Download Test Review Sheet with Answers

Name________KEY_________________________________________
Period____________
Genetics Review Sheet
Parent Signature (3% extra credit on test)
I have studied this COMPLETED study guide with my student for at least 30 minutes ____________________
Inherited and Acquired Traits
1. What are traits? Traits are different forms of a characteristic. For example, the characteristic of eye color
could have traits of blue eyes, brown eyes, hazel eyes, green eyes.
2. What is the difference between an acquired trait and an inherited trait? Which is linked to genetics?
Acquired traits are ones you had to develop during your life time. Learning a skill or a sport is acquiring that
trait. Working out to get big muscles, piercing your ears or getting tattoos are all acquired traits. An inherited
trait is one you were born with. The trait is coded in your DNA which you got from your parents. If you have
freckles or a hitchhiker’s thumb, it is because it was in your DNA.
3. Identify the following as inherited or acquired:
Trait
Inherited/Acquired Trait
Flower petal length
Inherited
Dancing ability
Acquired
Freckles
Inherited
Knowledge about math
Acquired
Eye shape
Inherited
Tree health
Acquired
Genetics Terminology
1. Who is Gregor Mendel and what did he discover? Be specific! Gregor Mendel was an Austrian Monk who
studied pea plants. We call him the father of genetics because he figured out that offspring inherit separate
genetic information from each parent and that information stays separate, it does not mix.
2. Where is the DNA in a cell found? DNA is in the Nucleus. DNA combines to make genes which are
bundled together in chromosomes.
3. What does DNA stand for? (Make sure you have the correct spelling!) Deoxyribonucleic acid
4. DNA is made up of how many proteins and what are they called? 4. Cytosine, Guanine, Adenine, Thymine
5. What is the difference between a phenotype and a genotype? Phenotype is physical appearance and
Genotype is the genetic make up.
6. How many chromosomes do you have in each cell? How many from your Mom? Dad? Humans have 46
chromosomes. 23 pairs. Each parent gives 23 chromosomes to each child.
7. What is the difference between a dominant trait and a recessive trait? A dominant trait shows up whenever
the genes are present. A recessive trait could be covered up by a dominant trait, hiding the presence of the
recessive gene.
8. What type of letters represents a dominant trait? Upper Case/Capital A recessive trait? Lower case/Small
9. Define the following terms:
Homozygous: Having 2 of the same allele for a trait. Also called pure-bred for that trait
Heterozygous: Having 2 different alleles for a trait. Also called hybrid for that trait.
Offspring: The next generation of organisms created from existing organisms either by asexual or sexual
reproduction. Humans call offspring children.
Heredity: The passing on of traits from parents to offspring
Co-dominance: When alleles are neither dominant or recessive and both are expressed in an individual
Genotype: The genetic make up of an organism
Gene: A string of DNA code that contains the information for a given trait
Genetics: The study of Heredity
10. Answer the following questions based on this information:
Dominant
Recessive
Brown Eyes (B)
Blue Eyes (b)
Curly Hair (H)
Straight Hair (h)
a. If Susie has a Genotype of Bb HH, what would her Phenotype be?
Brown Eyes, Curly Hair
b. If Bob has a Phenotype of blue eyes and straight hair, what would his Genotype be?
bb, hh
c. Susie and Bob are getting married. If they had four kids, how many would have Blue eyes?
Use the punnett square to determine the answer.
b
B
Bb
b
Bb
2/4 would be Bb brown eyes
2/4 would be bb blue eyes
b
bb
bb
11. How is it possible to have a child with traits that neither of the parents have? The parents could each have
recessive traits and pass the genes for those to their child, allowing the child to express the recessive trait.
Asexual and Sexual Reproduction
Reproductive Strategies Venn Diagram
Fill in the Venn Diagram with information from the word bank which is true about asexual reproduction on the top, is true
about sexual reproduction on the bottom and is true about both asexual and sexual reproduction in the overlapping center.
two parents
Mix of traits
genetically
Plants use
this method
Ability to
adapt is high
Identical
genetically
Usually only a
few offspring
Lots of
offspring
Very slow
Very fast
One parent
clones
Bacteria use
this method
Lots of
diversity
Can use
either
method
Mammals use
this method
Offspring are
nurtured by
parent(s)
Ability to
adapt is low
Offspring are
on their own
from start
No diversity
Lots of
variety
Asexual
Reproduction
Identical Genetically Lots of offspring
Very fast
One Parent
Ability to adapt is slow
Clones
No diversity
Bacteria use this method
Offspring are on their own from start
Both
Plants use this method Can use either method
Two parents
Usually only a few offspring
Mix of traits genetically
Lots of Diversity
Ability to Adapt is High
Very Slow
Mammals use this method
Offspring are nurtured by parent(s)
Lots of Variety
Sexual Reproduction
1. What are the two main differences between asexual and sexual reproduction? (think of parents and offspring)
Asexual: One parent, no genetic variation = clones
Sexual: Two parents, genetic variation of offspring
2. Fill in the table
ADVANTAGES of ASEXUAL reproduction
Takes less energy
Happens very fast
Can have lots of offspring in a short time
3. Fill in the table
ADVANTAGES of SEXUAL reproduction
Variation of offspring means a species can adapt
to a changing environment.
DISADVANTAGES of ASEXUAL reproduction
No variation of offspring means the species cannot
adapt to a changing environment
DISADVANTAGES of SEXUAL reproduction
Takes a long time
Takes lots of energy
Produces fewer offspring at a time
4. Name 4 ways that organisms reproduce asexually?
Budding, Fission, Vegetative Growth, Fragmentation & Regeneration
5. Let’s say an organism lived in an environment that was always changing. Would it be better for that
organism to reproduce sexually or asexually? WHY? Sexually. At least some of the offspring would be suited
to the changing environment because they would all be different due to their genetic variation.
6. If an organism lived in an environment that changed very little, which way of reproduction would be better?
WHY? Asexually. All of the offspring would be ideally suited to the environment and would survive.
7. State whether the following situations is an example of asexual or sexual reproduction
a. A salmon laying eggs in a river that will be fertilized by another salmon
__Sexual________
b. Taking a clipping from a plant and growing a new plant from it
__Asexual_______
c. Two bacteria combining their DNA to produce a new, unique bacteria
__Sexual________
d. Taking the DNA of an organism and using it to produce a new organism
__Asexual_______
Man influencing Genetics
1. What is a GMO? Give the definition An organism which has had its genes modified in ways that do not
occur in nature.
2. Why do we have GMO’s? Scientists are adding genes to organisms to make them better able to survive and
benefit people.
3. How is selective breeding different from genetic modification? Selective breeding can only cross very
similar organisms. Genetic modification can cross completely different forms of life.
4. A tangelo is a cross between a tangerine and a grapefruit. Why do plant scientists make genetic cross like
this? Name at least three reasons. They make crosses to get fruit that is more beneficial for people, to make
plants more efficient at using energy to produce resources, and to make plants resistant to pests and disease.
Adaptations
1. What is a behavioral adaptation? An ACTION or BEHAVIOR that an organism does in order to help it to
survive in its environment.
2. What is a structural adaptation? A STRUCTURE or BODY PART that an organism has that helps it to
survive in its environment.
3. Why do dogs grow thicker fur in the winter and shed it in the summer? The thick fur gives warmth in cold
weather. Losing it in the summer helps dogs stay cooler in warm weather.
4. Why are the bones of a bird hollow? Birds with hollow bones are able to fly more efficiently. Hollow
bones are an adaptation that allows birds to fly.
5. Describe four examples of adaptations that animals might have to make them better able to survive in their
environment.
1. Snowshoe hare’s small ears prevent heat loss 2. Sharks light belly and dark back hide them
3. Polar bears black skin absorbs light/heat
4. Peppered moths match color of tree bark
6. Explain what a mutation is and what it has to do with adaptations. Mutations are copying errors that change
DNA code. Many adaptations are mutations that spread through a population because they provide a survival
advantage to the organisms which have the mutation.
7. What happened with the Peppered Moth story? Light moths were better at hiding from birds on light trees
till pollution made the trees darker. Then, the dark moths were better at hiding and they reproduced more.
After the pollution was cleaned up and the trees got lighter, the dark moths were worse at hiding and the light
moths were better at surviving and reproducing again.
8. Can a single organism adapt or does it occur over time in populations? Explain…A single organism
CANNOT adapt. Populations adapt over time as individual organisms either survive and pass on their genes or
die before they reproduce.