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Grade 12 Biology Exam with correct
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CLONES - correct answer ✔ genetically identical organisms derived from a single genetic source POLYGENIC TRAITS - correct answer ✔ traits such as skin color, height which are controlled by many (poly) genes ASEXUAL REPRODUCTION - correct answer ✔ mode of reproduction where offspring arise from a single parent and inherits the genes of that parent only (2n → 2n) TELOMERES - correct answer ✔ the protective caps at the end of chromosomes SEX-LINKED TRAITS - correct answer ✔ traits that are carried on the X chromosome GAMETES - correct answer ✔ reproductive cells (i.e. egg and sperm) formed during meiosis (2n → n) GENES - correct answer ✔ controls the traits in an organism
CARRIERS - correct answer ✔ they can pass a gene for a recessive disorder; they are heterozygous for a recessive disorder; they have one dominant allele PYRIMIDINES - correct answer ✔ nitrogen bases in DNA; include thymine and cytosine ALLELES - correct answer ✔ an alternative form of a single gene passed from generation to generation ZYGOTE - correct answer ✔ part of sexual reproduction; result of the union of egg and sperm (2n) PURINES - correct answer ✔ nitrogen bases in DNA; include adenine and guanine CROSS POLLINATION - correct answer ✔ process Mendel used to pollinate flowers of short plants with pollen from tall plants (when pollen is delivered to a flower from a different plant) FERTILIZATION - correct answer ✔ the process by which haploid gametes combine → result is the formation of a zygote CROSSING OVER - correct answer ✔ exchange of genetic material between homologous chromosomes → results in genetic recombination (occurs in meiosis during prophase I) DIHYBRID - correct answer ✔ individual differing in two traits (i.e. BbEe)
GENE THERAPY - correct answer ✔ treating genetic disorders by inserting normal alleles into cells THEORY - correct answer ✔ series of statements that can explain multiple hypotheses; provides explanations and predictions that can be tested HAPLOID - correct answer ✔ cell with one of each kind of chromosome (sex cells) → n DIPLOID - correct answer ✔ two of each kind of chromosome (somatic cells ) → 2n• MENDEL'S LAW OF INDEPENDENT ASSORTMENT - correct answer ✔ In meiosis, the way in which a chromosome pair separates does not affect the way other pairs separate MENDEL'S LAW OF SEGREGATION - correct answer ✔ During meiosis, the factors that control each trait separate, and only one factor from each pair is/are passed to the offspring HETEROZYGOUS - correct answer ✔ when there are 2 different alleles for a trait (Rr) HOMOZYGOUS - correct answer ✔ when there are two identical alleles for a trait (RR or rr)
GENOTYPE - correct answer ✔ combination of genes in an organism (allele combinations) PHENOTYPE - correct answer ✔ outward appearance of an organism (physical appearance)• MITOSIS - correct answer ✔ cell division where 2 identical cells are produced (2n → 2n) MEIOSIS - correct answer ✔ cell division where one cell produces 4 haploid cells (2n → n) NOTE: this process ensures that the same diploid number as its parents after fertilization INCOMPLETE DOMINANCE - correct answer ✔ inheritance pattern where two dominant alleles produce a brand new trait when they are expressed together CO-DOMINANCE - correct answer ✔ inheritance pattern where two dominant alleles exist and are expressed together at the same time AUTOSOMAL CHROMOSOMES - correct answer ✔ 22 pairs of chromosomes (excluding the sex chromosomes) → somatic cells SEX CHROMOSOMES - correct answer ✔ 23rd pair of chromosomes in humans → determines sex of individual (XX - female, XY - male) DNA - correct answer ✔ double stranded, bases include: A,T,C,G and the sugar is deoxyribose
FUNCTION OF DNA LIGASE - correct answer ✔ a sealing enzyme PROMOTER - correct answer ✔ binds with RNA polymerase to initiate transcription MET-TRNA - correct answer ✔ called the initiation complex and is the start of polypeptide assembly RNA SPLICING - correct answer ✔ when introns from the primary transcript and the final "processed" mRNA is produced mRNA (messenger RNA) - correct answer ✔ carries genetic information from DNA in the nucleus to direct protein synthesis in the cytoplasm tRNA (transfer RNA) - correct answer ✔ transports amino acids to the ribosome rRNA (ribosomal RNA) - correct answer ✔ associates with protein to form the ribosome NONSENSE - correct answer ✔ may cause a premature termination of the mRNA because of the substitution, deletion, or addition or nucleotides that code for a "stop" codon MISSENSE - correct answer ✔ substitution of nucleotides that alters only one amino acid sequence (little or no effect on the polypeptide formation)
SILENT MUTATION - correct answer ✔ substitution of a nucleotide that codes for the same amino acid → no change in the formation of the polypeptide. TRANSLOCATION - correct answer ✔ one chromosome breaks off & is added to a different chromosome INVERSION - correct answer ✔ chromosome breaks off & is reinserted ADDITION - correct answer ✔ duplication of genes on the same chromosome (also called addition) DELETION - correct answer ✔ part of a chromosome is left out FRAMESHIFT MUTATION - correct answer ✔ single base is added/deleted. One of the most severe types ofmutations POINT MUTATION - correct answer ✔ change in a single base pair of DNA EVOLUTION - correct answer ✔ changes over many generations FITNESS - correct answer ✔ is a measure of the contribution of a genotype to the gene pool of the next generation MICROEVOLUTION - correct answer ✔ changes in gene frequencies within a population
SPECIATION - correct answer ✔ evolution that results in a new biological species PROKARYOTE - correct answer ✔ unicellular organism that lacks a nucleus EXTREMOPHILE - correct answer ✔ form of archaebacterial; can live in extreme environments ENDOSYMBIONT THEORY - correct answer ✔ theory that suggests the important relationship between ancestral eukaryotic and prokaryotic cells DERIVED TRAITS - correct answer ✔ recently evolved traits that do not appear in ancestral fossils TAXONOMY - correct answer ✔ the identification, naming, and classifying of species PHYLOGENY - correct answer ✔ the evolutionary history of a species TAXON - correct answer ✔ a group of organisms at any particular level in a classification system TWO MAIN POINTS OF NATURAL SELECTION - correct answer ✔ variation and inheritance lead to evolution CONVERGENT EVOLUTION - correct answer ✔ different species exhibit adaptations as a result of the same environment (i.e. flippers of seals and
penguins - the seal is a mammal and the penguin is a bird → different species; structures have evolved in these different species because it was the best functional feature for their environment) NATURAL SELECTION - correct answer ✔ an inherited characteristic enables the organism to survive in a given environment (i.e. Peppered moths in England after industrial pollution → dark wings were favored and increased its population in the gene pool) SPECIATION AND ISOLATION - correct answer ✔ a single population divides into two reproductively isolated populations or equivalent (use of gene pools), role of barriers in speciation or discuss gene pool separation or link to natural selection (i.e. Abert squirrel and Kaibab squirrel living near the grand canyon - the geographical barrier has caused evolutionary changes within each organism) HOMOLOGOUS STRUCTURE - correct answer ✔ structures with the same embryological origin and structure → different function (i.e. forelimbs of a horse and a human) ; a way that scientists use genetics to determine evolutionary relationships ANALOGOUS STRUCTURE - correct answer ✔ structures with no common embryological origin → have similar function (i.e. wings of hawks and beetles); is not a way that scientists use genetics to determine evolutionary relationships PHYLOGENY - correct answer ✔ evolutionary history of a species (relationships) CLADISTICS - correct answer ✔ method used to construct a hypothetical evolutionary tree (assuming groups of organisms diverge and evolve from a common ancestor)
PUNCTUATED EQUILIBRIUM - correct answer ✔ model of evolution that states that evolution occurs rapidly ANGIOSPERMS - correct answer ✔ flowering plants GYMNOSPERMS - correct answer ✔ referred to as "naked-seed" plants VESTIGIAL ORGAN - correct answer ✔ reduced form of a functional structure that indicates shared ancestry (i.e. appendix in humans) MIGRATION - correct answer ✔ the movement of genes into and out of a gene pool (most likely to contribute to gene flow between populations) STABILIZING SELECTION - correct answer ✔ the average individuals of a population are favored. i.e. Human babies born with below-normal and above- normal weights have a lower chances of survival than babies born with average weights (birth weights don't vary much in human populations) DIRECTIONAL SELECTION - correct answer ✔ selection that favors one extreme form of a trait in a population. i.e. Dark colored peppered moths favored on the bark of oak trees after industrial pollution DISRUPTIVE SELECTION - correct answer ✔ favors both extreme forms of a trait. i.e. A plant with three varying heights have their own pollinators - when the pollinator that prefers the plant of medium height leaves an area, medium height plants would be selected against and their populations would decline
OVER-EXPLOITATION - correct answer ✔ the excessive use of species that have economic value (i.e. Bison - hunted for meat and hide that could be sold commercially - hunted for sport to the brink of extinction) EDGE EFFECTS - correct answer ✔ conditions near the boundary between two habitats SUSTAINABLE USE - correct answer ✔ using resources at a rate in which they can be replaced ECOLOGICAL SUCCESSION - correct answer ✔ The change in one ecosystem that happens when one community replaces another as a result of changing abiotic and biotic factors BIOTIC - correct answer ✔ living factors (i.e. plants, animals) PUBLIC EDUCATION - correct answer ✔ making all members of society aware of possible impacts of their actions and decisions BIOREMEDIATION - correct answer ✔ addition of living organisms (natural predators) to a degraded ecosystem ABIOTIC - correct answer ✔ non-living factors (i.e. sunlight, water) RENEWABLE RESOURCE - correct answer ✔ resources that can regenerate (i.e. solar energy, wind)
EXTIRPATED SPECIES - correct answer ✔ any species, once native to Manitoba, which has disappeared through all of its Manitoba range ENDANGERED SPECIES - correct answer ✔ any native Manitoba species threatened to disappear through all or most of its Manitoba range THREATENED SPECIES - correct answer ✔ any native Manitoba species likely to become endangered or at risk due to low or declining numbers in Manitoba, if the factors affecting it don't improve VULNERABLE SPECIES - correct answer ✔ species not regulated under the Endangered Species Act, but which could be considered endangered or threatened if the factors affecting them do not improve LEVELS OF BIOLOGICAL ORGANIZATION - correct answer ✔ atoms, molecules, cells, tissues, organs, organ systems, organism ATOMS - correct answer ✔ smallest particle of any element MOLECULES - correct answer ✔ atoms that are joined together CELLS - correct answer ✔ smallest unit of life; differ in size, shape, and function TISSUES - correct answer ✔ group of cells with similar functions
ORGANS - correct answer ✔ make up the various organ systems - composed of different tissues ORGAN SYSTEMS - correct answer ✔ composed of various organs that perform functions that keep an organism alive and well ORGANISM/INDIVIDUAL - correct answer ✔ collection of organ systems INTERPHASE - correct answer ✔ which consists of G1(cell growth, increase in size, synthesis of proteins, production of organelles), S (replication of the genome occurs in nucleus), and G2(takes inventory and makes sure it is ready for the division of the nucleus; growth and preparation), majority of its life MITOSIS - correct answer ✔ the process of the cell cycle where the nucleus divides to create two identical nuclei (includes stages: prophase, metaphase, anaphase, telophase) CYTOKINESIS - correct answer ✔ division of the cytoplasm → 2 new cells (NOTE: in plant cells, a cell plate forms instead of the cytoplasm dividing) INTERPHASE - correct answer ✔ cells grows, DNA synthesized & replicated, cell prepares for division PROPHASE - correct answer ✔ chromatin coils to form visible chromosomes METAPHASE - correct answer ✔ chromosomes move to the equator
•The mRNA binding site is on the small subunit •There are three tRNA binding sites: A site, P site, and E site •Site where polypeptide chain is created and released PCR (Polymerase Chain Reaction) - correct answer ✔ function is to copy gene sequences (amplify DNA) STEPS:
- DENATURATION - (94°C) DNA separates
- ANNEALING - (54°C) Primers bind to single DNA strands
- EXTENSION - (72°C) DNA polymerase (Taq polymerase) adds bases to the primer segments to build up complementary strands of DNA DARWINS VOYAGE - correct answer ✔ Spent 5 years sailing on the H.M.S Beagle
- observations were that the species of organisms on the Galapagos islands differed from those organisms on the mainland. Published "On the Origin of Species by Means of Natural Selection" HARDY WEINBERG CONDITIONS - correct answer ✔ • Large population •No immigration or emigration (migration= movement in an out) •No mutation in the gene of interest •No natural selection occurs (individuals reproduce at equal rates) •Mating is random HARDY WEINBERG FORMULA - correct answer ✔ p^2 (homozygous dominant individuals)+2pq (heterozygous dominant individuals)+ q^2 (homozygous recessive individuals)=1(total population)
CLASSIFOCATION SYSTEM - correct answer ✔ Kingdom (least specific - broadest category) Phylum Class Order Family Genus Species (most specific - smallest category) DOMAIN - correct answer ✔ created because of great differences among bacteria EUBACTERIA VS ARCHAEBACTERIA - correct answer ✔ Eubacteria have peptidoglycan in their cell walls BACTERIA SHAPES - correct answer ✔ • Bacilli - rod •Cocci - spherical •Spirochetes - spiral BINARY FISSION - correct answer ✔ • Asexual •Steps:
- DNA replicates
- Cell elongates
- Divides into 2 genetically identical cells
