Learning from the Fossil Record
Grade 8 Science
Name: Colette Gilbert
Date: March 11, 2011
Mutations Justified True or False
Statement
1. Environmental factors
can lead to variations
between related
organisms.
2. Mutations can be caused
by environmental factors,
like chemicals and
sunlight.
True or False
True
True
3. Environmental factors
cannot alter genes.
False
4. Altered genes cannot be
passed on to offspring.
False
Justify why you chose T or F
If the environment changes,
the animals might have a
mutation is their genes
which causes them to
change. It could be a positive
or negative effect based on
their surroundings.
If chemicals get into the
body, the cells would have
something change their DNA
to something like making
less cells of one kind and it
could be a mutation that
changes the organism
permanently.
If something like cigarette
smoke gets into someone’s
body, that will hurt
something like their lungs to
affect them and not let them
work correctly to get oxygen
in and CO2 out of the body. If
the cells cannot function
correctly, a mutation will
occur to alter the genes
permanently to help or hurt
the organism it happened to.
If a mutated gene starts in a
mother, when she has
offspring, the new gene will
be passed to the children is it
was a dominant gene that
covers the normal gene that
was recessive. The gene can
get passed down whether it
was changed or not through
Learning from the Fossil Record
Grade 8 Science
Name: Colette Gilbert
Date: March 11, 2011
5. Mutations occur when
the genes in DNA are
changed and then passed
on.
6. Altered genes that are
passed on to offspring
can cause the traits of
generations to be
different.
7. Some mutations are not
passed on to offspring.
8. Mutations always create
a disadvantage for
offspring.
True
True
True
False
reproduction.
If the gene changes,
permanently, and then is
passed on to another person,
that person will have a gene
that is abnormal. Which
would cause something
different to happen to
someone’s body like
producing not enough or too
many of one kind of gene.
If one mother or father has a
mutated gene that gets
passed on to the offspring,
that gene would “take over”
and replace the normal gene
and that would keep getting
assed on through the
generation. It then becomes
the offspring’s gene
permanently and remains in
the generations because it is
the gene that is in each
system.
If the mutation occurs in the
recessive gene, and a
dominant gene is also passed
down, that would over
power the recessive mutated
gene. But if two recessive
genes are passed down, and
the mutation was in one,
than the mutation would
keep getting passed down.
Sometimes the mutation can
help animals bland in better
with their surroundings if the
environment is changing. If
its with humans, it could be
to be taller or shorter to help
Learning from the Fossil Record
Grade 8 Science
Name: Colette Gilbert
Date: March 11, 2011
9. The environment plays a
role in determining if a
mutation is an advantage
or a disadvantage.
10. All changes in traits are
due to mutations.
True
False
them be better at certain
things like sports. You don’t
know if the mutation is
positive or negative because
it all depends on their
environment. If the mutation
helps them blend in better,
they will live longer and
reproduce. It isn’t always
negative.
If an animal has dark fur in a
light environment, it is a
disadvantage because it gets
spotted more easily. If his
environment turns light, he is
at an advantage to his
surroundings because he
would blend in better and
survive longer. You don’t
know if the permanent
change in the organism is
good or bad until you know
how they normally survive in
their environment and how
they live now with the
mutation.
Sometimes a gene changes
because it has to adapt to
the environment because it
is changing, not because it
mutated.
Causes of Mutations:

Changes in DNA are
Learning from the Fossil Record
Grade 8 Science
Name: Colette Gilbert
Date: March 11, 2011
- Chemical
- Cigarette smokes
- Some drugs
- Pollution
- Radiation
- Excessive sunlight
1. Mutations  advantage or
disadvantage (both)
a. Traits  advantage or
disadvantage (both)
Learning from the Fossil Record
Grade 8 Science
Name: Colette Gilbert
Date: March 11, 2011
2. Environment causes mutation
3. Environment affects organisms’
survival
4. Environmental changes lead to
changes in organisms