Flashcards in Chapter 1: An Introduction to Genetics Deck (48):
How many genes are in the human genome?
What are the two processes via gene expression?
- transcription of DNA and translation of RNA
What is genetics?
the science of heredity and variation
What is heredity?
- transmission of traits from one generation to another
What is a trait?
- a detectable phenotypic variation of an inherited character
( blue vs brown eye colour)
What is a character?
- observable phenotypic attribute of an organism
Explain what a chromosome is / purpose.
- the organization of genes
- they vary in number and in size
- help to identify gene loci
- thread like structures in the nuclei carry hereditary
L> composed of protein and nucleic acids.
- one copy of genetic material subdivided into chromosomes
L> half the number of chromosomes (N)
L>haploid cells contain only one complete set of chromosomes
L> gametes and germ cells
L> products of meiosis
L> non homologous chromosomes
- two copies of genetic material subdivided into chromosomes
L> three pairs of homologous chromosomes
L> contain two complete sets of chromosomes (n)
L> products of mitosis
- somatic cells etc
Chromosomes are arranged in what kind of fashion in humans?
- linear arrangement of chromosomes from largest to smallest!
- where genes are located on the chromosome
map unit= genetic distance.....
By looking at mu of two genes ...if they are close to each other what can we establish?
- that they may be linked!
Allelic composition of one or more limited number of genes under investigation
L> specific genetic constitution of an organism
- observble expression of genetic make up...manifestation of genotype
L> genetically controlled observable features
- different versions of a gene
L> two alleles for one gene in a diploid individual
- identical alleles for a gene
- different alleles for a gene
( diff gene in each gamete )
Mendel's laws of inheritance go! (3)
1.Law of Segregation
2. Law of Independent Assortment
3. Law of Dominance
Mendel's laws of inheritance :
1. Law of Segregation? ( a lot)
1. two members of a gene pair (alleles) segregate (separate) from each other during the formation of gametes in meiosis. As a result half the gametes carry on allele the other half have the other allele. AKA Each gamete carries only a single allele of each gene...the progeny are produced by the random combination of gametes from the two parents.
When does segregation occur?
-members of a pair of alleles segregate during meiosis and that each offspring receives only one allele....therefore it parallels the separation of homologous pairs of chromosomes at anaphase 1 in meiosis.
Mendel's laws of inheritance:
2. Law of Independent Assortment?
the pairs of alleles for genes on different chromosomes segregate independently in the formation of gametes.
L> during meiosis 1
L>independent of each pair of homologous chromosomes...before separation in meiosis 1.
Mendel's laws of inheritance
3. Law of dominance?
the dominant form of a trait shows up in an individual that is heterozygous ( one dominant factor and one recessive factor )
Mendel's laws of inheritance
- Unit factors are said to be in ___.
L> one paternal and one maternal homologue
What three things account for genetic variation?
- change in the DNA or chromosome ( i.e. deletion, brewing of chromosome, inversion etc)
2. Recombination ?
- exchange of genetic material
- Favouring a combination of genes in a given environment ....product of selection = the next generation ( we the current generation don't matter sob)
- 1 copy go each chromosome (N)
- 2 copies of each chromosome (2N)
L> result from fusion of 2 games = zygote
- chromosomes that contain the same genes and pair during meiosis
- each member of a pair is a HOMOLOG
- chromosomes that do not contain similar genes
- do not pair during meiosis
exception to non homologous chromosomes not pairing in meiosis?
X and Y
What are the two types of Chromosomes ?
- autosomes ( do not determine sex)
- sex chromosomes ( xx and xy )
What is at the end of the chromosome that is responsible for aging via shortening of it?
L> repeating regions of dan ...non coding gene....
L> Y is telecentric (only one in us)
- distinguishable via the placement of the centromere
L> 2 arms are equal
L> 2 arms are unequal
L> stalk, satellite
L> centromere is just at the end of the chromosome .....( no division of arms)
Who created the first recombinant DNA molecule?
- Paul Berg
Who cloned the first recombinant DNA molecule?
- Boyer and Cohen
Who developed polymerase chain reaction?
- Kary Mullis
L> out of cell way to synthesize genes
Genomis = what?
- determination of complete genomic DNA sequences
Who created the artificial genome and inserted it into a prokaryotic cell?
- Craig Venter
- small DNA molecule that is separate from the chromosomal DNA and independently replicates
L> insert recombinant DNA into bacteria and it will integrate it ......
molecular structure and function of genes
study of heredity in groups of individuals for traits that are determined by one or only a few genes
study of heredity in groups of individuals but the traits are determined by many genes simultaneously