biology

• Photosynthesis: Process by which plants convert light energy into chemical energy (glucose), primarily occurring in chloroplasts.
• Plant Structure: Roots (absorption), stems (support), leaves (photosynthesis), flowers (reproduction).
• Plant Hormones: Chemicals regulating growth and development (e.g., auxins, gibberellins).

Microbiology

• Bacteria: Single-celled organisms, can be beneficial (gut flora) or pathogenic (disease-causing).
• Viruses: Non-cellular entities that require a host to replicate; consist of genetic material surrounded by a protein coat.
• Fungi: Eukaryotic organisms, important for decomposition and nutrient cycling, can be pathogenic or beneficial (e.g., yeast in fermentation).

Biochemistry

• Macromolecules: Four main types: carbohydrates (energy storage), proteins (catalysts, structure), lipids (membranes, energy), nucleic acids (genetic information).
• Enzymes: Biological catalysts that speed up chemical reactions; function based on substrate specificity and active site.
• Metabolism: All chemical reactions in the body; includes catabolism (breaking down) and anabolism (building up).

Biotechnology

• Genetic Engineering: Modifying an organism's DNA to achieve desired traits (e.g., GMOs).
• CRISPR: A revolutionary method for editing genes with precision.
• Bioremediation: Use of microorganisms to clean up contaminated environments.

Cell Biology

• Cell Theory asserts that all living organisms consist of cells, which are the fundamental units of life, and that all cells originate from existing cells.
• Prokaryotic cells have a simple structure lacking a nucleus; their DNA is located in a nucleoid region and are generally smaller than eukaryotic cells, with examples including bacteria.
• Eukaryotic cells possess a more complex structure, characterized by a nucleus and various membrane-bound organelles; examples include plant, animal, and fungal cells.

Genetics

• The structure of DNA is a double helix composed of nucleotides, which include adenine, thymine, cytosine, and guanine.
• Genotype refers to the genetic constitution of an organism, while phenotype describes the observable physical characteristics resulting from the genotype.
• Mendelian inheritance is grounded in the principles of segregation, where alleles separate during gamete formation, and independent assortment, where genes are inherited independently.

Evolution

• Natural selection acts as a driving force of evolution, favoring organisms that are better adapted to their environments, enhancing their survival and reproductive success.
• Speciation is the process through which new species emerge, often driven by geographic isolation or distinct ecological factors leading to reproductive barriers.
• The fossil record serves as evidence of historical life, showcasing evolutionary changes over time and establishing connections between different species through common ancestry.

Ecology

• Ecosystems consist of dynamic interactions between living organisms (biotic factors) and their physical environment (abiotic factors), influencing both communities and individuals.
• Food webs illustrate the complex feeding relationships among organisms, demonstrating the flow of energy from primary producers to various consumers and decomposers.
• Biomes represent large ecological areas, such as tundras and rainforests, defined by specific climate conditions, vegetation types, and animal populations.

Human Biology

• Organ systems comprise groups of organs that collaborate to perform specific physiological functions, including systems such as circulatory, respiratory, and digestive.
• Homeostasis is the regulatory process maintaining stable internal conditions, such as temperature and pH, despite external environmental fluctuations.
• The immune system acts as the body’s defense against pathogens, featuring both innate immunity (immediate response) and adaptive immunity (targeted response).

Plant Biology

• Photosynthesis is the biochemical process where plants transform light energy into chemical energy, primarily glucose, occurring within chloroplasts.
• Key plant structures include roots for nutrient absorption, stems for support, leaves for photosynthesis, and flowers for reproduction and pollination.
• Plant hormones, such as auxins and gibberellins, play essential roles in regulating various growth and developmental processes.

Microbiology

• Bacteria are single-celled organisms that can perform beneficial roles, such as in gut flora, or cause diseases as pathogens.
• Viruses are non-cellular entities that depend on the host cells for replication, consisting of genetic material encased in a protein coat.
• Fungi are eukaryotic organisms important for ecological processes like decomposition and nutrient cycling; they can also have pathogenic or beneficial roles, such as yeast in fermentation.

Biochemistry

• Four primary macromolecules exist: carbohydrates for energy storage, proteins for catalysis and structure, lipids for membrane formation and energy, and nucleic acids for genetic information.
• Enzymes function as biological catalysts that accelerate chemical reactions, with activity determined by substrate specificity and the configuration of their active sites.
• Metabolism encompasses all chemical reactions within an organism, divided into catabolism (breaking down molecules for energy) and anabolism (constructing molecules for growth and storage).

Biotechnology

• Genetic engineering involves altering an organism's DNA to express desired traits, resulting in applications such as genetically modified organisms (GMOs).
• CRISPR technology provides a method for precise gene editing, enabling targeted modifications at specific locations within the genome.
• Bioremediation utilizes microorganisms to detoxify and restore contaminated environments, playing a vital role in ecological restoration efforts.

This quiz covers fundamental concepts across cell biology, genetics, and evolution. Explore the structure and function of prokaryotic and eukaryotic cells, the principles of inheritance, and the mechanisms of evolution. Perfect for students looking to reinforce their understanding of biological concepts.