Download Genetics (20%) Sample Test Prep Questions

Genetics (20%)
Sample Test Prep Questions
Grade 7 (2a Genetics)
Students know the differences between the life cycles and reproduction methods of
sexual and asexual organisms. (pg. 106 Science Framework)
Summary: Sexual reproduction entails fertilization, an event in animals that requires the
fusion of an egg cell with a sperm cell. The fertilized egg (the zygote) goes through a
series of cell divisions (mitosis) and developmental steps to generate a new organism
genetically related to its parents. Pollination of flowering plants and growth of a new
genetically related plant from seed are more examples of a sexual life cycle.
Some organisms exclusively reproduce without a fertilization event. This method
is called asexual reproduction. Protists (single-celled eukaryotic organisms) often have
no known sexual cycle and reproduce solely by mitotic division. Fungi and plants often
have both sexual and asexual method of reproduction.
-------------------------------------------------------------Massachusetts Released Question
Single celled organisms can reproduce and create cells exactly like themselves
without combining genes from two different parent cells. When they do this, they
use a type of
A
B
C
D
asexual reproduction
gamete formation
natural selection
sexual reproduction
Answer: A. asexual reproduction
-------------------------------------------------------------Virginia Released Question
During mitosis, the doubling of chromosomes ensures that both new cells
A
B
C
D
.
have identical genetic makeup
are twice the size of the parent cell
serve different functions
remain attached to each other
Answer: A have identical genetic makeup
-------------------------------------------------------------
Oregon Released Question
Many plants reproduce asexually. How does the genetic material (DNA) compare
between the new plant and the parent plant in this type of reproduction?
A
B
C
D
It is similar but not identical
It depends on the plant the parent was crossed with
It depends on the climate it is grown in
It is identical
Answer: D It is identical
-------------------------------------------------------------Grade 7 (2c Genetics)
Students know an inherited trait can be determined by one or more genes. (pg. 107
Science Framework)
Summary: This standard draws a correlation between genes and the inherited trait or
features of an organism. A single gene can determine an inherited trait. For example,
attached or unattached earlobes is an inherited trait typically determined by a single gene
(inherited from each parent). A single gene may affect more than one trait or feature in
an organism. Many traits, such as hair and eye color, are determined by multiple genes
and do not have simple patterns of inheritance. Although an organism’s genes define
every inherited trait, there is not always a one-to-one correspondence between trait and
gene.
Illinois State Released Question
This is a diagram of a genetic cross. In guinea pigs, black hair color is dominant (B)
and white hair color is recessive (b). What hair color are the guinea pigs' offspring?
A
B
C
D
All Black
All White
Mostly black with some white
Mostly white with some black
Answer: C Mostly black with some white.
--------------------------------------------------------------
Grade 7 (2d Genetics)
Students know plant and animal cells contain many thousands of different genes and
typically have two copies of every gene. The two copies (or alleles) of the gene may or
may not be identical, and one may be dominant in determining the phenotype while the
other is recessive. (pg. 107 Science Framework)
Summary: This standard introduces some principles of Mendelian genetics. The most
significant concept is that genes exist in multiple versions, called alleles, and these units
of heredity are not typically changed during mating. Using true-breeding strains of peas
with a variation of a single gene (such as flower color), Mendel showed that the old
model of blending was incorrect.
Every person has tens of thousands of genes and that there are slight variations, or
alleles, of these genes in every individual. Every person has every gene (and usually in
two copies), but some people have an abnormal of different version (or versions) that can
lead to a disorder or different trait. The genetic traits of an individual are determined by
which alleles of genes are inherited from each parent and how those alleles work
together. Some alleles are dominant, meaning that they overcome the influence of the
other (recessive) alleles.
------------------------------------------------ ------------Florida Released Questions
In one species of guinea pig, the gene for black fur is dominant while the gene for
brown fur is recessive. A male guinea pig with black fur and a female guinea pig
with black fur produce an offspring with brown fur. Which most likely describes
the genes of the guinea pigs?
A Both parent guinea pigs carry the recessive gene.
B The male parent guinea pig carries the recessive gene, but the female parent does not.
C The female parent guinea pig carries the recessive gene, but the male parent does not.
D Neither parent guinea pig carries the recessive gene. The brown fur was a
spontaneous mutation.
Answer: A Both parent guinea pigs carry the recessive gene.
--------------------------------------------------------------
Virginia Released Question
Rabbit Test Cross Results
Parent Generation
F1
F2
Black X White
All Black
75% Black
25% White
What conclusion can be drawn from the genetic information above?
A. The white parent carried a dominant allele.
B. All the F1 rabbits carried a recessive allele.
C. All the white rabbits are heterozygous.
D. All the black rabbits in the F2 generation are homozygous.
Answer: B. All the F1 rabbits carried a recessive allele.
-------------------------------------------------------------Virginia Released Question
Mendel's early work with pea plants demonstrated a significant genetic discovery.
The crossing of homozygous tall pea plants with homozygous short pea plants
always resulted in tall plants and demonstrated that tallness in pea plants is a trait
that is
A blended
B dominant
C mutated
D recessive
Answer: B dominant
------------------------------------------------------------Tennessee Released Question
A cross between a red flowered plant (RR) and a white flowered plant (rr) is
shown in the Punnett Square below:
R
Rr
Rr
R
Rr
Rr
Which of the best describes the genotype of the offspring from this cross?
A
B
C
D
homozygous dominant
homozygous recessive
heterozygous dominant
heterozygous recessive
Answer: D heterozygous recessive
------------------------------------------------------------Grade 7 (2e Genetics)
Students know DNA (deoxyribonucleic acid) is the genetic material of living organisms
and is located in the chromosomes of each cell. (pg. 108 Science Framework)
Summary: Chromosomes in eukaryotes are complexes of DNA and protein.
Chromosomes organize the genetic make-up of a cell into discrete units. The proteins in
a chromosome help to support its structure and function, but the genetic information of a
cell is uniquely stored in the DNA component of the chromosome.
-------------------------------------------------------------New York Released Question
Hereditary information is found in a cell’s
A chloroplasts
B chromosomes
C cytoplasm
D membranes
Answer: B chromosomes
-------------------------------------------------------------Virginia Released Question
The Human Genome Project was begun in 1988 by scientists from 13 nations as a
worldwide effort to understand the sequencing of the entire DNA in the human
body. What is one potential scientific of this research?
A
B
C
D
It will help to explain human cultural differences
It will create communication between research centers
It will help find the genes responsible for many diseases
It helps to classify man most accurately in the animal kingdom
Answer: C It will help find the genes responsible for many diseases
--------------------------------------------------------------
Biology (2b Genetics)
Students know only certain cells in a multicellular organism undergo meiosis. (pg. 225
Science Framework)
Summary: Only special diploid cells, called spermatogonia in the testis of the male and
oogonia in the female ovary, undergo meiotic divisions to produce the haploid sperm and
haploid eggs.
-------------------------------------------------------------Virginia Released Question
The processes of meiosis and fertilization help ensure the survival of the species by
providing each generation with the same number of
.
A.
B.
C.
D.
body cells
cromosomes
offspring
gametes
Answer: B. chromosomes
-------------------------------------------------------------Virginia Released Question
The jimsonweed Daterra stramonium normally has 12 chromosomes in the body
cells. How many chromosomes will an egg cell of the jimsonweed have?
A
B
C
D
6 chromosomes
12 chromosomes
18 chromosomes
24 chromosomes
Answer: A 6 chromosomes
-------------------------------------------------------------Biology (2d Genetics)
Students know new combinations of alleles may be generated in a zygote through the
fusion of male and female gametes (fertilization). (pg. 226 Science Framework)
Summary: Once the gametes are formed, the second half of sexual reproduction can
take place. In this process a diploid organism is reconstituted from two haploid parts.
When a sperm is coupled with an egg, a fertilized egg (zygote) is produced that contains
the combined genotypes of the parents to produce that contains the combined genotypes
of the parents to produce a new allelic composition for the progeny. Students should be
able to read the genetic diploid karyotype, or chromosomal makeup, of a fertilized egg
and compare the allelic composition of progeny with the genotypes and phenotypes of the
parents.
Biology (2e Genetics)
Students know why approximately half of an individual’s DNA sequence comes from
each parent. (pg. 226 Science Framework)
Summary: Chromosomes are composed of a single, very long molecule of doublestranded DNA and proteins. Genes are defined as segments of DNA that code for
polypeptides (proteins). During fertilization half the DNA of the progeny comes from the
gamete of one parent, and the other half comes from the gamete of the other parent.
Biology (2f Genetics)
Students know the role of chromosomes in determining an individual’s sex. (pg. 226
Science Framework)
Summary: The normal human somatic cell contains 46 chromosomes, of which 44 are
pairs of homologous chromosomes and 2 are sex chromosomes. Females usually carry
two X chromosomes, and males possess one X and a smaller Y chromosome.
Combinations of these two sex chromosomes determine the sex of the progeny.
Biology (3a Genetics)
Students know how to predict the probable outcome of phenotypes in a genetic cross
from the genotypes of the parents and mode of inheritance (autosomal or X-linked,
dominant or recessive). (pg. 227 Science Framework)
Summary: Monohybrid crosses, including autosomal dominant alleles, autosomal
recessive alleles, incomplete dominant alleles, and X-linked alleles, can be used to
indicate the parental genotypes and phenotypes. The possible gametes derived from each
parent are based on genotypic ratios and can be used to predict possible progeny. The
predictive (probabilistic) methods for determining the outcome of genotypes and
phenotypes in a genetic cross can be introduced by using Punnett Squares and probability
mathematics.
California Released Question
If a corn plant has a genotype of Ttyy, what are the possible genetic combinations
that could be present in a single grain of pollen from this plant?
A
B
C
D
Ty, ty
TY,ty
TY,Ty,ty
Ty, ty, tY, TY
Answer: A Ty, ty
--------------------------------------------------------------
California Released Question
In fruit flies, the gene for red eyes (R) is dominant and the gene for sepia eyes (r) is
recessive. What are the possible combinations of genes in the offspring of two redeyed heterozygous flies (Rr)?
A
B
C
D
RR only
rr only
Rr and rr only
RR, Rr and rr only
Answer: D RR, Rr and rr only
-------------------------------------------------------------California Released Questions
In certain breeds of dogs, deafness is due to a recessive allele (d) of a particular
gene, and normal hearing is due to its dominant allele (D). What percentage of the
offspring of a normal heterozygous (Dd) dog and a deaf dog (dd) would be expected
to have normal hearing?
A
B
C
D
0%
25%
50%
100%
Answer: C 50%
--------------------------------------------------------------
California Released Questions
Fur color in cats is controlled by an autosomal gene that can occur in the dominant
form, (B), or the recessive form, (b). The length of the cat’s fur is controlled by
another autosomal gene which occurs in the dominant form, (S), or the recessive
form, (s). The table below shows the traits for these allele codes.
Gene
Trait
B
black fur
b
white fur
S
short-haired fur
s
long-haired fur
The following genotypes were found in a male cat and a female cat.
BbSs (male)
bbSS (female)
Which one of the following choices is true of the phenotype of offspring from these
parents?
A
B
C
D
All offspring will have black fur.
All offspring will have white fur.
All offspring will have long-haired fur.
All offspring will have short-haired fur.
Answer: D All offspring will have short-haired fur.
------------------------------------------------------------Illinois Released Question
This is a diagram of a genetic cross. In guinea pigs, black hair color is dominant (B)
and white hair color is recessive (b). What hair color are the guinea pig’s offspring?
B
BB
Bb
A
B
C
D
b
Bb
bb
All black
All white
Mostly black with some white
Mostly white with some black
Answer: C Mostly black with some white
--------------------------------------------------------------
New York Released Question
T
Tt
Tt
T
Tt
Tt
In a certain plant, the gene for tall height (T) is dominant over the gene for short
height (t). The Punnett square shows the results of a cross between a pure tall plant
and a pure shot plant.
Which process is represented by the use of the Punnett square?
A natural selection
B sexual reproduction
C pollination
D mutation
Answer: B sexual reproduction
-------------------------------------------------------------Virginia Released Question
A genetic pedigree showing that only males are affected by a certain disorder is
evidence of what type of inheritance?
A.
B.
C.
D.
dominant
sex-linked
recessive
passive
Answer: B. sex-linked
-------------------------------------------------------------Virginia Released Question
G
GG
Gg
g
Gg
Gg
In corn plants, green (G) is dominant to albino (g). According to the Punnett
square, what is the chance of this heterozygous cross producing an albino corn
plant?
A
B
C
D
one in four
two in four
three in four
four in four
Answer: A one in four
--------------------------------------------------------------
Biology (5a Genetics)
Students know the general structures and functions of DNA, RNA, and protein. (pg.
231-232 Science Framework)
Summary: Nucleic acids are polymers composed of monomers called nucleotides. Each
nucleotide consists of three subunits: a five-carbon pentose sugar, a phosphoric acid
group, and one of four nitrogen bases. DNA and RNA differ in a number of major ways.
A DNA nucleotide contains a deoxyribose sugar, but RNA contains ribose sugar. The
nitrogen bases in RNA are the same as those in DNA except that thymine is replaced by
uracil. RNA consists of only one strand of nucleotides instead of two as in DNA.
Proteins are polymers composed of amino acid monomers. Different types of
proteins function as enzymes and transport molecules, hormones, structural components
of the cells, and antibodies that fight infection.