SCIENCE AND BIOLOGY Observational studies: real world, no manipulation, correlations Experimental studies: manipulation, test and control groups, cause and effect Independent: manipulated factor Dependent: characteristic measured Control: constant variable k Classification of life: - domain eukaryote, eubacteria, archaebacterial - kingdom animals, plants, fungi, etc. phylogenetic trees: evolutionary history and species relationships EVOLUTION AND NATURAL SELECTION Theory: explanation of broad observations supported by evidence Theory of evolution: common ancestry and decent with modification - relation to natural selection: explains how evolution occurs o heritable traits, help reproduce other versions fitness: ability of an individual to produce offspring adaptation increases fitness in an environment effects of natural selection: - disruptive: removed intermediate phenotypes - directional: eliminates phenotypes at one end - stabilizing: favors intermediate phenotype genetic variation: material for natural selection homologous traits: similar structure, same evolutionary origin analogous trait: similar structure, different evolutionary origin evidence for evolution: natural and artificial selection, fossils ANIMAL BEHAVIOR Comparative psychologists: lab setting Ethologists: natural environment Understanding behavior: 1. causation 2. development 3. function/adaptive value (fitness) 4. phylogeny (evolution) evidence for genetics of behavior: artificial selection, twin studies, mutations types of learning: - simple learning o habituation: decreased response over time o sensitization: increased response due to aversive stimulus - associative learning: o classical conditioning: association of 2 stimuli (Pavlov) o operant conditioning association of behavior with its consequences (award or punishment) - spatial learning: info about environment is acquired, stored, organized, and used CELL BIOLOGY/STRUCTURE cell theory: - all organisms made up of one+ cells - smallest living things - come from pre-existing cells cell structure/unit: - proteins: perform most of the cells functions - nucleic acids: store, transmit, and process info - carbs: chemical energy, carbon, support, and identity - plasma membrane: selectively permeable membrane barrier Prokaryote No nucleus Lack of organelles Asexual reproduction Small BOTH DNA Plasma membrane Cytoplasm Ribosomes Eukaryote Nucleus Mitochondria Sexual reproduction Large Nucleus: largest organelles, surrounded by nuclear envelope, contains DNA Ribosomes: RNA and protein complexes in cytoplasm, synthesize proteins Endomembrane system: endoplasmic reticulum, Golgi apparatus, vesicles, lysomes Mitochondria: energy-rich molecules ATP, supply to cells Chloroplasts: photosynthetic cells, convert light energy to sugar Cell membrane: separates and controls passage of material outside the cell - maintains structural support, acts as receptor sites - made up of proteins, lipids, carbs, and phospholipid bilayers cytoskeleton: provide shape and strength to the cells, allow for movement - microfilaments: movements, dynamic intermediate filaments: rigid, long lasting microtubules: centrioles, axonal transport CELL DIVISION Mitosis Somatic cells 1 division No crossing over Produces 2 cells Meiosis Reproductive cells 2 divisions Crossing over occurs Produces 4 cells Phases of the cell cycle: 1. interphase: G1, S, G2 2. mitosis: prophase, prometaphase, metaphase, anaphase, telophase 3. cytokinesis steps of cell division: 1. DNA synthesis: copying the DNA 2. Mitosis or meiosis: separating the copies 3. Cytokinesis: dividing the cytoplasm to create 2 complete cells Gap phases: where cells are allowed to grow and replicate organelles Step of mitosis: 1. Prophase: condensed chromosomes, spindle starts to move 2. Metaphase: chromosomes line up in middle 3. Anaphase: centromeres divide, move towards opposite side of cell 4. Telophase: spindle disassembles, nuclear envelope reforms Regulation of cycle: - 4 checkpoints: cells determine if division continues - Factors affecting: o Size, nutrient availability, signals from other cells, damage to DNA (apoptosis) Tight junctions: membrane proteins in adjacent animal cells Desmosomes: made of proteins that link cytoskeletons of adjacent cells Signaling molecules: - Neurotransmitters: influence adjacent cells - Hormones: info carrying molecules Lipid soluble hormones: diffuse across the plasma membrane - Receptors are in target cells cytoplasm Lipid insoluble hormones: do not cross the plasma membrane - Receptors are on the cells plasma membrane ENERGY energy cycle: ATP+H2O⇋ADP+Pi+energy ΔG = negative Spontaneous ΔG = positive Non-spontaneous Exergonic Endergonic Energy released Energy must be supplied More free energy (G) with reactants More free energy (G) with products Catalysts: substance that increases the rate of a reaction Regulatory molecules: control when and where an enzyme functions - Change enzymes structure - Ability to bind to its substrate - Activate/inactivate enzymes function Competitive inhibition: molecule competes with the substrate for the active site Allosteric inhibition: molecule binds at a location other than its active site INHERITANCE Genotype: genetic makeup Phenotype: proteins responsible for determined traits Pure lines: result of inbreeding, same characteristics throughout generations Hybrids: offspring of 2 different species Theory of blended inheritance: inheritance of traits from 2 parents produces offspring, characteristics intermediate between those of the parents Mendel’s experiments: purples (dominant) white (recessive) male (round seeds) female (wrinkled seeds) Independent assortment: alleles of different genes are transmitted independently of each other Codominance: black+white chicken=black and white spotted chicken Incomplete dominance: pink rose GENE EXPRESSION Structure of DNA: Nitrogenous base, sugar, phosphate (ATCG) Genetic code: base combo specifies amino acids Central dogma of biology DNA RNA protein - Transcription: DNA RNA - Translation: mRNA Proteins DNA: double stranded, deozyribose, ATCG RNA: single stranded, ribose, AUCG Mutation: permanent change in DNA— Point mutations: one or a small number of base changes - Silent: does not change code - Missense: changes 1 amino acid - Nonsense: changes to stop codon - Frame shift: code out of register Chromosome-level mutations: change chromosome number/structure - Inversion, translocation, deletion, duplication PCR: makes copies of DNA - Open DNA, add primes and match nucleotides CRISPR-Cas9: target viral DNA for destruction - Generates breaks in eukaryotic genomic DNA - Changes to genome sequence Epigenetics: changes in organisms caused by modification of gene expression rather than the genetic code - Affected by environment, nutrition, stress, and drugs Nervous system: - Maintain homeostasis, collect information, process information, produce an appropriate response CNS: brain, spinal cord PNS: ganglia and nerves Sympathetic: - Ach and norepinephrine - Fight or flight response - Short pathways, faster system - Thoracic and lumbar regions of spinal cord Parasympathetic: - ACh and ACh - Homeostatic functions Long pathways, slower system Medulla, cranial nerves, sacral region of spinal cord Brain structure: - Four lobes: o Frontal lobe: primary/secondary motor cortex, personality, decision making, problem solving, emotions o Parietal lobe: movement, orientation, recognition, perception o Occipital lobe: vision o Temporal lobe: auditory, memory, speech Cerebellum: coordination of movement, balance Hypothalamus: neuroendocrine control Cerebral cortex: higher cognitive functions, integrate and interpret sensory info organize motor output Hippocampus: memory, emotion Action potentials: when a stimulus first causes sodium channels to open and then different ions cross the neuron membrane Synapses: connection that allows communication between adjacent cells Broca: speech deficits though they still can read and understand language Wernicke: inability to speak sensibly or understand spoken or written language Split brain: corpus callosumm cut, normal function until task requires two hemispheres to communicate Neuron structure: cell body, dendrites, axon Neuron function: sensory, integrators, motor Reflex arc: neural pathway that controls a reflex NEUROBIOLOGY muscle fibers involved in contraction: - actin filaments consist of a twisted chain of actin molecules - myosin filaments are bundles of many myosin molecules biological rhythm: - cycle in the physiological processes of living beings - originate internals, although they can affect by external causes i.e. sunlight and temp biological clock: term of the area of the hypothalamus that’s responsible for controlling our levels of alertness REM: accelerated respiration, increased brain activity, eye movement, muscle relaxation Non-REM: slowed heart rate, decreased in body temperature, decreased respiration, tissue regeneration, no eye movement Stages of Non-REM - hypothalamus: nerve centers for sleep vs. awake - brain stem: control wake sleep transition - pineal gland: produce melatonin - thalamus: external information—shut down during non-REM, active during REM memory: immediate memory working memory long-term memory limbic system structures: hypothalamus, hippocampus, amygdala - emotions, instincts, and memory HORMONES Hormone: chemical messenger produced and released by specialized glands released into the blood, where they travel to act on target structures away from their origin Hydrophilic: through the blood stream for transport to target cells Lipophilic: bind to transport proteins then enter the lipid membranes System responsible: endocrine system Major components: glands, hormones, targets Feedback loops: negative, where a hormone that is released will inhibit its own release (direct or indirectly), keeps levels from getting too high Pituitary gland: master gland - anterior, 4 hormones, not stored o ACTH, gonadotropins, thyrotropin, growth hormone - Posterior: 2 hormones, stored until needed o Oxy, ADH Adrenal medulla: epinephrine flight or fight response Adrenal cortex: - glucocorticoids: stress response, glucose metabolism - mineralocorticoid: sodium homeostasis - reproductive steroids: normally small amounts glucose regulation: - pancreas: alpha cells produce glucagon, beta cells produce insulin insulin stimulates glucose uptake cells, lowers blood glucose glucagon raised blood glucose hormones effect on behavior: - input systems (sensory), integrators (CNS), output systems (muscles) - don’t change behavior alone, influence the system so the stimulus is more likely to elicit a certain response SENSORY SYSTEMS Major systems: sight, smell, taste, touch, vestibular, hearing, proprioception Chemoreceptors: smell and taste Mechanoreceptors: tactile, hearing, vestibular Photoreceptors: vision Other energy detecting: thermoreceptors, electroreceptors How a sense is processed: stimulus transduction transmission interpretation Taste: tongue, papillae, taste bud Touch: - merkels disk: slow adapting, things touching the skin - meissners corpuscle: fast adapting, superficial in skin, detects light touch - ruffinis ending: medium adapting, middle of skin - pancian corpuscle: fast adapting, deep in dermis hearing: - cochlea: responsible for transmitting sounds - semicircular canals: part of the vestibular system that control balance auditory receptors: - tone: determined by the location of the stimulated hair cells - localization comparing the loudness and timing how do we see an image? - Light enter cornea, pupil regulates the amount of light entering retina turn light into image signals o Cone and rods: day(color) and night (black and white) vision Nearsighted eye: too long, focus on front of retina Farsighted eye: too short, focus behind retina Sensory and memory: - Remembering a place, pic, scene, or event sensory processing activated - Sensory input causes a memory: food, smell, photo bring back a memory Asexual: offspring identical to parent and siblings - Advantage: efficient, occurs in small populations - Disadvantage: no genetic diversity, no evolution of genes Sexual: recombination of genes during meiosis and mating - Advantage: genetic diversity, evolutionary change - Disadvantage: time consuming, risky Processes: - Gametogenesis: production of gametes - Mating: anatomical, physiological, behavioral adaptions to get 2 individuals together - Fertilization: fusion of gametes Male reproductive hormones: testosterone GnRHLH Leydig Female reproductive hormones: FSHLHestrogenprogesterone Sexual selection: - Intrasexual selection: females choose between male mates - Intersexual selection: members of the same sex compete with each other in order to mate with others What determines. Who is more selective: - Female gamete size - Higher cost for females - Maternal care - Reproductive turnaround Direct vs. indirect benefit - Direct: food, protection, nest sites - Indirect: good genes for offspring Courtship competition: weapons, ornaments, displays Types of mating systems: - Monogamy: lifetime bond - Polygyny: one individual mates with multiple individuals o Female defense, resource defense, lek, scramble - Polyandry females mate with more than one male COMMUNICATION AND SOCIAL BEHAVIORS True communication: sender and receiver benefit Manipulation or deceit: sender benefits, receiver unaffected or harmed Eavesdropping or exploitation: sender if unaffected or harmed receiver benefits Why do animals communicate? - Spacing, recognition, reproduction, social status, alarm, finding food, soliciting care, play Methods of communications: chemical, auditory, visual, electrical, tactile Honey bee dance language: - Round dance: food within 80 m of hive - Waggle dance: food > 80m away, distance and direction by angling - Odor: on the bee’s body provides info about the kind of flower Types of species interactions: - Competition: o Interspecific: results in exclusion or coexistence Coexistence: resource partitioning o Predation, paratism, herbivory: one species benefits, other is harmed o Mutualism: both species benefit o Commensalism: one benefits, other is unaffected or harmed Costs of competition: energy demand is high, possible injury, time Benefits of competitions: increases survival and reproductive success, secure access to some limited resource, avoid overt aggression, interaction with neighbors are less frequent and intense Internal factors for competition: hormones, neural mechanisms, genetics Group living costs: increased competition for resources, exposure to parasites and disease, conspicuousness of groups to predators, interference with reproduction Group living benefits: anti-predatory effects, protection from physical factors, easier to find a mate and reproduce, resource defense, division of labor, richer learning environment Prey survival methods: colony living, mimicry, camouflage/cryptic coloration, physical defense Parasite: does not kill the host, benefiting from a relationship with the hose Parasitoid: organism whose immature life stages develop inside the host, usually killing it Kin selection: since an individual’s alleles are in other individuals besides the offspring, if family members have more offspring that reproduce representation of an individual will increase
