



Study with the several resources on Docsity
Earn points by helping other students or get them with a premium plan
Prepare for your exams
Study with the several resources on Docsity
Earn points to download
Earn points by helping other students or get them with a premium plan
Community
Ask the community for help and clear up your study doubts
Discover the best universities in your country according to Docsity users
Free resources
Download our free guides on studying techniques, anxiety management strategies, and thesis advice from Docsity tutors
BIOD 101 Module 4 Exam Portage learning Questions with Verified Answers 2025 Update
Typology: Exams
1 / 5
This page cannot be seen from the preview
Don't miss anything!
Nitrogenous bases of DNA - Adenine Guanine Thymine Cytosine Contain 2 carbon-nitrogen rings, and 4 nitrogen atoms - Purines - A and G Contain 1 carbon-nitrogen ring, and 2 nitrogen atoms - Pyramidines - T and C Deoxyribose - sugar chemically linked to each base in DNA Nucleoside - base + deoxyribose Nucleotide - base + deoxyribose + phosphate group complementary pairs - purine always pairs with pyramidine (T+A), (C+G) Occur when 2 negatively charged atoms share a hydrogen atom - Hydrogen bonds
sequence - specified linear arrangement of nucleotides linked to the polynucleotide chains of DNA. Defines the entire organism end terminating with a phosphate group - 5' (five prime) end end terminating with a hydroxyl group - 3' (three prime) end antiparallel arrangement - one side of the helix runs in the opposite (5'-3') direction of the other (3'-5) Genome - entire sequence of paired bases in DNA histone proteins - A simple protein bound to DNA, involved in the coiling of chromosomes Chromatin - DNA sequences and their associated proteins Chromosomes - structures of packaged chromatin complexes Somatic cell - All of the body's cells except gametes Number of chromosomes in each somatic cell - 46 (23 pairs) Cell cycle - Process of parent cell replicating its genetic info and dividing into 2 new daughter cells
cytokinesis - division of the cytoplasm interphase - G1, S, G2 phases. 90% of cycle time. Gap phase 1 - First phase, growth phase Messenger RNA (mRNA) - transfers genetic info from DNA to ribosomes site of protein synthesis - ribosomes S phase - DNA duplication phase, lasts 10 - 12 hours G2 phase - Second growth phase, when synthesis of organelles and proteins needed for mitosis occurs. Lasts 4 - 6 hours. centrosome - region that organizes microtubules for cell division centriole - short cylindrical protein filaments made of tubulin. Plays role in formation of mitotic spindle. Chromatin fibers become more coiled and densely packed, sister chromatids are joined at the centromere and have an X shape. - Condensation stage of prophase Cohesions - proteins holding sister chromatids together Microtubules begin moving to opposite poles of cell - Centrosome movement stage of prophase aster - Radial microtubule proteins extending from each centrosome Cytoskeletal apparatus composed of different types of microtubules to separate sister chromatids. Includes centrosomes, spindle microtubules, and asters - Mitotic spindle Synthesizes ribosomal subunits, breaks down during prophase - Nucleolus Characteristics of Prophase - 1. Condensation of chromatin fibers
gametes - sperm and egg cells diploid - cells with 46 chromosomes, 2 from each parent meiosis - process that reduces gametes to a haploid state autosomes - all chromosomes except sex chromosomes homologs/homologous chromosomes - contain the same genes for inherited characteristics, are same size and have same location of centromeres karyotype - ordered display of homologous chromosomes Meiosis I - process of separation of homologous chromosomes Meiosis II - process of separation of sister chromatids crossing-over - the exchange of genes between homologous chromosomes, resulting in a mixture of parental characteristics in offspring. cohesins - cohesion proteins pairing together sister chromatids synaptonemal complex - zipper-like protein complex bringing non-sister chromatids together into synapsis chiasmata - crossing over points between sister chromatids recombinant chromosomes - distinct chromosomes created by crossover, carrying genetic info from both parents but not identical to parents Metaphase I - Difference from mitosis is that both chromatids of one homolog (maternal) are attached and line up to both chromatids of other homolog (paternal) to one kinetochore along plate Anaphase I - Difference is sister chromatids remain attached at centromere. Chromatid pair is getting pulled toward its centrosome pole. Telophase I and cytokinesis - Difference is nuclear envelope and nucleoli do not reassemble yet. Cell is haploid but must be reduced Non-disjunction - failure of sister chromatids to separate properly Trisomy 21 - Carrying an extra copy of chromosome 21; also known as Down syndrome. True breeding plants - will continue to display characteristics of parent plant over several generations of offspring hybridization - crossing two true-breeding plants Alleles - Different versions of the same gene. ex: eye color and blood type Locus - location of alleles (one from each parent) on a chromosome dominant allele - occurs more frequently recessive allele - is present but has no observable effect on appearance
Law of Segregation - alleles for different traits become separated during gamete formation (meiosis) Homozygous - when an organism has the same alleles for a particular trait. ex: PP Heterozygous - when an organism has different alleles for a particular trait. ex: Pp Genotype - An organism's genetic makeup, or allele combinations (homozygous vs. heterozygous) Phenotype - An organism's physical appearance, or visible traits. monohybrid cross - when only a single trait is studied during a cross dihybrid cross - A cross between two individuals, concentrating on two definable traits dihybridization - when two traits from true-breeding parents are followed in F2 generation to see if traits will be inherited together or separately law of independent assortment - two or more genes are independent of each other Ratio of independent assortment in F2 (4 sperm x 4 eggs) - 9:3:3: complete dominance - when phenotype for a dominant trait is exhibited regardless of genotype incomplete dominance - when offspring have different phenotypes than parents codominance - when traits for both alleles are expressed in the phenotype pleiotropy - when one gene has multiple phenotypic effects CFTR gene - a gene that codes for a protein involved in chloride and water transport across membranes. In patients with cystic fibrosis, a mutation in this gene disrupts chloride and water transport across membranes. The end result is production of thick and sticky mucus that obstructs the airways in the lungs and the ducts in the pancreas.