Intro to Genetics - Week 1

first week of BIO 2235

William Harvey

Theory of Epigenesis: structures such as body organs are not initially present in the early embryo and are formed later

Schleiden and Schwann

The Cell Theory (1830): all organisms are composed of basic structural units called cells

On the Origin of Species (1859)

Published by Charles Darwin and introduced the theory of Natural Selection.

Variation and Inheritance

in 1866, Mendel published his findings where traits are passed from generation to generation and the transmission of genetic information is from parents to offspring

mitosis

Cell division resulting in two identical daughter cells that receive a diploid set

Diploid number

2n

Meosis

the process by which the number of chromosomes is reduced by half to form sex cells

Haploid number

1n

Genes are transmitted through

gametes

Alleles

different versions of a gene; source of genetic variation

Mutations produce what?

alleles of a gene

genotype

the set of alleles for a given trait

phenotype

expression of genotype

Frederick Griffith

Discovered transformation during an experiment that involved injecting mice with smooth S cells, rough R cells, heat-killed S cells, and heat-killed S cells with living R cells.

Oswald Avery, Colin MacLeod, and Maclyn McCarty

Expounded upon Frederick Griffith's Streptococcus pneumoniae experiment, removing all but one of the macromolecules in each determination. Found that DNA was molecule of heritability.

DNA

antiparallel, double-stranded helix, made of nucleotides

monomer

nucleotide consisting of a sugar (deoxyribose), bonded to a phosphate, also bonded to A, C, G, and T

RNA

single-stranded, uses U instead of T, the sugar is ribose

Central Dogma

DNA -> RNA -> Protein (the sequence of transfer of information in organisms)

genetic code

the genetic information held in DNA, written in codons translated into amino acid sequences

transgenic organism

Organisms that contain functional recombinant DNA from a different organism

restriction enzymes

Enzyme that cuts DNA at a specific sequence of nucleotides

Biotechnology

A form of technology that uses living organisms, usually genes, to modify products, to make or modify plants and animals, or to develop other microorganisms for specific purposes.

Genomics

Studies the structure, function, and evolution of genes and genomes

Proteomics

identifies the set of proteins present in a cell under a given set of conditions, and studies their functions and interactions

Bioinformatics

use of computer databases to organize and analyze biological data

common origin

Darwin's claim that similar living species must all have had a common ancestor

forward genetics

Approach used to identify a gene controlling a phenotypic trait in the absence of knowledge of a gene's location or its DNA sequence.

reverse genetics

DNA sequence of a particular gene of interest (GOI) is known, but its function is not and compare sequence to other organisms with known functions

model organism characteristics

easy to grow, short life cycle, produce many offspring, genetic analysis is straightforward

Modern model organisms

Viruses: T phages and lambda phages

Bacteria: Escherichia coli

Yeast: Saccharomyces cerevisiae

DNA cutting enzymes that cleave or "digest" DNA at specific sequences

restriction enzymes

chromosomes that synapse or pair during meiosis and that are identical with respect to their genetic loci and centromere placement

homologous chromosomes

the observable features of an organism

phenotype

recognize the information encoded in the mRNA codon and carry the proper amino acids for construction of the protein during translation

transfer RNA (tRNA)

organism develops from the fertilized egg by succession of developmental events that eventually transform the egg into an adult

epigenesis

The act of making a targeted gene nonfunctional in a model organism or in cultured cells to study the resulting phenotype.

gene knockout

translation

synthesis of proteins under the direction of mRNA

natural selection

The idea that populations tend to contain more offspring thanthe environment can support, leading to a struggle for survival among individuals.

nucleotide

nitrogenous base, sugar, phosphate

cell theory

All organisms are composed of basic structural units called cells, which are derived from preexxisting cells

genomics

Study of the structure, function, and evolution of genes and genomes

model organism

An organism used fo the study of basic biological processes

preformation

the fertilized egg contains a complete miniature adult

Messenger RNA (mRNA)

RNA molecule trancribed from DNA and translated into the amino acid sequence of polypeptide

proteomics

identifies the set of proteins present in a cell under a given set of conditions, and studies their functions and interactions

vectors

in recombinant DNA, an agent such as a phage or plasmid into which foreign DNA segment will be inserted and used to transform host cells

chromosome theory of inheritance

Inherited traits are controlled by genes residing on chromosomes faithfully transmitted through gametes, maintaining genetic continuity from generation to generation

Homunculus

miniature adult

genome

the complete haploid DNA content of a specific organism

transgenic

Transfer of heritable traits across species using recombinant DNA technology

Enzymes

Molecules that serve as biological catalyst by lowering the energy of activiation in reactions

Transcription

Nucleotide sequence in one strand of DNA is used to construct a complementary RNA sequence

Mutation

The process that creates an alteration in DNA or chromosome structure; in genes, the source of new alleles