Ecosystems: Types and Components

Definition: A community of living and non-living components interacting with each other in a specific environment
Components:
- Biotic factors: living organisms (plants, animals, microorganisms)
- Abiotic factors: non-living components (water, air, soil, sunlight)
Types of ecosystems:
- Terrestrial (land-based): forests, grasslands, deserts
- Freshwater: rivers, lakes, wetlands
- Marine: oceans, coral reefs
- Artificial: agricultural fields, urban areas
Energy flow:
- Producers (plants, algae): convert sunlight into energy through photosynthesis
- Consumers (herbivores, carnivores): obtain energy by consuming other organisms
- Decomposers (microorganisms): break down organic matter into nutrients

Definition: the study of heredity, genes, and genetic variation
Key concepts:
- DNA (deoxyribonucleic acid): molecule containing genetic information
- Genes: segments of DNA that code for specific traits
- Alleles: different forms of a gene
- Genotype: genetic makeup of an individual
- Phenotype: physical expression of an individual's genotype
Inheritance patterns:
- Mendelian inheritance: laws of inheritance discovered by Gregor Mendel
- Dominant and recessive alleles
- Punnett squares: tool for predicting genotype and phenotype probabilities

Definition: the process of change in the characteristics of a species over time
Mechanisms:
- Natural selection: survival and reproduction of individuals with advantageous traits
- Genetic drift: random changes in gene frequency
- Mutation: changes in DNA sequence
- Gene flow: movement of genes between populations
Evidence for evolution:
- Fossil record: preserved remains of ancient organisms
- Comparative anatomy: similarities and homologies between species
- Molecular biology: similarities in DNA and protein sequences
- Biogeography: geographic distribution of species

Definition: the study of the structure, function, and behavior of cells
Cell components:
- Cell membrane: permeable membrane surrounding the cell
- Cytoplasm: gel-like substance inside the cell membrane
- Nucleus: contains genetic material (DNA)
- Mitochondria: generate energy for the cell through cellular respiration
- Endoplasmic reticulum: involved in protein synthesis and transport
Cellular processes:
- Cell division: mitosis (somatic cells) and meiosis (gametes)
- Photosynthesis: conversion of light energy into chemical energy
- Cellular respiration: generation of energy from glucose

Definition: the study of the functions and processes that occur within living organisms
Organ systems:
- Nervous system: control and coordination of body functions
- Circulatory system: transport of oxygen and nutrients to cells
- Respiratory system: exchange of oxygen and carbon dioxide
- Digestive system: breakdown and absorption of nutrients
- Endocrine system: regulation of hormones and bodily functions
Homeostasis: maintenance of a stable internal environment despite external changes
Feedback mechanisms: negative feedback loops to maintain homeostasis

A community of living and non-living components interacting with each other in a specific environment
Biotic factors include living organisms such as plants, animals, and microorganisms
Abiotic factors include non-living components like water, air, soil, and sunlight
Terrestrial ecosystems include forests, grasslands, and deserts
Freshwater ecosystems include rivers, lakes, and wetlands
Marine ecosystems include oceans and coral reefs
Artificial ecosystems include agricultural fields and urban areas
Producers convert sunlight into energy through photosynthesis
Consumers obtain energy by consuming other organisms
Decomposers break down organic matter into nutrients

The process of change in the characteristics of a species over time
Natural selection involves the survival and reproduction of individuals with advantageous traits
Genetic drift involves random changes in gene frequency
Mutation involves changes in DNA sequence
Gene flow involves the movement of genes between populations
The fossil record provides evidence of evolution through preserved remains of ancient organisms
Comparative anatomy reveals similarities and homologies between species
Molecular biology reveals similarities in DNA and protein sequences
Biogeography shows the geographic distribution of species