#7 MECHANISMS OF GENETICS

Match

Match the following

• Allele

• Dominant

• Genotype

• Homozygous

• Phenotype

letters represent characteristics (Pp)

trait that is expressed, capital letter

combo of alleles, usually 2 letters

having two identical alleles for a particular gene

appearance based on its genotype

• letters represent characteristics (Pp)

• trait that is expressed, capital letter

• combo of alleles, usually 2 letters

• having two identical alleles for a particular gene

• appearance based on its genotype

Labelling

Label your DNA

Drag labels to their correct position on the image

Phosphate

Sugar

Nitrogenous Base

In Summary...

DNA

RNA

Sugar is deoxyribose

Sugar is ribose

Double stranded helix

Single stranded helix

Uses Adenine (A), Guanine (G), Cytosine
(C)... but also uses Thymine (T)

Uses Adenine (A), Guanine (G), Cytosine
(C)... but also uses Uracil (U)

Made via DNA synthesis

Made via transcription

Only 1 main type in a somatic (body)
cell’s nucleus

Has 3 main types (mRNA, tRNA, rRNA) in
a cell.

Sends out messages, tells your body
what to do

Transcribes and translates messages on
DNA’s behalf

Categorize

Options (18)

Double Stranded

Helix Structure

Deoxyribose Sugar

Thymine Base

Adenine Base

Guanine Base

Cytosine Base

Replication Process

Single Stranded

Uracil Base

Ribose Sugar

Messenger RNA

Transfer RNA

Ribosomal RNA

Transcription Process

Translation Process

Organize these options into the right categories

DNA

RNA

Hotspot

List the step that is TRANSLATION.

Translation—process by which a protein is made from mRNA; tRNA matches

codons to amino acids which then join together to form a protein chain

Hotspot

List the step that is TRANSCRIPTION.

Transcription—process that copies DNA’s genetic information into messenger

RNA

Multiple Choice

What is the role of mRNA

• Carry an amino acid to the ribosome

• Copy the instructions from DNA and carry it out of the nucleus

• Make up the ribosomes

Multiple Choice

Where does Transcription occur

• Nucleus

• Ribosome

• ER

• Mitochondria

Multiple Choice

What is the mRNA for the following DNA strand?

TAC GTA

• GCT AGC

• ATG CAT

• AUG CAU

Multiple Choice

What amino acid is represented by the codon UUA?

• Phenylalanine

• Tyrosine

• Leucine

• Stop codon

Multiple Choice

Use your CODON CHART to answer the following question.

What amino acid is codded for by the codon GCA?

• serine

• alanine

• arginine

• proline

Match

Match the following CODONs with its corresponding Amino Acid

• GCA

• AAC

• AGC

• GAA

• CCC

Ala

Asn

Ser

Glu

Pro

• Ala

• Asn

• Ser

• Glu

• Pro

MUTATIONS

Changes in the DNA sequence

These mutations can cause a change in the mRNA sequence, and ultimately may change the protein synthesis. Mutations in DNA can be harmful, beneficial, or neutral, and can be passed to offspring only if it is in a

gamete.

Multiple Choice

DNA molecule segment is : TTACGCAAG
The mutated DNA segment is TTCGCAAG. This is an example of ___ mutation.

• Substitution
• Deletion
• Insertion
• Inversion

Multiple Choice

What mutation has occurred here? 
T-G-A-C-C-A
T-G-A-G-C-A

• Substitution
• Deletion
• Insertion
• Frameshift 

Multiple Choice

Original: ATC CAT
Mutation: ATC GCAT
What mutation occurred?

• deletion
• insertion
• silent
• transverse

​Punnett Square

​Punnett Square = a chart used to predict the genotype & phenotype of a trait in the offspring of two mates

​Punnett Square Rules

​Large letters are dominant and are written first

​

​Small letters are recessive and are written second.

​

​If both letters are present, the dominant trait will show in the phenotype.

​

​Try not to use letters which look the same in capital and lowercase.

​Punnett Square Terms

​Homozygous Dominant = two large letters for a trait

​

​Homozygous Recessive = two small letters for a trait

​

​Heterozygous (carrier) = one large letter and one small letter for a trait

How to use it

​

Punnett Square

Multiple Choice

What is the dominant trait?

• yellow pea seeds
• green pea seeds
• there is no dominant seed
• Jolly green giant

Multiple Choice

What are the possible genotypes for this cross?
(Click the picture to see it without the text)

• TT = 25% Tt= 50% tt=25%
• all tall
• TT= 75% tt = 25%
• Tt = 100%

Multiple Choice

What allele combination should go in the missing box?

• AA
• Aa
• aa
• none of these

What is a dihybrid cross?

*A dihybrid cross is a cross among two
traits.

DI= TWO
HYBRID=

COMBINATION

Dihybrid Punnett squares are
prediction tools used to determine
probability for two traits.

Problem: Show the possible genetic

combinations among offspring of a man who

is heterozygous for both dimples and

freckles, and a woman who is recessive for

dimples and freckles.

​FfDd x ffdd

Multiple Choice

In a dihybrid cross

• one trait is crossed.
• two traits are crossed.
• four boxes are needed for the punnett square.
• mom's alleles are dominant.

Multiple Choice

What goes in box 3

• Aabb
• AABB
• AAbb
• aaBb

Multiple Choice

What is the genotype for a pea plant homozygous for round seeds (R), and heterozygous for yellow seeds?

• RrYy

• RRyy

• RRYy

• rryy