Cell Biology Basics: Structure, Function, and Processes
- The Basic Unit of Life: The cell is the fundamental structural and functional unit of all living organisms.
Cell Structures and Functions
Lysosomes
Lysosomes are cellular organelles that contain enzymes for digestion and waste removal.
Digestive Processes
Lysosomes play a key role in intracellular digestion.
Centrioles
Centrioles are involved in cell division.
Mitochondria
Cells with high energy demands, such as stomach cells, have a greater number of mitochondria.
Ribosomes
Ribosomes are responsible for protein synthesis.
Nucleus
The nucleus controls cellular functions.
ATP
Adenosine triphosphate (ATP) is the primary energy currency of the cell.
Cellular Processes
Microtome
A microtome is used to make thin sections of tissues for microscopic examination.
ATP Function
ATP molecules store and release energy.
Chloroplasts and Photosynthesis
Chlorophyll within chloroplasts captures light energy to convert carbon dioxide and water into glucose and oxygen.
Enzymes
Enzymes are biological catalysts that control energy use in mitochondria and other cellular processes.
Endoplasmic Reticulum
The endoplasmic reticulum connects the nucleus with the cytoplasm and facilitates communication within the cell.
DNA
DNA is the genetic material of the cell.
Nucleotides
Nucleotides are the building blocks of DNA.
RNA and Protein Synthesis
RNA transmits the genetic message from DNA to ribosomes for protein synthesis. A mutation in the RNA sequence for glycine can affect protein synthesis.
Cellular Transport
Diffusion: CO2 is removed from cells by diffusion.
Osmosis: Water moves across a semipermeable membrane from an area of high concentration to an area of low concentration.
Pinocytosis: Cells absorb water and small particles through pinocytotic vesicles.
Biomolecules
Carbohydrates: The most abundant organic molecules in nature.
Proteins: Formed by chains of amino acids.
Starch: A storage form of energy in plants.
Enzymes: Act as organic catalysts in energy release.
ATP: Provides energy for cellular processes.
Cell Division
Mitosis: The process of cell division.
Prophase: Chromosomes condense and become visible.
Metaphase: Chromosomes align at the center of the cell.
Meiosis: A specialized type of cell division that produces gametes (sex cells).
Plant Biology
Photosynthesis Requirements: CO2, water, and sunlight.
Xylem: Transports water and minerals from roots to leaves.
Phloem: Transports sugars from leaves to other parts of the plant.
Stomata: Regulate gas exchange and transpiration.
Reproduction
Asexual Reproduction: Produces offspring genetically identical to the parent.
Sexual Reproduction: Involves the exchange of genetic material between two parents.
Genetics
DNA Structure: Watson and Crick proposed the double helix model of DNA.
mRNA: Carries genetic information from DNA to ribosomes.
Evolution
Natural Selection: The process by which organisms best adapted to their environment survive and reproduce.
Evidence for Evolution: Fossil records, anatomical similarities, and molecular evidence.
Human Biology
Digestive System: Breaks down food for absorption of nutrients.
Circulatory System: Transports oxygen, nutrients, and waste products throughout the body.
Respiratory System: Exchanges oxygen and carbon dioxide.
Nervous System: Controls and coordinates body functions.
Endocrine System: Regulates body functions through hormones.
Other Topics
Bacteria: Single-celled organisms that lack a defined nucleus.
Viruses: Infectious agents that can cause diseases.
Immunity: The body’s defense against pathogens.
Ecology: The study of interactions between organisms and their environment.