BIO 100 EXAM 2

the particular genetic makeup of an individual

The visable measureable features of an individual

a single, large DNA molecule wrapped around proteins (histones); located in the nuclei of most eukaryotic cells

• one of the two identical DNA molecules that make up a duplicated chromosome following DNA replication
• connected at a region of the chromosome known as the centromere

• Same gene different alleles
• The two copies of each chromosome in a diploid cell. one chromosome in the pair is inherited from the mother, the other is inherited from the father

Genes located on the X and Y chromosome in males do not have a second copy

Alternative versions of the same gene that have different nucleotide sequences

• having two copies of every chromosome
• sex cells or gametes

• Having only one copy of every chromosome
• somatic cells (non-reproductive cells)

paired chromosomes present in both males and females; all chromosomes except the X and Y chromosomes

• Paired chromosomes that differ between male and female
• XX= Female
• XY= Male

Male

Having two different alleles of a given gene

Having two identical alleles of the same gene

An allele that can mask the presence of a recessive allele

an allele that reveals itself itself in the phenotype only if the organism has two copies of that allele

AA

• -mutation
• -chromosomes passed down

• Homologousmaternal and paternal chromosomes pair up and swap genetic information. Maternal chromosomes actually contain segments from paternal chromosomes and vice versa
• Meiosis I

• Alleles of different genes are distributed independently of one another, not as a package. A unique combination of maternal and paternal chromosomes is distributed into each sperm and each egg.
• Meiosis II

• two strands of linked nucleotides are bound together and twisted around each other to form a spiral-shapped double helix
• the sugars and phosphates = backbone
• bases = rungs

inside the nucleus in the form of chromosomes

DNA and protein (histones)

Ester Bonds

Hydrogen bonds

a sugar, a phosphate and a base

• the outside is phosphate groups and sugars alternating
• the middle is A,T,C,G held together by hydrogen bonds attached to a sugar

• 1. the helix unwinds and the two strands unzip
• 2. DNA polymerase pairs new nucleotides to each individual DNA strand matich A with T and C with G.
• 3. The end result is 2 molecules of DNA

DNA Polymerase

No, just different parts of the DNA are being read

• Polymerase Chain Reaction
• a laboratory technique used to replicate, and thus ampify, a specific DNA segment

• 1. Heating- separates DNA strands
• 2. Cooling- Allows DNA polymerase to pair new nucleotides with the original template strand

• -DNA
• -Nucleotides A,T,C,G
• -DNA polymerase
• -Primers

• 1. Collect cells and extract DNA from the crime scene evidence.
• 2. PCR amplify multiple STR regions
• 3. Separate STR's using gel electrophoresis

because it has a negative charge, and therefore it moves towards the positive end of the gel.

Sequences of DNA that serve as instructions for making proteins

DNA sequences that do not hold instructions to make protein

Non-coding sequences vary much more between individuals

STR (Short Tandem Repeat) Regions

23

46

A type of asexual reproduction in which one parental cell divides into two

a group of organisms of the same species living together in the same geographic area

Chance in allele frequencies in a population over time

The relative ability of an organism to survive and reproduce in a particular environment

Differential survival and reproduction of individuals in response to environmental pressure that leads to chance in allele frequencies in a population over time

The response of a population to environmental pressure, so that advantageous traits become more common in the population over time

Occurs when a single phenotype predominates in a paticular environment

occurs when phenotypes at each end of the spectrum are less suited to the environment than organisms in the middle of the phenotypic range

Tupically occurs in a "patchy" environment, in which extremes of the phenotypic range do better than middle range individuals