Life Science: Cell Biology & Genetics

• Lifescience encompasses the study of living organisms and life processes
• It includes diverse fields such as biology, medicine, and biotechnology
• The goal of lifescience is to understand the structure, function, growth, origin, evolution, distribution, and taxonomy of living organisms

Cell Biology

• Cell biology studies the structure, function, and behavior of cells
• The cell is the basic unit of life
• Key areas include cell structure, cell division, and cell signaling
• Cell structure involves understanding organelles like the nucleus, mitochondria, and endoplasmic reticulum
• Cell division includes mitosis and meiosis
• Cell signaling involves how cells communicate with each other

Genetics

• Genetics is the study of heredity and variation in organisms
• It includes the study of genes, DNA, and chromosomes
• Key areas include Mendelian genetics, molecular genetics, and population genetics
• Mendelian genetics deals with the principles of inheritance
• Molecular genetics focuses on the structure and function of genes at the molecular level
• Population genetics studies the genetic variation within and among populations

Ecology

• Ecology is the study of the interactions between organisms and their environment
• It includes the study of ecosystems, communities, and populations
• Key areas include population ecology, community ecology, and ecosystem ecology
• Population ecology focuses on population size, density, and dynamics
• Community ecology studies the interactions between different species in a community
• Ecosystem ecology examines the flow of energy and nutrients through an ecosystem

Physiology

• Physiology is the study of the functions and mechanisms in a living system
• It explores how organisms, organ systems, organs, cells, and biomolecules carry out the chemical or physical functions that exist in a living system.
• Key areas include organ physiology, cell physiology, and systems physiology
• Organ physiology focuses on the function of individual organs
• Cell physiology studies the function of cells
• Systems physiology examines the integration of functions across different organ systems

Microbiology

• Microbiology is the study of microorganisms, including bacteria, viruses, fungi, and protozoa
• It includes the study of microbial structure, function, and behavior
• Key areas include bacteriology, virology, and mycology
• Bacteriology is the study of bacteria
• Virology is the study of viruses
• Mycology is the study of fungi
• Microbiology also includes areas like immunology and microbial genetics

Common Biological Themes

• Evolution: the process of change in the heritable characteristics of biological populations over successive generations
• Information: the genetic information encoded in DNA and RNA, central dogma of molecular biology
• Structure and Function: the correlation between biological structure and its function at all levels
• Energy and Matter: the flow of energy and matter through ecosystems and organisms
• Systems: the interaction of different components within biological systems, like feedback mechanisms

Cell Structure and Function

• Plasma Membrane: a selective barrier that encloses the cell.
• Cytoplasm: the interior of the cell, consisting of a fluid cytosol with organelles
• Nucleus: contains most of the genes in the eukaryotic cell
• Ribosomes: protein synthesis

Genetic Processes

• DNA Replication: the process by which DNA makes a copy of itself during cell division
• Transcription: the process by which the information in a strand of DNA is copied into a new molecule of messenger RNA (mRNA)
• Translation: the process by which a sequence of nucleotide triplets in a messenger RNA (mRNA) molecule gives rise to a specific sequence of amino acids during synthesis of a polypeptide or protein

Ecological Concepts

• Ecosystems consist of biotic (living) and abiotic (non-living) components
• Food webs illustrate the flow of energy in an ecosystem
• Symbiotic relationships: mutualism, commensalism, and parasitism
• Biomes: major ecological communities, such as forests, grasslands, and deserts

Physiological Regulation

• Homeostasis: the maintenance of stable internal conditions in an organism
• Feedback mechanisms: negative and positive feedback loops
• Endocrine System: regulates body functions through hormones.
• Nervous System: transmits signals rapidly through electrical and chemical signals

Microbial Diversity

• Bacteria and Archaea: prokaryotic microorganisms.
• Viruses: non-cellular entities that require a host cell to replicate
• Fungi: eukaryotic organisms including yeasts and molds
• Protozoa: eukaryotic microorganisms

Cell Communication

• Direct Contact: communication through cell junctions
• Local Signaling: paracrine and synaptic signaling
• Long-Distance Signaling: endocrine signaling

Evolution and Natural Selection

• Natural selection: the differential survival and reproduction of individuals due to differences in phenotype
• Adaptation: inherited characteristic of an organism that enhances its survival and reproduction in a specific environment
• Genetic variation: differences among individuals in their genes or other DNA segments
• Speciation: the evolutionary process by which new biological species arise

Energy Flow in Ecosystems

• Primary producers: autotrophs that convert solar energy into chemical energy
• Consumers: heterotrophs that obtain energy by feeding on other organisms
• Decomposers: organisms that break down dead organic material
• Trophic levels: the position an organism occupies in a food chain

Immune System

• Innate immunity: non-specific defense mechanisms
• Adaptive immunity: specific defense mechanisms against pathogens
• Antibodies: proteins that bind to antigens and neutralize them
• T cells and B cells: lymphocytes involved in adaptive immunity

Plant Physiology

• Photosynthesis: process by which plants convert light energy into chemical energy
• Transpiration: the process of water movement through a plant and its evaporation from aerial parts
• Hormones: regulate plant growth and development
• Nutrient uptake: absorption of essential elements from the soil

Animal Physiology

• Respiration: the process of gas exchange
• Circulation: the transport of blood and nutrients
• Excretion: the removal of metabolic wastes
• Digestion: the breakdown of food to obtain nutrients