Textbook Notes (368,125)
Canada (161,663)
HMB265H1 (54)
Chapter

Summary of Week 1 - Readings and Lecture

5 Pages
151 Views
Unlock Document

Department
Human Biology
Course
HMB265H1
Professor
Stephen Wright
Semester
Fall

Description
Week 1 DNA – deoxyribonucleic acid Genetics: study of all aspects of genes Genes: fundamental units of biological info Genetics: 1. Molecular Genetics: works on few genes at a time 2. Genomics: study of the complete gene set (genome) Continuum of Genetic and Environmental Factors contributing to disease: it’s a gradient The Nature of Biological Information: - Chromosomes are hypothesized to hold information because they are passed down intact to a new generation through VERY PRECISE divisions. Diploid: two sets of the genome, 2 identical chromosome sets Ex: humans Haploid: one set (the haploid number is n = number of chromosomes in a set) Ex: fungi, bread mold Homologs/Homologous Chromosomes: - two identical chromosomes (paired in meiosis) – can be different alleles. - Not necessarily next to each other when not undergoing meiosis Introns: noncoding inserts in genes ** Gel Electrophoresis can separate DNA molecules Packing DNA: - DNA double-helix coils around a nucleosome Nucleosome: 8 histone proteins Chromatin: Nucleosomes and the DNA Centromere: constricted region acting as attachment point to move the chromosomes around Telomere: Tips of the chromosome – work like the aglet ** Mitochondria and Chloroplasts also have DNA Prokaryotes: - No nuclei - Genome is not bound - Single noncoiled chromosome in cytoplasm - Has plasmids (circular chromosomes) Proteins: 1. Structural: contribute to outward physical structure – hair, nails, muscles, cytoskeleton 2. Enzymatic: catalyze the reactions within the cells 3. Regulatory: turn gene activity on and off Transcription: - Stage I in protein synthesis - DNA is copied into RNA - RNA o Ribose sugar o Cytosine, Guanine, Adenine, and Uracil Nucleotides o Single linear strand o mRNA: removed introns, messenger o rRNA: ribosomal o tRNA: transfer – carry the amino acids in translation o can be reverse transcribed into DNA o Translation: - mRNA is translated into a polypeptide - 3 nucleotides make a codon - Codon: code for specific amino acid - A ribosome reads these codes and makes protein DNA Replication: - Helix is unzipped - Complementary strand formed - New strand is ligated Mutation: a mutation in egg or sperm cells can be passed down, a mutation in somatic cells either dies or grows into a tumor Epigenetic: nongenetic changes Natural Selection: - Homology: similarities due to common ancestry - Differences are due to natural selection (some individuals may produce more offspring) Constructing Evolutionary Lineages: - Branched diagram showing ancestry over time - Genetics show us that chimps are our closest living relatives - Race is not meaningful at the genetic level Forward Genetics: treat cells with normal genes with agents such as chemicals or radiation. Proceed by screening for mutants. Mutations will allow for the discovery of that gene’s function. Phenotype  Mutations  Gene for phenotype Reverse Genetics: A gene with no known function is taken and forced to mutate (or knockout), by studying the resultant effects, the function can be learned. Genotype  Mutations  gene function Manipulating DNA: 1. DNA Cloning: take DNA fragment, replicate and amplify 2. Modify DNA and reintroduce to organism or introduce to difference organism 3. Sequence the DNA Detecting Specific Sequences for DNA, RNA, and Protein: 1. Probing: used to detect specific macromolecules o Probe is labelled (radioactive or fluorescent) o Relies on specif
More Less

Related notes for HMB265H1

Log In


OR

Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


OR

By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.


Submit