Bio Exam Review 2024 PDF

Bio Exam Review 2024 Multiple Choice: ​ Unit 1 Binomial Nomenclature: first part of name is the genus, 2nd part is the species name. Italicized when typed, underlined when written. Viruses -​ contains DNA or RNA surrounded by a protein coat (the capsid)...

Bio Exam Review 2024 Multiple Choice: ​ Unit 1 Binomial Nomenclature: first part of name is the genus, 2nd part is the species name. Italicized when typed, underlined when written. Viruses -​ contains DNA or RNA surrounded by a protein coat (the capsid) -​ one method used to classify viruses is by the size & shape of the capsid -​ cannot survive on their own, need a host cell -​ cannot reproduce, only replicates -​ no nucleus, no cellular structures K. Fungi Structure -​ threadlike filaments (hyphae) -​ hyphae elongate & branch off to make a network (mycelium) -​ reproductive sys. Located above ground (fruiting body) -​ use spores to reproduce -​ cell walls made of ???? K. Bacteria -​ prokaryotic, unicellular, both autotrophic (make their own food) and heterotrophic (consume food from another source), asexual reproduction -​ typically have cell walls, can be anaerobic or aerobic K. Archaea -​ prokaryotic, unicellular, cell wall is not peptidoglycan, autotrophic and heterotrophic, asexual reproduction -​ more archaea live in extreme environments, typically have cell walls anaerobic respiration: doesn’t use oxygen aerobic respiration: uses oxygen ​ Cell Organelles - Function Nucleus: control center of cell, contains genetic material (DNA), surrounded by nuclear membrane Nucleolus: produces ribosomes, dense spherical structure in nucleus Nuclear Membrane: surrounds & protects nucleus, has pores that help control what enters/exits Centrosome: protects microtubules, involved in all cell division Cell Membrane: layer of fats that keep internal/external cell environment separated, semi-permeable, allow some substances in/out of cell depending on cell’s needs Golgi Body: use vesicles as packaging at edge of Golgi body, packaging of macromolecules for transport around/out of cell Mitochondria: produces energy (ATP), uses oxygen and glucose in the process of aerobic cellular respiration Vacuole: plays a role in intracellular digestion, release of cellular waste products, nutrient/waste storage, transportation, etc  Cytosol: where metabolism and other specialized functions occur Rough endoplasmic reticulum: ribosomes on exterior, as ribosomes produce proteins, they are pushed inside the RER for processing smooth endoplasmic reticulum: many different functions depending on type of cell Lysosome: contains enzymes to assist in digestion, breakdown and recycling of old cells, engulf bacteria and viruses, destroy cells Peroxisome: various functions, in plants they assist chloroplasts in photorespiration Ribosome: synthesize proteins, made from RNA, site of protein synthesis Cytoskeleton: various tubules that helps maintain structure of cell, help move organelles around the cell Flagella: aid the cell in moving one way or another Cilia: short hair like structures on outside of cell aid in transport Homologous Structures -​ chromosome that contains the same sequence of genes as another chromosome -​ may appear identical, but can carry different forms of the same genes at the same location Kingdom Animalia -​ radial symmetry: any longitudinal cut thru the midpoint yields equal halves -​ bilateral symmetry: only one longitudinal cut thru the midpoint yields equal halves (humans) -​ asymmetry: any way it is split, it is not identical ​ Unit 2 ​ Cell Cycle -​ made of interphase (G1, S, & G2 phases) and Cell Division (divided into mitosis and cytokinesis) -​ ensures the parent cell provides an identical set of chromosomes in each of its daughter cells -​ interphase purpose: grow cells, replicate dna, preparing cells for division -​ mitosis purpose: cell divides the nucleus and distributes DNA into 2 identical daughter cells -​ cytokinesis purpose: cytoplasm and organelles are divided between the daughter cells Phenotype: physical trait that is expressed in an organism Genotype: combination of 2 alleles for any given trait of an organism Allele: different form of same gene ( green vs brown eyes ) Homozygous: organism with 2 identical alleles of a gene Heterozygous: organism with 2 different alleles of a gene Zygote: fusion of special male and female reproductive cells called gametes, which then form into the zygote Somatic cell: human somatic cells have 46 chromosomes that are organized into 23 pairs, a plant or animal cell that forms the body of the organism sex chromosome: an X or Y chromosome, which determines the genetic sex of an organism gamete: male or female reproductive cell  autosome: a chromosome that is not involved in determine the sex of an organism monosomy: loss of a chromosome as a result of non-disjunction trisomy: gain of an extra chromosome as a result of non-disjunction n haploid: single cells with unpaired chromosomes are said to be haploid, the haploid # in a species is designated as n 2n diploid: cells that contain pairs of chromosomes (including all somatic cells) villi: tiny hair like filaments that line the entire length of the small intestine Multiple Alleles: Blood Type -​ in humans, 3 alleles for the same gene related to blood type -​ these alleles determine the presence or absence of antigens (proteins) on the surface red blood cells -​ gene is designated I/i, has 3 common alleles -​ IA reps the A allele -​ IB reps the B allele -​ i reps the O allele -​ alleles A and B are dominant over O, but A and B are codominant ​ Genotypes Type B: IBIB, IBi Type A: IAIA, IAi Type O: ii Type AB: IAIB -​ immune system attacks blood that contains the wrong antigens -​ blood types identified as positive or negative indicate whether blood has a protein (Rh factor) positive has it, negative does not Unit 3 Blood Components -​ plasma (~55%), red blood cells (~44%), white blood cells and platelets (~1%) -​ Plasma: clear, yellowish fluid made up of water & dissolved proteins, carries other substances -​ RBC’s: have no nucleus. Each contain ~280 million molecules of hemoglobin, which bind & transport oxygen in the blood -​ WBC’s: fight infection by destroying pathogens, have a nucleus -​ Platelets: fragments of cells, play a key role in blood clotting Pepsin -​ origin: stomach, where it acts & pH: stomach, 1-2, nutrient molecule digested: protein, products of digestion: peptides ​ Lipase -​ Origin: pancreas, where it acts & pH: small intestine, 8, nutrient molecule digested: lipids, products of digestion: fatty acids and glycerol  Amylase salivary: origin: salivary glands, where it acts & pH: mouth, 7, nutrient molecule digested: starch, glycogen, products of digestion: maltose (disaccharide) Pancreatic: origin: pancreas, where it acts and pH: small intestine, 8, nutrient molecule digested: starch, glycogen, products of digestion: maltose Accessory Organs -​ secretions from liver & pancreas help digestion -​ liver produces bile, stored in the gallbladder (bile breaks down fat into smaller fat droplets) -​ pancreas produces enzymes and bicarbonate (bicarbonate raises the pH level so enzymes can function efficiently) Respiration 1.​ contractions -​ intercostal muscles contract, diaphragm contracts, rib cage moves up and out, diaphragm moves down 2.​ volume and pressure in chest cavity -​ volume of chest cavity increases, pressure in chest cavity decreases 3.​ volume and pressure in lungs -​ walls of lungs drawn outward, lungs expand -​ increase volume, decrease pressure in lungs 4.​ air… -​ low pressure in lungs, high pressure in external environment -​ air rushes into lungs structures & order: nostrils and nasal cavity, inside the nasal cavity, thru the upper respiratory tract, to the lower respiratory tract, alveoli -​ air moves from external environment thru nostrils in nasal cavity -​ nasal cavity contains turbinate bones, covered by a thin membrane that secretes mucus (moistens air) -​ contains many blood vessels that warm air before it hits the lungs -​ air travels thru the pharynx then reaches the glottis -​ once air passes the glottis it enters the trachea, then enters the bronchi -​ air then enters the alveoli in the bronchi subunits of protein: amino acids subunits of lipids: fatty acids and glycerol overall enzyme purpose: specialize in breaking down one type of molecule Enzyme origin of enz. where it acts/pH nutrient molecule products of digested digestion salivary amylase salivary glands mouth/7 starch, glycogen maltose carbohydrates small intestine small intestine/8 sucrose, maltose, glucose, (sucrose, lactose fructose, maltase, galactose lactase) pancreatic pancreas small intestine/8 lipids fatty acids, lipase glycerol proteases pepsin stomach stomach/1-2 protein peptides trypsin pancreas small intestine/8 small polypeptides smaller chymotrypsin pancreas small intestine/8 small polypeptides peptides smaller peptides pancreatic pancreas small intestine/8 starch, glycogen amylase peptidases pancreas, small small intestine/8 peptides intestine Unit 4 Root Structures & Functions Roots: anchor the plant, absorb water & nutrients, store carbs Root Tips: contain meristematic cells, consist of parenchyma cells that protect growing tissue, secret slimy substance to reduce friction Outer Root Layers: root is covered by layer of dermal tissue, btwn the cortex and vascular tissue is the endodermis, each cell in it surrounded by the casparian strip Casparian Strip: barrier that forces water & dissolved minerals to cross the cell membrane and pass thru the cytoplasm Plant Tissues -​ Meristematic: undifferentiated, embryonic tissue found in areas of rapidly dividing cells -​ Dermal: made up of epidermal cells and other specialized cells, covers exterior of plant -​ Epidermis: protects entire body of non woody plants & young woody plants -​ Guard Cells: control opening size of stoma -​ Trichomes: tiny hairs that reduce evaporation, some secrete toxic substances -​ Root Hairs: increase surface area for water & nutrient absorption  -​ Ground: form most of a plants interior/exterior material, involved with photosynthesis, storage & support -​ Vascular: transport materials, divided into xylem and phloem, connects roots to leaves, arranged in bundles in non woody flowering plants Monocots: xylem cells form a ring around central core of cells, phloem cells ​ surround Xylem cells in this ring Dicots: xylem cells form an X or star shape, phloem cells are btwn the arms of the star Plant Hormones Auxins stimulate cell division in stems & roots. Control a plant’s response to light & gravity. Cytokinins produce proteins used for cell division, promote rapid growth, prevent aging of leaves & fruit. Ethylene promotes ripening of fruit by weakening cell walls of unripe fruits, breaks down carbohydrates into simple sugars. Gibberellins stimulate cell elongation in shoots to promote stronger, taller plants. They “break” dormancy cycles in seeds & buds. Abscisic Acid keeps seed dormant, inhibits shoot & leaf growth, closes stomata, blocks action of other hormones. Parts of the Flower and their Functions sepal: protect flower bud Petal: attract pollinators Anther in stamen (M): produce pollen, contain sperm Pistil (F): F gametophytes in ovaries develop here Stigma (F): where fertilization takes place Unit 5 Fitness: relative contribution an individual makes to the next generation by producing offspring that will survive long enough to reproduce selective advantage: genetic advantage that improves an organism’s chance of survival, usually in a changing environment gene flow: net movement of alleles from one population to another due to the migration of individuals. occurs btwn 2 different interbreeding populations with different allele frequencies evolution: process of genetic change in a population over time founder effect: change in a gene pool that occurs when a few individuals start a new isolated population, small # of individuals into a new area. bottleneck effect: changes in gene distribution that result from a rapid decrease in population size. surviving organisms begin to grow the population but with a smaller gene pool. genetic drift: change in frequencies of alleles due to chance events in a breeding population. random change in genetic variation from generation to generation due to chance. macroevolution: large scale evolutionary changes that occur over long periods of time  species: group of organisms that can reproduce with one another in nature and produce fertile offspring Short Answer: unit 1 Taxonomy hierarchy 1.​ domain 2.​ kingdom 3.​ phylum 4.​ class 5.​ order 6.​ family 7.​ genus 8.​ species Eukaryotic cells: membrane bound organelles, aerobic respiration, can reproduce both asexually and sexually Prokaryotic cells: contain ribosome, no membrane bound organelles, anaerobic respiration, their DNA is a single loop of double stranded DNA, asexual reproduction, cell division by binary fission k. protista (junk drawer) -​ wildly different from each other -​ both unicellular and multicellular -​ some photo synthesize if they have green chlorophyll filaments -​ can be autotrophic or heterotrophic -​ can reproduce asexually and sexually unit 2 mitosis -​ a cell’s copied genetic material separates and the cell prepares to split into 2 daughter cells -​ enables the cell’s genetic information to pass into the new cells prophase -​ chromatin condenses into chromosomes -​ each chromosome is made up of 2 identical sister chromatids joined at the centromere -​ nuclear membrane breaks down, nucleolus disappears -​ spindle fibres form from the centromeres ​ metaphase -​ spindle fibres guide chromosomes to the equator (center of cell) -​ spindle fibres attach to the centromere of each chromosome anaphase -​ each centromere splits apart, sister chromatids separate from each other -​ chromatids now referred to as chromosomes -​ spindle fibres pull chromosomes to opposite poles of cell  telophase -​ nuclear membrane reappears, two daughter cells form codominance: when both alleles are expressed (cow is a heterozygote with both vase colour and white colour visible) Meiosis Purpose: produces gametes for sexual reproduction, reduces chromosome number by half. Phases: meiosis I - homologous chromosomes separate (Prophase I, Metaphase I, Anaphase I, Telophase I), meiosis II - sister chromatids separate (Prophase II, Metaphase II, Anaphase II, Telophase II) describe what happens during each phase Gametogenesis: formation of sperm (spermatogenesis) and eggs (oogenesis) End Products: four haploid cells unit 3 circulatory system functions -​ transports materials within the body -​ supports respiratory sys. (transporting oxygen to cells) and digestive sys. (transports nutrients to cells, eliminates waste) -​ helps regulate the body’s temperature -​ protects against blood loss and infection arteries -​ carry blood away from heart, walls have thick muscles to help move blood -​ most of them carry oxygenated blood to the tissues & organs of the body -​ small arteries: arterioles ​ veins -​ carry blood to the heart, less muscle in their walls, have valves to prevent blood from flowing backward -​ muscles surrounding the veins help keep blood moving forward -​ most of these carry deoxygenated blood to the heart -​ small veins: venules capillaries -​ one cell thick, where nutrients, gases, waste diffuse btwn the circ. sys. and body cells -​ arterioles connect to one end while venules connect to the other end how body regulates temperature vasodilation: blood vessels widen, increases blood flow, helps the body cool down by releasing heat vasoconstriction: blood vessels narrow, reduces blood flow, conserves heat to keep body warm -​ both processes controlled by nervous system to help maintain homeostasis unit 4 Leaf Structures & Functions -​ blade of simple leaf not divided into smaller parts, blades of compound leaves divided into smaller leaflets -​ a leaf’s venation is the pattern of the veins in the leaf -​ parallel: veins run parallel to the main vein and each other -​ pinnate: veins branch off along the central vein -​ palmate: veins branch off from a common point (maple leaf) -​ opposite growth: 2 leaves attached to the stem directly opposite each other at the same level -​ alternate growth: leaves arranged in a step-like pattern on either side of the stem, each leaf at a different level -​ whorled arrangement: 3 or more leaves evenly spaced around a stem at same level Specialized Plant Cells Parenchyma Form: flexible, thin walled, spherical Function: storage, photosynthesis, gas exchange, protection, tissue repair and replacement Collenchyma Form: elongated (celery string), unevenly thick walls, flexible Function: support for surrounding cells, flexibility, tissue repair and replacement Sclerenchyma Form: very thick, tough secondary cell walls (apple core) Function: support for mature plants - most de once developed, losing their cytoplasm but retaining cell walls Balanced photosynthesis equation: CO2+H2O—>C6H12O6+O2 Xylem -​ transports water from roots to leaves, made from tracheids in gymnosperms, made from tracheids & vessel element cells in angiosperms -​ fluids pass from one tracheid/vessel to the next thru the pits -​ when they mature, cell contents die, cell wall stays in place ​ Phloem -​ transports nutrients from leaves to rest of plant, can move up or down (or both at same time) on the plant -​ composed of sieve tube elements (alive at maturity, no nucleus) and companion cells (have nuclei, keep STE alive) Tropisms -​ a stimulus causing a plant to grow toward/away from it -​ positive is growth towards stimulus -​ negative is growth away from stimulus  Phototropism: growth response to light stimulus (unequal distribution of hormone auxin - less auxin on the side of the plant towards the light, more on the side away from light, causing it to curve) -​ this causes cell elongation, stem: positively phototrophic, roots: negatively phototrophic Gravitropism: describes a response to gravity using auxins. -​ roots exhibit positive grav. (towards gravity/down) to anchor the plant and brings roots to the water & nutrients -​ stems exhibit negative grav. (away/up) to get most access to the light Thigmotropism: growth response to mechanical stimuli (contact with object or another organism, wind) due to an unequal distribution of auxin. Nastic Response: flower that closes its petals at night and opens them during the day exhibits this. A reversible response to a stimulus that is not associated with the direction of the stimulus. Meristems Apical: at tips of roots and stems, cause growth in length (primary growth) Lateral: allow stems, trunks, and bark to become thicker as plant grows taller (secondary growth) unit 5 variation: differences between individuals, may be structural, functional, or physiological selective pressure: environmental conditions that select for certain characteristics of individuals and select against other characteristics artificial selection: selective pressure exerted by humans or populations in order to improve or modify particular desirable traits natural selection: process by which characteristics of a population never change over many generations as organisms with heritable traits survive and reproduce, passing their traits on to offspring allopatric speciation: speciation in which a population is split into 2 or more isolated groups by a geographic barrier -​ isolation prevents gene flow, leading to divergence and formation of new species sympatric speciation: speciation in which populations within the same geographic region diverge and become reproductively isolated -​ often results from ecological isolation, behavioural differences, or polyploidy in plants Theories of Lamarck and Darwin Lamarck -​ proposed that organisms change during their lifetime by using or not using certain body parts -​ suggested that acquired traits could be inherited by offspring (ex: giraffes stretching their necks to reach higher leaves) -​ theory was later disproved but introduced the idea that organisms adapt to their environments ​ Darwin -​ developed the theory of evolution by natural selection -​ key concepts: variation exists among individuals in a population, struggle for existence leads to survival of the fittest, favorable traits become more common over generations -​ published On the Origin of Species in 1859