Genetics Review KEY
Phosphate
DNA:
1. Color in the diagram below using this key:
Deoxyribose – red
Phosphate – blue
Adenine – yellow
Cytosine – green
Guanine – orange
Thymine - black
Deoxyribose
2. Circle one complete nucleotide in the drawing above.
3. What are the parts of one nucleotide?
Phosphate, deoxyribose (5-carbon), nitrogen base (A,T,G,C)
4. What is considered the backbone to the DNA strand?
Phosphate, Deoxyribose
5. Circle the complimentary strand.
6. What is DNA’s job?
Holds the genetic code – code for proteins and gene expression
7. Where does a mutation occur? (first DNA replication activity)
As an individual to multiple base(s) on the DNA strand. Switch out one base for a different base.
Mitosis:
1. Be able to identify a drawing of each phase, the major events that occur in each phase, and the correct
order in which the phases occur.
Interphase – prophase – metaphase – anaphase - telophase
2. What is characteristic of a cancerous cell? (Mitosis Internet Activity)
Replicates uncontrollably, with no stopping creating a mass called a tumor
Protein synthesis:
1. Fill in the blanks in the following chart.
DNA - Template Complimentary DNA
Strand
TTACGG
AATGCC
GGCGGC
CCGCCG
TGCATC
ACGTAG
AGACTC
TCTGAG
GATAAG
CTATTC
GACCGATGT
CTGGCTACA
mRNA
Amino Acids
AAUGCC
GGCGGC
ACGUAG
UCUGAG
GAUAAG
CUGGCUACA
asn, ala
gly – gly
Thr - stopi
Ser – glu
Asp – lys
Leu-ala-thr
Nucleus
2. Label the picture below using the following words:
codon, anticodon, ribosome, nucleus, tRNA,
mRNA, amino acid
tRNA
Amino
Acid
mRNA
Codon
Anti-codon
Ribosome
Codon
3. Distinguish between transcription and translation.
Transcription occurs in the nuclues, an enzyme reads DNA into RNA and replaces T with a U
Translation occurs in the cytoplasm, mRNA is read by the ribosome. It is read in triplets (codons) and
the matching tRNA brings the appropriate amino acid to make a protein.
4. What is the job of the mRNA, ribosome, tRNA, rRNA, amino acid.
mRNA – codes for protein
ribosome – reads the mRNA
tRNA – brings the amino acid to the ribosome
rRNA – ribosomal RNA
amino acid – monomer making up the polymer
5. How many amino acids are there? What codes for an amino acid?
20
Triplet codon on the mRNA
6. Fill in the table below:
DNA
5-carbon sugar
Deoxyribose
Ribose
Nucleotides
ATGC
AUGC
Single or double stranded
Double
Single
RNA
Inheritance:
1.
Define homozygous dominant
Same dominant alleles expressed on the chromosome (two capital letters)
2.
Define homozygous recessive
Same recessive alleles expressed on the chromosome (two lower case letters)
3.
Define heterozygous
One dominant and one recessive allele on the chromosome (One capital and one lower case
letter)
4.
Define allele
Different possible forms of the same gene
5.
6.
Outline the process of meiosis (how is it different from mitosis)?
Creates 4 haploid cells that are genetically different. It duplicates its DNA in interphase one, in
Metaphase 1 the chromosomes line up as pairs (instead of a single line) at the equator. The pairs
are separated in anaphase 1. Two haploid daughter cells are made. Each of those cells line their
remaining chromosomes on the equator and split them so the result is 4 daughter cells with half
of the genetic information.
Buttercup flower color is determined by a gene with 2 alleles. Yellow (Y) is the dominant allele, and
white (y) is the recessive allele.
a. Draw a Punnett square for the cross between a homozygous recessive white flowered plant
and a homozygous yellow flowered plant, providing the probability of each resulting
phenotype and genotype.
yy vs YY
y
y
Y
Yy
Yy
Y
Yy
Yy
100% Yy – heterozygous yellow
b. Cross two children from the parent cross (one just did). Provide the probability of each
resulting genotype and phenotype.
Yy vs Yy
Y
y
Y
YY
Yy
y
Yy
yy
25% YY – homozygous dominant – yellow
50% Yy – heterozygous – yellow
25% yy – homozygous recessive – white