Genomes and their Evolutions (Ch. 21)

Question 1

Bioinformatics

Answer 1

Combination of computer power and biology.

Question 2

Human Genome Project

Answer 2

Started 1990, ended in 2003. Helped establish databases & refine analytical software to make data available on the internet.

Question 3

Linkage Map

Answer 3

Shows location of several thousand genetic markers on a chromosome

Question 4

Physical map

Answer 4

Expresses distance between genes, usually as the number of base pairs.

Question 5

Metagenomics

Answer 5

Take DNA from soil and obtain DNA from group of species.

Question 6

Proteomics

Answer 6

The systematic studying of all protein and their functions.

Question 7

Noncoding DNA

Answer 7

Only 1.5% of our genome is transcribed into mRNA, tRNA or rRNA. Noncoding DNA (previously called junk DNA) is very important. Previously thought to be a sink against mutations.

Question 8

Intergenic DNA

Answer 8

In-between genes (not introns), noncoding.

Question 9

Pseudogenes

Answer 9

Former genes that have accumulated mutations and are nonfunctional. Intergenic DNA.

Question 10

Transposable elements

Answer 10

Barbara McClintock’s experiments. Observed effects of mobile DNA pieces, they moved from one site to another in a cell’s DNA. Present in both proks and euks.

Question 11

Transposable elements in euks

Answer 11

1. Transposons: Move via DNA intermediate
2. Retrotransposons: Move via RNA intermediate

Question 12

Alu elements

Answer 12

Transposable element-related DNA.
-Some Alu elements are transcribed, the function of the RNA molecules is unknown.
-Are a type of SINEs (Short Interspersed Nuclear Elements).

Question 13

SINE vs. LINE

Answer 13

a. SINE: Short interspersed nuclear element, non-coding repetitive DNA. 100-700 base pairs in length.
b. LINE/LTR: tend to be more abundant around genes of multi-copy gene families.

Question 14

LTRs

Answer 14

Long terminal repeat retrotransposons. Most abundant group of mobile genetic elements in eukaryotic genome. Essential in organizing genomic architecture and phenotypic variation.

Question 15

Simple Sequence DNA

Answer 15

Many copies of tandemly repeated units. i.e. STRs, short tandem repeats (Need at least 2 nucleotides), repeated thousands of times.

Question 16

Multigene Family

Answer 16

Collections of identical or very similar genes, some examples of identical (ex. rRNA genes) are clustered tandemly (opposite of interspersed (they have no space)).

Question 17

Duplications & inversions

Answer 17

Result from mistakes during meiotic recombination (crossing over, unequal c-o during prophase I).

Question 18

Highly Conserved genes.

Answer 18

Genes that can be studied in one model organism, and the results used for other phenotype. ??

Question 19

SNPs

Answer 19

Single Nucleotide Polymorphism. Substitution of a single nucleotide. Very common.

Question 20

CNVs

Answer 20

Copy Number Variance. Variation in copies of a particular gene or genetic region.

Question 21

Homeotic Genes

Answer 21

Specify identity of body segments in animal development.
-all contain a sequence known as the homeobox region (HOX), which codes for a homeodomain in the resultant protein.
-HOX sequences have been found in vertebrates & invertebrates, related sequences also in plants, fungi, & proks.