Cell Structure and Cellular Processes

Cell Structure:
- Plasma membrane: semi-permeable membrane that separates cell from environment
- Cytoplasm: jelly-like substance inside cell membrane
- Nucleus: contains genetic material (DNA)
- Mitochondria: generates energy for cell
- Endoplasmic reticulum: involved in protein synthesis and transport
- Lysosomes: contains digestive enzymes
Cellular Processes:
- Metabolism: conversion of energy and nutrients
- Photosynthesis: process by which plants convert light energy into chemical energy
- Cell division: process of cell growth and reproduction
- Cellular respiration: process of generating energy from glucose

DNA Structure:
- Double helix model: two strands of nucleotides twisted together
- Nucleotides: composed of sugar, phosphate, and nitrogenous bases (A, C, G, and T)
Genetic Inheritance:
- Mendel's laws: rules governing how traits are inherited
- Dominant and recessive genes: determine expression of traits
- Genotype: genetic makeup of an individual
- Phenotype: physical expression of genotype
Genetic Variation:
- Mutation: change in DNA sequence
- Genetic drift: random change in gene frequency
- Gene flow: movement of genes between populations

Ecosystem Components:
- Biotic factors: living organisms (plants, animals, microorganisms)
- Abiotic factors: non-living components (light, temperature, water, soil)
- Producers: organisms that convert light energy into chemical energy
- Consumers: organisms that obtain energy by consuming other organisms
Ecosystem Processes:
- Energy flow: transfer of energy from one organism to another
- Nutrient cycling: movement of nutrients through ecosystem
- Decomposition: breakdown of organic matter
- Succession: process of ecosystem change over time

Mechanisms of Evolution:
- Natural selection: process by which populations adapt to environment
- Genetic drift: random change in gene frequency
- Mutation: change in DNA sequence
- Gene flow: movement of genes between populations
Evidence for Evolution:
- Fossil record: chronological record of extinct species
- Comparative anatomy: study of similarities and differences between species
- Molecular biology: study of DNA and protein similarities between species
- Biogeography: study of geographic distribution of species

Plasma membrane is a semi-permeable membrane that separates the cell from its environment
Cytoplasm is a jelly-like substance inside the cell membrane where metabolic activities occur
Nucleus contains genetic material (DNA) and is responsible for controlling cell growth and reproduction
Mitochondria generates energy for the cell through cellular respiration
Endoplasmic reticulum is involved in protein synthesis and transport
Lysosomes contain digestive enzymes and break down foreign substances and cellular waste

DNA is structured as a double helix, with two strands of nucleotides twisted together
Nucleotides are composed of sugar, phosphate, and nitrogenous bases (A, C, G, and T)
Mendel's laws govern how traits are inherited, including the law of segregation and the law of independent assortment
Dominant and recessive genes determine the expression of traits, with dominant genes overriding recessive genes
Genotype refers to the genetic makeup of an individual, while phenotype refers to the physical expression of that genotype
Genetic variation can occur through mutations, genetic drift, or gene flow

Biotic factors in an ecosystem include living organisms such as plants, animals, and microorganisms
Abiotic factors include non-living components such as light, temperature, water, and soil
Producers convert light energy into chemical energy through photosynthesis
Consumers obtain energy by consuming other organisms, and can be classified into primary, secondary, or tertiary consumers
Energy flows from one organism to another through food chains and food webs
Nutrient cycling involves the movement of nutrients through the ecosystem, with decomposers playing a key role in releasing nutrients back into the environment
Decomposition is the breakdown of organic matter, while succession is the process of ecosystem change over time

Natural selection is the process by which populations adapt to their environment, leading to the survival and reproduction of individuals with favorable traits
Genetic drift is a random change in gene frequency, which can lead to the loss of genetic variation
Mutations are changes in DNA sequence, which can result in new traits or changes to existing ones
Gene flow is the movement of genes between populations, which can lead to genetic changes and increased variation
The fossil record provides a chronological record of extinct species, with transitional fossils providing evidence for evolution
Comparative anatomy and molecular biology reveal similarities and differences between species, providing evidence for evolution
Biogeography, the study of the geographic distribution of species, also provides evidence for evolution

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