Download Second Nine Weeks Review

Name______________________________
Life Science Second Nine Weeks Review
Date______________________________
Period______________________________
The test on Wednesday, 1/22/14 will cover the following past units:
4.2 Cell Levels of Organization
6 Genetics
5.3 Cell Division
9 Changes Over Time
4.4 Cell Processes
Levels of Organization
The most basic level of organization is the _____________. In multicellular
organisms, the proper order for cellular organization (from least complex to most
complex) is:
___________________→___________________→_________________→_________________
Changes Over Time
Review the following terms:
Fossil _______________________________________________________________________
Adaptation ___________________________________________________________________
Mutation_____________________________________________________________________
Fossils are evidence that creatures lived on Earth millions of years ago. We call it
the _________ ___________ because it records a change in the structures so we can
compare modern organisms with those of the past.
The case of the English pepper moth is an example of how human actions can affect
natural selection. In the late 1700’s pepper moths were _____________ colored to
blend in with the bark of light gray trees and were able to avoid predation.
Natural selection favored the light colored moths over the black moths. However,
when the Industrial Revolution began soot accumulated and blackened the trunks
of the trees. As the result of a mutation, the ________________ colored moths were
better camouflaged and were able to avoid predators.
Is this mutation of black colored moths helpful, harmful or neutral? Explain your
answer in at least 1 complete sentence.
Cell Processes/Cell Division
Review the following definitions related to cell processes/cell division:
Diffusion ____________________________________________________________________
Osmosis _____________________________________________________________________
Active Transport _____________________________________________________________
Mitosis ______________________________________________________________________
Meiosis ______________________________________________________________________
Write in the proper cell process terms for the following sentences.
________________ The cell is mostly composed of water. The movement of water
particles from an area of high concentration to low concentration across a permeable
membrane. If too much water enters the cell, it will explode. On the other hand, if
too much water leaves the cell, it will wilt. This process does not require energy.
__________ ___________ Some molecules are much too large to move into the cell by
themselves. These molecules must be pumped, carried, or brought into the cell
using the energy molecule, ATP.
_______________ When a normal cell reaches a certain size, it needs to divide.
Before cell division occurs, the chromosomes must duplicate. At the end of the cell
cycle, the daughter cells contain an exact copy of the DNA of the parent cell. In
humans, this is 46 chromosomes.
_______________ The movement of molecules from an area of high concentration to
an area of low concentration across a semi-permeable membrane.
_______________ When the sex cells divide (eggs and sperm) they complete two
rounds of the cell cycle. At the end of this process, the chromosome numbers in the
eggs and sperm are half the number of the parent cell. In humans, this is 23
chromosomes.
In _________________reproduction, the offspring have identical DNA as the parents.
In ______________ reproduction, the offspring are different from the parents.
Genetics
Gregor Mendel’s work with pea plants marked the beginning of the study of
genetics, the scientific study of heredity. _________________ is the passing of traits
from parent to offspring. He knew nothing about genes in 1851. Mendel was
curious about why some pea plants had different characteristics, or traits. Some
were tall, others were short. Some had yellow pods, others had green pods, etc.
In Mendel’s first experiments, he used purebred plants. He know that the
combination of ________________ that control each trait exist in pairs. One could
show and mask another. Scientist today call the factors that control traits
___________. Different forms of the genes are called ___________________. Some
alleles are dominant and others are recessive.
Review the following terms:
Dominant ____________________________________________________________________
We indicate a dominant allele with a (capital/lower case) letter. Circle one.
Recessive ____________________________________________________________________
We indicate a recessive allele with a (capital/lower case) letter. Circle one.
When Mendel did his genetic studies, the term “gene” was not in use. Mendel used
the term ______________ instead.
Genes are carried from parents to their offspring on __________________________.
Only traits such as eye color can be __________________ because they are controlled
by genes. ________ carries genetic the code. The shape or structure of the DNA is a
___________ ________________, like a twisted ladder.
Any change in the gene or chromosome is called a ____________________. Mutations
may be helpful to an organism, harmful, or neutral.
Probability ___________________________________________________________________
Genotype ____________________________________________________________________
Phenotype ___________________________________________________________________
Homozygous _________________________________________________________________
Heterozygous ________________________________________________________________
Punnett squares show the possible outcomes of a genetic cross.
Complete the following Punnett squares:
Homozygous tall plants (TT) X homozygous short plants (tt)
What is the probability the offspring have the genotype TT_____, tt _____, Tt ______
What is the probability the offspring will have the phenotype tall _____, short _____
Heterozygous parents are mated (Bb)
What is the probability the offspring will be homozygous dominant? _______
What is the probability the offspring will be homozygous recessive? _______
What is the probability the offspring will be heterozygous? _______