DNA
What is the shape of DNA?
double-helix
What is a gene?
A gene is a section of DNA that codes for a specific trait.
What is a genetic mutation caused by?
A genetic mutation is caused by a change in a DNA sequence.
Create a Punnett Square for:
GG x Gg
G G
G GG GG
g Gg Gg
What is selective breeding?
The process by which scientists choose which organisms get to reproduce based on predictions of desirable traits in plants and animals.
Name the 4 nitrogenous bases of DNA.
Adenine, Thymine, Cytosine, Guanine
What is an allele?
An allele is a form of a gene.
Fill in the blank:
A genetic mutation can be harmful, beneficial, or ____________ to an organism's survival.
neutral
Create a Punnett Square for:
nn x Nn
n n
N Nn Nn
n nn nn
What is an example of a desired trait in plants?
Disease resistance, larger crops, greater quantity of crops, better taste, more vibrant colors, etc.
In the Strawberry DNA Lab, what was the purpose of adding the buffer (soapy, salty water) to the mashed up strawberries?
To chemically break down the cell membranes and cell walls of each strawberry cell
What is the difference between an organism's genotype and phenotype?
A genotype is the two-letter genetic code that includes both alleles for a trait.
A phenotype is the observable trait for which the genotype codes.
What type of mutation occurs when a base is replaced by another base in a DNA sequence?
Substitution
Brown eyes (B) are dominant to blue eyes (b). What is the probability of two heterozygous parents having a child with blue eyes?
Bb x Bb
There is a 25% chance that the child will have blue eyes.
What is an example of a desired trait in animals?
If A pairs with T and C pairs with G, what is the partner strand of the following DNA sequence:
ATG GCA TGT ACC CAG
TAC CGT ACA TGG GTC
What does heterozygous mean?
Having two different alleles
Original Sequence: ATT CGG TCT
New Sequence: ATT GGT CT
What type of mutation has taken place?
What base was mainly affected?
Deletion
ATT CGG TCT
Brown eyes (B) are dominant to blue eyes (b). What is the probability of a homozygous dominant parent and a homozygous recessive parent having a child with blue eyes?
BB x bb
There is a 0% chance that the child will have blue eyes.
Explain at least two harmful effects of selective breeding.
Genetic defects, inbreeding, greater risk of disease, etc.
What does DNA stand for?
deoxyribonucleic acid
What does homozygous mean?
Having two identical alleles
Original Sequence: ATT CGG TCT
New Sequence: ATC TCG GTC T
What type of mutation has taken place?
Insertion
ATC TCG GTC T
Brown eyes (B) are dominant to blue eyes (b). What is the probability of a heterozygous parent and a homozygous recessive parent having a child with blue eyes?
Bb x bb
There is a 50% chance that the child will have blue eyes.
What is the first step of selective breeding?
Choose parents with desired traits