Calculation Based: Chi-Squared Tests Chi-Squared Tests Formula Critical Value: the number on the table; figure out your degrees of freedom, and ALWAYS use 0.05 This means that you are 95% sure of it being accurate (if you pick...
Biology
Biogeochemical Cycles
Biogeochemical cycles: describe flow of essential elements from the environment to living things and back to environment Studies the rate of element movement between reservoirs & interaction of the current cycle with other cycles FRQ: if question asks about flow...
Biodiversity
“Describes the number of species, niches, and trophic levels in the ecosystem and the complexity of its food web” Factors that influence biodiversity… Climate: influences abundance and type of primary producers and number of species primary production can support...
Ecological Succession
Ecological succession is the progression of life from an uninhabited state to a fully functional and healthy ecosystem. Ex: one community with certain species is gradually and predictably replaced by another community of diff species As succession progresses, species...
Community Ecology
Community ecology is concerned with the interaction of populations Communities and ecosystems are described with regards to the interactions between organisms and environment, biodiversity, and species diversity and composition (identity of species) Species Diversity...
Population Ecology
“Study of the growth, abundance, and distribution of populations” Population abundance and distribution are described by… Size (N): total number of individuals in the population Density: total number of individuals per area occupied Adding = thru birth or immigration;...
Energy Flow in an Ecosystem
Food chain: linear flow chart of who eats whom and direction of nutrient and energy transfer Food web: linked group of food chains (animals have more than one food source) Conservation of Mass Matter, like energy, cannot be created or destroyed. But elements can...
Climate
Long-term conditions in an area Four physical factors— temperature, precipitation, sunlight, and wind Climograph: plot of the annual mean temperature and precipitation in a particular region Global Climate Patterns Determined largely by the input of solar energy...
Communication in Animals
Signal: A stimulus transmitted from one organism Communication: the transmission and reception of signals between animals of same species Common modes of animal communication: visual, chemical, tactile, auditory, Uses: indicate dominance, find food, establish...
Animal Rhythms
Circadian rhythm: pattern of behavioral activity aligned with 24 hour cycle (AKA biological clock); daily cycle of rest and activity Can persist without external cues but cues can help → light can maintain synchronization Biological rhythms can be linked to light/dark...
Animal Behavior
Review Behavior: reaction of living things to stimuli (either from the physical environment or other living things) Behaviors may be encoded in DNA or learned; group behaviors or individual Behavior used to maintain homeostasis, find mates and nutrients Proximate...
Kingdom Animalia
Similarities among all members Multicellular & heterotrophic Dominant generation in the life cycle is diploid Most are motile during at least some part of life
Kingdom Plantae
Similarities among all plants Multicellular; cell wall Autotrophic Rooted in the ground Organs & Interactions with the Environment Roots: anchor plants to the ground; absorb water and nutrients. Water capacity of roots improved by increasing absorbing surface area...
Kingdom Fungi
Structure Grow as filaments called hyphae; mass of hyphae is called mycelium Some have septa (cross walls) which divide the filament into compartments containing single nucleus Cell walls consist of Chitin: nitrogen-containing polysaccharide Ecological Interaction...
Kingdom Protists
Extremely diverse: can be algae-like, animal-like, fungus-like; unicellular, multicellular Evolutionary relationships are weak, poorly understood, or both Features shared by two or more groups may represent convergent evolution Algae-Like All obtain energy by...
Domain Archaea
What makes Archaea Different? Cell walls contain diff polysaccharides, not peptidoglycans, cellulose, or chitin Plasma membrane contain different phospholipids What Makes Archaea Similar Like bacteria, are prokaryotes Like eukaryotes, are not inhibited by antibiotics...
Domain Bacteria
Characteristics of Prokaryotes: Small size and rapid reproduction High genetic variation → live in diverse environments Bacteria Structure and Review Cell wall: made with peptidoglycan (carb polymer...
Modes of Nutrition
Autotrophs: make their own organic molecules Photoautotrophs Use light energy (as in photosynthesis) Chemoautotrophs Use energy obtained from inorganic substances (as in chemosynthesis) Heterotrophs: obtain carbon & energy from other organisms Parasites Obtain...
Prokaryotes vs Eukaryotes
Prokaryotes: unicellular, microorganisms that lack organelles Archaea & bacteria Cell Type Prokaryote Eukaryotes Size Smaller Bigger Multi or Uni Uni Multi Organelles No (Nucleus) Yes (Nucleus) Cell Wall Yes Plants, Fungi, and some Protists Cytoplasm No...
Common Ancestry
It is believed that all organisms share a common ancestor, There are FOUR features that support common ancestry: DNA and RNA are carriers of genetic information Ribosomes are found in all forms of life Universality of the genetic code and gene expression Core...
Phylogeny
“Evolutionary history of a species” Determined through fossils, homologous structures, morphology, & molecular biology Taxonomy: classification of organisms; organisms are classified into categories called taxa Hierarchical Classification Each taxon more inclusive...
Speciation
Species Concept Biological species concept: species is a group of populations that can breed and produce viable offspring Defined by reproductive isolation and gene flow; basis for understanding macroevo. Morphological species concept: distinguishes a species by body...
Hardy-Weinberg Equilibrium
When the allele frequencies in a population remain constant from generation to generation, the population is said to be in genetic equilibrium or Hardy-Weinberg Equilibrium At genetic equilibrium, there is no evolution But allele representation in generations might...
Sources of Variation
Genetic Variation: difference in DNA bases or sequences Genetic variation enables evolutionary responses to environmental change Evidence of genetic variation: diff genotypes or phenotypes Natural selection acts on variation among individuals in the population and...
Natural Selection
Process in which individuals with certain inherited characteristics are more likely to survive in an environment, reproduce and pass on those traits → traits have selective advantage Environment is the main force behind natural selection → controls which traits are...
Evolution
Review Basic idea: “Descent with modification, change in genetic composition over time from generation to generation” Specific: the process by which frequency of heritable traits in population changes from one generation to the next A population is evolving if their...
Viruses
Normal Flow: DNA, RNA, Protein Retrovirus: RNA, DNA, RNA, Protein Virus Function Virus: small nucleic acid genome enclosed in capsid Penetrates cell → takes over metabolic machinery → assembles new virus copies Virus Structure Nucleic Acid: either RNA or DNA which...
Mutations
A change in the sequence of nucleotides in an original DNA molecule Mutations are irreversible and the main cause of genetic variation (alleles) Mutations can cause changes in phenotype (ex. cystic fibrosis) or disorders Alterations in DNA can lead to changes in type...
Concerns About Biotechnology
Improvements in the identification and treatment of disease. But some benefits can be abused. Social and ethical questions include… Pharmaceuticals: DNA cloning allows quick and inexpensive production of pharmaceuticals Ex: human insulin and human growth hormone (HGH)...
Gel Electrophoresis and DNA Fingerprinting
Gel Electrophoresis: a procedure that separates restriction fragments DNA fragments of diff lengths are separated as they diffuse thru a gelatinous material under influence of an electrical field DNA has same charge per...
Polymerase Chain Reaction (PCR)
PCR: a technique that makes large number of DNA copies faster than DNA cloning process DNA is heated. Heating denatures (separates) hydrogen bonding holding the dsDNA together and forms two ssDNA molecules DNA is cooled and ssDNA primers are added. Two primers are...
DNA Cloning
Procedure that allows DNA fragments or genes to be copied Use a restriction enzyme to cut up the foreign DNA that contains a gene to be copied. The restriction enzyme produces multiple fragments of foreign DNA with sticky ends Use the same restriction enzyme to cut up...
Biotechnology
Making Multiple Copies of a Gene or DNA Segment Recombinant DNA: contains DNA segments or genes from diff sources One part of DNA molecule, chromosome or organism to another Transfer of DNA segments can happen naturally thru viral transduction, bacterial conjugation,...
Differentiation and Stem Cells
Stem Cells: unspecialized cells during early stage of embryonic development that can reproduce indefinitely and differentiate (become any) into specialized cells But as development continues → cells differentiate & become specialized → cell divisions make more...
Factors That Influence Embryonic Development
Specific genes expressed in cell during development determine cell type Cell can receive external and internal cues that cause regulation of gene expression by turning genes on/off External: cells receive signals from extracellular environment Adjacent cells: ex:...
Methods of Gene Regulation
DNA Methylation: Histone Acetylation Homeotic Genes: master genes that control the pattern of body formation during early embryonic development Ex: in flies genes control formation of body structures like body segments and antenna Mutant homeotic genes produce body...
Regulation of Gene Expression: Prokaryotes Vs. Eukaryotes
Bacteria Coordinately controlled genes clustered in operon regulated by one promoter Prokaryotic regulation mostly at transcriptional level Prokaryotes don’t have RNA splicing or chromatin modification Operon “Unit of DNA that contains functionally related genes that...
Translation
Translation is where RNA is turned into proteins for the cell to use. In Eukaryotes, after transcription & processing mRNA, tRNA, and ribosomal subunits are transported across the nuclear envelope and into the cytoplasm In cytoplasm, a specific amino acid attaches...
mRNA Processing: Enzyme Regulated Modifications of mRNA transcript:
In Eukaryotes, mRNA transcript must be processed before can exit the nucleus and be used for translation → Pre-mRNA longer than post mRNA 5’ Cap: is added to the 5’ end of mRNA ...
Transcription
Transcription is where DNA strands are turned into RNA strands for translation to use. Initiation: RNA polymerase recognizes & attaches to a promoter sequence on the DNA and begins to unzip them into two strands Promoter Sequence: DNA sequence which starts...
Helpful Images
Replication Proteins Lagging Strand Leading Strand
Summary: The Process of DNA Replication
Helicase unwinds the parental double helix at the origin of replication→ forms a Y-shaped replication fork Origin of replication: short, stretch of DNA with a specific sequence of nucleotides Single-stranded binding protein attaches to each strand of uncoiled DNA to...
The Role of DNA Polymerase
DNA Polymerase I vs. III Both can only add DNA to 3 end Polymerase I Responsible for removing RNA primers on replacing with DNA nucleotides Polymerase III Uses parental DNA to add DNA nucleotides 3’ end of RNA primers or existing strand...
“Semiconservative”
Before duplication, hydrogen bonds between bases are broken → double strands unwind and separate into single strands → each strand serves as a template for new, complementary strand → replicated DNA consists of a single strand of old DNA (template strand) and a single...
DNA Replication Proteins & Their Functions
Helicase Unwinds parental double helix at replication forks Single-stranded binding protein Binds to, stabilizes, and prevents single-stranded DNA from rejoining until is is used as a template Topoisomerase Binds ahead of replication forks & relieves overwinding...
Chromosome Theory of Inheritance
“Genes have specific loci along chromosomes & undergo segregation and independent assortment” Chromosomal inheritance generates genetic variation in sexual reproduction. Evidence: parallels between genes during meiosis and behavior of chromosomes Autosomal...
Chromosomal Inheritance and Environment Effects on Phenotype
Multifactorial characters: many factors, such as genes and environment affect phenotype Pedigree Analysis: Square is male, circle is female, painted in means they have that trait X-linked dom → father passes to all daughters; X-linked recessive → mother passes to all...
Rules of Probability
Rules of probability can be applied to analyze passage of single-gene traits from the parent to the offspring. For harder problems, where there are 2 alleles (AaBb) Mutually exclusive (can’t happen at...
Mendel’s Crosses
P generation: Parental generation, Mendel crossed a purebred purple with a purebred white plant People used to believe in blending inheritance: traits are mixed Ex: a tall person mates with short person = medium height baby F1 generation: created only purple plants,...
Meiosis: Key Overview
Meiosis: specialized cell division that yields 4 nonidentical, haploid gametes in sexually reproducing diploid organisms Only occurs specialized (diploid) cells like testes & ovaries in humans to make sperm and egg Involves two rounds of division (meiosis 1 &...
Sexual Life Cycle
Sexual Life Cycle: alteration of halving and doubling chromosome count in each generation In sexual reproduction two parents produce offspring with a unique combination of genes. In eu. results in gamete formation Increases genetic variation bcuz random mutations can...
CANCER & Disruptions to the Cell Cycle
Disruptions to cell cycle or inability to carry out apoptosis can lead to cancer Cancer Cells Cancer: unregulated/out of control cell division, results from genetic changes affecting genes whose proteins regulate the cell cycle Normal cells become cancer cells by the...
Regulations of the Cell Cycle
Internal Regulation of the Cell Cycle Functional Limitations Surface-to-volume ratio: when surface area is small compared to volume → cell growth stops or cell division begins Genome-to-volume ratio: ability of genome to function is limited by by finite amount of...
Mitosis: The Process
G2 of Interphase Prophase (condensation) Prometaphase The last part of interphase: - A nuclear envelope encloses the nucleus. - Nucleoli usually present in nucleus - Two centrosomes have formed by duplication - Each centrosomes contain two centrioles -...
Mitosis Overview
Cell Cycle: is a highly regulated series of events for the growth and reproduction of eukaryotic cells Three stages: Interphase, Mitosis, & Cytokinesis Smaller cells better because easier to coordinate chromosomes and microtubules with less ATP DNA content doubles...
Mutations in the Pathway
A change/mutation in the structure of a receptor protein or signaling molecule affects the activity of the signaling pathway and can alter the cellular response Chemicals that interfere with any component of the signaling pathway may activate or inhibit it: toxins,...
APOPTOSIS
Cell undergoes programmed cell death where cell components are orderly disposed of Cell shrinks and then lysosomes’ hydrolytic proteins (proteases, amylases [carbs], nucleases, etc.) fragment DNA and organelles that are packaged vesicles digested by white blood cells...
THE PROCESS – PART 2: TRANSDUCTION
After the ligand binds, the intracellular domain of the receptor protein changes shape, initiating transduction of the signal by converting it into a form that causes cell response Main Idea: molecules interact with each other to relay/amplify signal SECOND MESSENGERS...
THE PROCESS – PART 1: RECEPTION
Signaling Molecules: small molecules that bind to larger receptors of specific target cells Hydrophilic ligands: cannot cross membrane and bind to membrane receptors Ex: proteins that are both large and polar...
Phosphorylation
The addition of a phosphate group to one or more sites on the protein, which alters the activity of the protein Usually exchanges hydroxyl R group with phosphate Switches proteins on → increases potential energy and ability for chemical work Protein phosphorylation...
Photosynthesis vs. Cellular Respiration
Similarities Photosynthesis - Electrons are sent to the ETC for the light-dependent reactions using a carrier - Existence of a proton gradient in the thylakoid space that passes through ATP Synthase to make ATP - Similar electron carriers Cellular Respiration - ...
Lactic Acid Fermentation
Pyruvate directly reduced by NADH Result: NAD+ regeneration & ATP Waste: lactate (no CO2) In animals, lactic acid often transported to the liver to be turned into pyruvate when there is enough ATP Fermentation vs Anaerobic vs Aerobic Diff: methods of...
Fermentation
Allows glycolysis to proceed when there is no oxygen → produces organic molecules, including alcohol and lactic acid, as waste products. Goal: To replenish NAD+, so glycolysis can make ATP (w/o oxygen) Uses substrate-level-phosphorylation Makes 2 ATP (less but...
ELECTRON TRANSPORT CHAIN
Transfers energy from electrons that move down it thru electron carriers that alternate between reduced and oxidized → released energy used to establish an electrochemical gradient of protons (H+) across the inner mitochondrial membrane ...
KREBS CYCLE
Occurs in the mitochondrial matrix; cytosol of prokaryotes Begins when 2-carbon Acetyl CoA combines with 4-carbon OAA (oxaloacetate) to form citrate Citrate functions as inhibitor of glycolysis Result: 2 CO2 molecules produced 6 NADH...
GLYCOLYSIS
Process that breaks down glucose and releases energy to form: 2 Pyruvate (stores potential energy) Pyruvate is acidic 2 (net) ATP (from ADP) NADH (from NAD+) Inorganic phosphate 2 Stages Energy Investment: invests 2 ATP to get glycolysis started Energy Payoff: creates...
Enzymes
What are Enzymes? Enzyme: globular catalytic protein All enzymes are catalysts, but not all catalysts are enzymes Catalyst: chemical agent that speeds up a reaction without being consumed by the reaction → can be used over and over again Do not affect the free energy...
ATP
Principle molecule for storing and transferring energy for cell work and activation energy; converted by enzymes Structure Basically RNA adenine nucleotide with two more phosphates Nitrogenous base (adenine)...
Free Energy Change
Free Energy: portion of systems energy that can perform work when temperature and pressure are uniform throughout (not heat) Formula ΔG= ΔH-TΔH ΔG= Free energy change ΔH = Enthalpy, change in total energy/heat content ΔS = Entropy, what's lost as heat Spontaneous...
Concentration Gradients
The selective permeability of membranes allows for the formation of concentration gradients of solutes across the membrane Concentration Gradients: “Difference of concentration between two substances” Diffusion: movement of molecules so they spread out evenly Steeper...
Membrane Transport
The Phospholipid Bilayer Cell membranes are asymmetrical bcuz the two sides of a cell membrane face different environments and carry out different functions The polar phosphate regions are oriented towards the aqueous external or internal environments The nonpolar...
Cellular Organelles
Cell: basic functional unit of all living things bound by a plasma membrane Cytoplasm: contains organelles suspended in a fluid matrix (cytosol) which consists of water and dissolved substances like proteins and nutrients Organelles: Internal membrane bound bodies...
1.4: Properties of Biological Macromolecules
Structure and function of polymers depends on the chemical properties and assembly of their monomers Macromolecule: chains of polymers linked together Polymers: large molecule made up of monomers joined by covalent bonds Monomer: single repeating subunit Nucleic...
1.3: Introduction to Biological Macromolecules
Dehydration Synthesis and Hydrolysis Used to cleave and form covalent bonds between monomers
1.2 Elements of Life
Carbon is essential for all life → leads to diversity, forms cell structure, and is used to build all macromolecules Diversity of organisms due to carbon's ability to build long chains of itself, bond to lots of molecules & form a wide variety of compounds...
1.1: Structure of Water and Hydrogen Bonding
The subcomponents of biological molecules and their sequences determine the properties of that molecule Properties of Water Water: 2 hydrogen and 1 oxygen bonded together with (Polar) COVALENT bonds bcuz oxygen is more electronegative, so electrons pulled closer to it...
Chemistry
Trace Elements: required by organisms in minute amounts Essential elements: C, H, O, N (most abundant) Atom “Smallest unit of an element; consists of nucleus of (+) protons and neutrons” Electrons orbit the nucleus Mostly energy, negligible mass Stay at fixed energy...