Upgrade to remove ads
Genetics Chapter 1- Genetics: An Introduction
Russell, Peter J. (2011-04-14). iGenetics: A Molecular Approach (3rd Edition). Pearson HE, Inc.. Kindle Edition. Key terms from the eTextbook and Study Guide Introductory Genetics Course at SHSU Spring 2015 Prof.: Dr. Choudhary
Terms in this set (89)
An early model for genetic variation that
was based on the assumption that most natural populations had a wild-type allele with very few mutant alleles present.
principles of heredity
Observed through patterns of inheritance, form the basis of modern genetics.
Any detectable and heritable change in the genetic material not caused by genetic recombination; mutations may occur within or between genes and are the ultimate source of all new genetic variation.
A process by which parents with different alleles give rise to progeny with genotypes that differ from either parent.
For example, parents with A B and a b genotypes can produce recombinant progeny with A b and a B genotypes.
The development and application of new mapping, sequencing, and computational procedures to analyze the entire genome of organisms.
Research method involving making observations, forming hypotheses to explain the observations, making experimental predictions based on the hypotheses, and, finally, testing the predictions.
The last step produces new observations, so a cycle is set up leading to a refinement of the hypotheses and perhaps eventually to the establishment of a law or an accepted principle.
Used frequently in transmission genetics, involves the breeding of two selected individuals and the subsequent analysis of their offspring to try to understand how traits are passed from parents to offspring.
(Sometimes called classical genetics) is the subdiscipline dealing with how genes and genetic traits are transmitted from generation to generation and how genes recombine (exchange between chromosomes).
Analyzing the pattern of trait transmission in a human pedigree or in crosses of experimental organisms is an example of this type of study.
Study of how genetic information is encoded within DNA and how biochemical processes of the cell translate the genetic information into the phenotype.
It is the subdiscipline dealing with the molecular structure and function of genes.
Analyzing the molecular events involved in the gene control of cell division, or the regulation of expression of all the genes in a genome, are examples of molecular genetics studies.
Genomic analysis is part of this type of genetics.
Study of the consequences of Mendelian
inheritance on the population level, including the mathematical description of a population's genetic composition and how it changes over time.
Study of the inheritance of complex characteristics that are determined by multiple genes.
recombinant DNA technology
Procedures that allow molecular biologists to splice a DNA fragment from one organism into DNA from another organism and to clone the new recombinant DNA molecule.
A collection of experimental procedures for inserting a DNA fragment from one organism into DNA from another organism and for cloning the new recombinant DNA.
polymerase chain reaction (PCR)
A method for producing many copies of a specific DNA sequence from a DNA mixture without having to clone the sequence in a host organism.
Experiments are done to gain an understanding of fundamental phenomena, whether or not the knowledge gained leads to any immediate applications.
Research done to further knowledge for knowledge's sake.
Research done with the objective of developing products or processes that can be commercialized or at least made available to humankind for practical benefit.
The production of many identical copies of a DNA molecule by replication in a suitable host; also called DNA cloning, gene cloning, and molecular cloning. (b) The generation of cells (or individuals) genetically identical to themselves and to their parent.
A type of analysis using PCR to amplify trace amounts of DNA in samples such as hair, blood, or semen samples collected from a crime scene.
The amplified DNA can be analyzed and compared with DNA from a victim and a suspect, and the results can be used to implicate or exonerate suspects in the crime.
Provides the means to search for specific information about a gene and its product.
An important resource for research that provides the means to search for specific information about a gene, including its sequence, its function, its position in the genome, research papers written about it, and details about its product.
Is a system for searching several linked databases. Including PubMed; Nucleotide, for the GenBank DNA and RNA sequences database; Protein, for amino acid sequences; Structure, for three-dimensional macromolecular structures; Genome, for complete genome assemblies; RefSeq, an annotated collection of genes, transcripts, and the proteins derived from the transcripts; OMIM, the Online Mendelian Inheritance in Man human gene database; and PopSet, population study datasets.
Is the National Institutes of Health (NIH) genetic-sequence database.
This database is an annotated collection of all the tens of billions of publicly available DNA sequences.
You search this database by entering terms in the search window.
For example, if you are interested in the human disease cystic fibrosis, enter the term cystic fibrosis into the search window, and you will find all sequences that have been entered into this database that include those two words in the annotations.
OMIM (Online Mendelian Inheritance in Man)
Is a database of human genes and genetic disorders authored and edited by Dr. Victor A. McKusick and his colleagues.
A search is performed by entering terms in a textbox search window; the result is a list of linked pages, each with a specific entry number.
The pages have detailed information about the gene or genetic disorder specified in the original search, including genetic, biochemical, and molecular data, along with an up-to-date list of references.
NCBI (National Center for Biotechnology Information)
Was created in 1988 as a national resource for molecular biology information.
Its role is to "create public databases, conduct research in computational biology, develop software tools for analyzing genome data, and disseminate biomedical information—all for the better understanding of molecular processes affecting human health and disease."
BLAST ((Basic Local Alignment Search Tool)
Is a tool used to compare a nucleotide sequence or protein sequence with all sequences in the database to find possible matches.
This is useful, for example, if you have sequenced a new gene and want to find out whether anything similar has been sequenced previously.
Moreover, genes with related functions may be listed in the databases, allowing you to focus your research on the function of the gene you are studying.
Is used to access literature citations and abstracts and provides links to sites with electronic versions of research journal articles.
These articles can sometimes be viewed, or you must pay a one-time fee or obtain a free subscription.
You perform a search by entering terms, author names, or journal titles.
It is highly recommended that you use this database to find research articles on genetic topics that interest you.
Database for the GenBank DNA and RNA sequences database.
Database for amino acid sequences.
A database for three-dimensional macromolecular
Database for complete genome assemblies.
An annotated collection of genes, transcripts, and the proteins derived from the transcripts.
Population study datasets.
Show the arrangments of genes alone the chromosomes and the genetic distances between the genes.
A representation of the relative distances separating genes on a chromosome based on the frequencies of recombination between nonallelic gene loci; also called
A unit of measurement for the distance between two genes on a genetic map. A recombination (crossover) frequency of 1% between two genes equals 1 mu. See also centimorgan.
The position of a gene on a genetic map; the specific place on a chromosome where a gene is located.
More broadly, a locus is any chromosomal location that exhibits variation detectable by genetic or molecular analysis.
Any organism whose cells have a membrane-bound nucleus in which the genetic material is located and
membrane-bound organelles (e.g., mitochondria).
Can be unicellular or multicellular and constitute one of the three major evolutionary domains of organisms.
Any organism whose genetic material is not located within a membrane-bound nucleus.
This group is divided into two evolutionarily distinct groups, the Bacteria and the Archaea.
Prokaryotes that constitute one of the three main
evolutionary domains of organisms.
Prokaryotes that constitute one of the three main
evolutionary domains of organisms.
Qualities indicating a good selection for genetic research include: having a short life span, a mating produces a large number of offspring, is easy to handle, and most importantly, genetic variation existing between the individuals in the population or be created
in the population by inducing mutations so that the
inheritance of traits can be studied.
A discrete structure within eukaryotic cells that is
bounded by a double membrane (the nuclear envelope)
and contains most of the DNA of the cell.
A lipid bilayer that surrounds the cytoplasm of both plant cells and animal cells.
In a eukaryotic cell, the double membrane that surrounds the nucleus and is perforated with pores that is selectively permeable allowing certain materials to flow between the cytoplasm and nucleus.
The outer membrane is continuous with the endoplasmic reticulum.
endoplasmic reticulum (ER)
A double-membrane structure that is part of the endomembrane system and is continuous with the nuclear envelope.
The rough ER has ribosomes attached to it, giving it a rough appearance, whereas the smooth ER does not.
Ribosomes bound to rough ER synthesize proteins to be secreted by the cell or to be localized in the plasma membrane or particular organelles within the cell.
The synthesis of proteins other than those distributed via the ER is performed by ribosomes that are free in the cytoplasm.
A large, complex cellular particle composed of ribosomal protein and rRNA molecules that is the site of amino acid polymerization during protein synthesis (translation).
Organelles found in the cytoplasm of all aerobic
animal and plant cells in which most of the cell's ATP is
Triple-membraned, chlorophyll-containing organelles found in green plants in which photosynthesis occurs.
The process that converts the nucleotide sequence
of an mRNA into the amino acid sequence of a polypeptide. Also called protein synthesis.
Class of RNA molecules that contain coded information specifying the amino acid sequences of proteins.
Also called basal bodies, are found in the cytoplasm of nearly all animal cells, but not in plant cells.
It is located in the center of the centrosome, a region of undifferentiated cytoplasm that organizes the spindle fibers that are involved in chromosome segregation in mitosis and meiosis.
A rod-shaped bacterium common in the intestines of humans and other animals.
transposons or transposable elements
-Are sequences of DNA that move (or jump) from one location in the genome to another.
-Are also ubiquitous (found everywhere) playing a role not only in the evolution of species but also in some human diseases.
Genetics: Core Concepts
-Mendel Discovers the rule of heredity (1865)
-The gene is the unit of inheritance of a trait.
-Darwin's "theory of evolution through natural selection" (1859)
-DNA is the genetic material (1940's -1950's)
-Crick (1958): the central dogma of molecular biology (DNA-RNA-Protein)
-Triplet Code (1960's)
-Many new disciplines emerged: Biotechnology, Molecular Biology, Bioinformatics, Genomics, Proteomics etc.
Pre-Mendelian Concepts of Heredity
-Many biologists held to the idea of blending inheritance during the 19th century, prior to the discovery of genetics.
-Blending inheritance refer to the blending of the genes and the phenotypes. If two alleles blend together, they would never be separated.
-Incomplete dominance results in blending only of the phenotype, keeping the alleles within the heterozygote distinct (and, thus still inheritable in successive generations).
-Particulate theory of Inheritance
-Gene (factor) is the unit of inheritance.
-Rule of genetic heredity
-Experimental species: pea plants
-Dominant and recessive traits: Passed down from one generation other with a specific ratio.
Alleles- Alternative versions of a gene (A and a)
Genotype- The complete genetic make up of the organism
Phenotype- All the observable properties of the organism.
Homozygous- An organism has a pair of identical alleles for the trait
Heterozygous- An organisms has two different alleles for the trait
Alternative versions of a gene (A and a)
The complete genetic make up of the organism
All the observable properties of the organism.
An organism has a pair of identical alleles for the trait
An organisms has two different alleles for the trait
Mendel's Law of Heredity
Law of Segregation: Factors separates randomly into the gametes. Diploid (2n) into haploid (n): Purple flower and white flower
Law of Dominance
Law of Independent Assortment: the two factors (Alleles: P/p: flower color) controlling one trait assorted independently from the two factors (Alleles: T/t: Height) controlling another trait.
Law of Segregation
Factors separates randomly into the gametes. Diploid (2n) into haploid (n): Purple flower and white flower
Law of Independent Assortment
the two factors (Alleles: P/p: flower color) controlling one trait assorted independently from the two factors (Alleles: T/t: Height) controlling another trait.
Organism for Genetic Research
A well known genetic history
A short life cycle, so that a large number of generations can be studied within a short time.
A large number of offspring
The organisms are easy to handle.
Enough genetic variation and phenotypes among individuals within a population
No moral and ethical concerns on mating design.
Hermann J. Muller
X-ray irradiated flies were crossed to produce offspring
Germ line mutation or somatic mutation
Thomas Hunt Morgan
Studied fruit flies.
Sex-linked inheritance: eye color gene is located on X-chromosome in fruit fly.
Genes are also carried on other chromosomes.
Genetic map: Using recombinants, map the locations of genes on chromosomes.
Nobel prize 1930
George Beadle and Edward Tatum
Genes Control steps in metabolic pathway (1030s)
Genes are responsible for the production of enzymes.
Discovery: "one gene-one enzyme" concept.
James Watson and Francis Crick
Solved 3D structure of DNA (1953)
DNA molecule is made of a double helix
DNA can reproduce itself without changing its structure, except for occasional mutations.
Nobel Prize in 1962
Variation in Genetic Material
-Genetic materials: DNA and RNA
-Prokaryotes (no nucleus): A single circular chromosome, and one or more plasmids
-Multiple and also linear chromosomes in complex bacterial genomes (new discovery)
-Eukaryotes (true nucleus): Multiple linear chromosomes (DNA)
-Viruses: Nucleic acids (DNA or RNA); Virion: RNA without any coat protein
NUCLEIC ACIDS: DNA & RNA
-DNA: Deoxyribonucleic acid (double strands)
-RNA: Ribonucleic acid (single strand)
-Building block- Nucleotide: Sugar-phosphate backbone and nitrogenous bases (A, T, C, G, and U)
-DNA-Deoxyribose, A, T, C, and G ; RNA-Ribose, A, U, C, and G
-Double Helix: Nitrogenous bases are bonded with hydrogen bonds: C...G, A..T
Transmission Genetics/Molecular Genetics
-Genetic and Non-genetic traits
Mendelian Genetics: Monogenic, Polygenic, and Pleiotropic traits
-Molecular Genetics: the central dogma of molecular biology:
-Transmission of genetic information: DNA replication
-Expression of genetic information: Transcription, Translation, and Gene Regulation
-One gene one polypeptide (prokaryotes); one gene-many polypeptide (eukaryotes)
Monogenic Traits in Human: Dominant phenotype
Free ear lobe
Clasping hands L/ R
Middle digit hair
Long Eyelash length
Almond eye shape
Monogenic Traits in Human: Recessive phenotype
Non rolling tongue
Attached ear lobe
Normal five fingers
Clasping hands R/L
No Chin cleft
No middle digit hair
Short Eyelash length
Round eye shape
No widow's peak
Legal and social concerns
Powerful new techniques raise ethical, legal, and social concerns that will need thoughtful solutions.
Stem cell research: Human cloning
In-vitro fertilization, Designing characteristic traits for the baby
Using biological weapons (small pox virus)
Synthetic cell (Craig Venter- 2010): synthesized bacterial species, which can reproduce computer generated genetic material in the cell.
DNA evolves from RNA
stable, less reactive, package more information
Genetic OrganizationGenes, Chromosomes, and Genome
-Gene: specific sequence of nucleotides which encodes protein/enzyme.
-Chromosome: DNA is complexed with histone proteins, called chromosomes. Species specific
-Genome: The complete DNA sequence of the haploid set in an organism.
-DNA Replication: DNA makes DNA
-DNA polymerase is the key enzyme.
-Both strands act like templates to synthesize two new strands.
-Semi-discontinuous DNA synthesis
-DNA synthesis occurs in S phase of the cell cycle.
-DNA to RNA
-Types: mRNA, rRNA, and tRNA.
-Only one strand acts like template
-RNA polymerase mRNA (codon) specified the amino acid sequence
-Small nuclear RNA (SnRNA), MicroRNA
-mRNA to polypeptide
-Site: ribosomes (in the cytoplasm)
-mRNA (64 codons) is decoded by tRNA anti-codon
-Ribosomal RNA: peptidyl transferase enzyme
Source of genetic variation: mutation, recombination, independent segregation of chromosomes, and random fertilization
Factors that affect the genetic variation: Population size, nonrandom mating, gene flow, and natural selection
Genetic divergence between populations leads to species formation
Basic and Applied Genetic Researches
Basic and applied researches have common technologies but their goals are different.
Bred animals: reducing the amount of fat in beef and pork
Crop plants: increasing the amount of protein
Developing diagnostic tests for genetic diseases and new pharmaceutical innovations
Recombinant DNA Technology
It is easier now to introduce traits of disease resistant from non-cultivated plants to crop plants.
DNA technology is being used to increase the amount of lean meat, the amount of milk, and the number of eggs.
Production of many antibiotics, hormones, blood clotting factors, and human insulin etc.
Use in forensic and anthropological studies
-National Center for Biotechnology Information (NCBI) http://www.ncbi.nlm.nih.gov
-PubMed- literature citation, abstract and provide links to the sites with electronic versions of journal articles
-Online Mendelian Inheritance in Man (OMIM) database of human genes and genetic disorders
-Blast compares DNA and protein sequences (BlastN, BlastP, BlastX)
-Gene Bank is an annotated DNA sequence database.
-Entrez is a system for searching linked databases.
-Genetic maps: sites of genes on the chromosome, genetic distances between them based on recombination frequencies
Mendel's Law of Heredity Notes
- recessive alleles have a mutation that is the reason for phenotype to be masked by dominant phenotype in background
-Law of Independent Assortment applies to genes on two different chromosomes. It wont apply to genes on the same chromosome
one gene controls one phenotype
controls more than one phenotype
one gene influences two or more seemingly unrelated phenotypic traits. Consequently, a mutation in a pleiotropic gene may have an effect on some or all traits simultaneously
one gene has impact on other traits as a result
are a group of related genes that control the body plan of an embryo along the cranio-caudal (head-tail) axis
YOU MIGHT ALSO LIKE...
STAAR Biology Reporting Category #2
biology final exam (text four)
Bio test 5
Genetics test review pages 44-68
OTHER SETS BY THIS CREATOR
Heme Normal Ranges
Advanced Hematology Exam #7
Advanced Hematology Exam #3