CHAPTER 3: The New Genetics Flashcards
No two cells of the human body contain exactly the same genetic instructions. TRUE or FALSE
TRUE
The genetic contribution of the father’s sperm determines whether a fertilized egg develops into a male or female. TRUE or FALSE
TRUE
Not all individuals are born genetically unique. TRUE or FALSE
FALSE
Humans have more than 100,000 genes. TRUE or FALSE
FALSE
All the genes a person has show up as observable characteristics. TRUE or FALSE
FALSE
The genomes of humans and chimpanzees are 99 percent identical. TRUE or FALSE
TRUE
There is a single alcoholism gene. TRUE or FALSE
FALSE
Middle-aged couples are less likely than younger couples to produce a child with a chromosomal abnormality. TRUE or FALSE
FALSE
Everyone carries several genes that could produce serious diseases or disabilities in their offspring. TRUE or FALSE
TRUE
Most known genetic disorders are transmitted through recessive genes. TRUE or FALSE
FALSE
Definition of genetic code?
molecular beginnings of human development
What is Deoxyribonucleic Acid (DNA)?
the chemical composition of the molecules that contain genes
What is chromosome?
one of 46 molecules of DNA (in 23 pairs) that virtually each cell of the human body contains and that, together, contain all the genes. Other species have more or fewer chromosomes
Definition of gene:
the basic unit for the transmission of heredity
Definition of zygote:
Two gametes (sperm and ovum) combine and produce a new individual with 23 chromosomes from each parent.
Definition of Gametes:
Reproductive cells
sperm and ova
Each gamete consists of how many chromosomes?
Each gamete consists of 23 chromosomes.
Even a small difference in one gene can cause major changes in a person’s….
A) genotype
B) phenotype
B) phenotype
Definition of genome:
Involves the full set of genes that are the instructions to make an individual member of a certain species
deifnion of Allele:
Variation of a gene or any of the possible forms in which a gene for a particular trait can occur
Single-nucleotide polymorphisms (SNP)
How many copies of each gene do humans get?
2 copies, on from each parent
Do the 2 copies of genes have to be identical with we get them?
no
Each variation of a gene is called an?
allele
How many chromosomes do humans usually possess?
46 chromosomes
Definition of phenotype:
The observable characteristics of a person.
Definition of genotype:
Organism’s entire genetic inheritance, or
genetic potential
Definition of homozygous:
Two genes of one pair that are exactly the
same in every letter of their code
Definition of heterozygous:
Two genes of one pair that differ in some way
How many chromosomes and genes do people have?
23 Pairs of chromosomes and about 20,000 genes.
What is an allele?
It is a variation that makes a gene different in some way from other genes for the same characteristic.
Why is each zygote unique, genetically?
When a sperm and an ovum combine, the zygote created is a new cell in which the genes on one of eight million possible sperm from the father interact with the genes on one of the eight million possible ova from the mother.
What determines whether a baby is a boy or a girl?
The sex depends on which sperm penetrates the ovum –a Y sperm, creating a boy (XY) or an X sperm, creating a girl (XX).
How are new cells (new people) formed?
The zygote begins duplication and division, and then differentiation and specialization occur.
Cells change from being stem cells, those from which any other specialized type of cell can form, to being only one kind of cell.
How many cells does a newborn have?
26 billion cells.
Each cell carries complete copy of genetic instructions
What are Stem Cells?
- Are first cells
- Are able to produce any other cell
- Can be reprogrammed
Definition of Assisted Reproductive Technology (ART):
General term for the techniques designed to help infertile couples conceive and sustain a pregnancy
What is In Vitro Fertilisation (IVF):
– Involves fertilization that takes place outside a woman’s body
– Involves mixing sperm with surgically removed ova from the woman’s ovary and implanting zygote into a woman’s uterus
There are two types of twins, what are they?
- monozygotic (identical) twins
- dizygotic (fraternal) twins
What are Monozygotic twins?
– Identical
– Originate from one zygote that splits apart very early in development
– Incomplete split results in conjoined twins.
– Same genotype but slight variations in phenotype are possible due to environmental influences.
What are Dizygotic twins?
– fraternal
– Result from fertilization of two separate ova by two separate sperm
– Dizygotic twins have half their genes in common and occur twice as often as monozygotic twins.
– Incidence is genetic and varies by ethnicity and age.
What is the Human Genome Project?
– Involves international effort to map the complete
human genetic code
– Was essentially completed in 2001, though analysis is ongoing
What are the interesting finding from the Human Genome Project?
– Humans have far fewer genes than previously
believed.
– All living creatures share many genes.
What are additive genes?
– Genes that add something to some aspect of the phenotype
• Effects of additive genes add up to make the phenotype.
What is Dominant-recessive heredity?
– Dominant gene is far more influential than the recessive gene (non-additive).
– Dominant gene can completely control the phenotype with no noticeable effect of recessive gene.
– Effect of recessive genes can sometimes be noticed.
Definition of carrier:
– Person whose genotype includes a
gene that is not expressed in the phenotype
• Unexpressed gene occurs in half of the carrier’s gametes and is passed on to half of the carrier’s offspring
Is this genotype or phenotype?
BB
genotype
Is this genotype or phenotype?
Brown eyed
phenotype
What is meant by X-linked?
– Special case of dominant–recessive pattern
– Gene carried on the X chromosome
– If recessive, the fact that it is on the X- chromosome is critical.
– Boys might have the phenotype, girls usually only carriers.
Genes on the X almost never have a match on the Y. Why?
The Y chromosome is much smaller than the X, containing far fewer genes.
The Y chromosome is much smaller than the X, containing far fewer genes. For that reason, genes on the X almost never have a match on the Y. Therefore, recessive traits carried on the X usually have ….
…no dominant gene on the Y
A boy, XY, with a recessive gene on his X has no corresponding dominant gene on his Y to counteract it, so his phenotype will be …
A) Affected
B) Not Affected
affected.
A girl will be affected only if she has the recessive trait on?
both of her X chromosomes.
Each human body cell contains _____ chromosomes.
A) 46 pairs
B) 23
C) 46
D) 23 pairs
C) 46
The name of the full set of genes that provides the instructions for making living organisms is the _____.
A) phenotype
B) genotype
C) genome
D) allele
C) genome
All living things are composed of cells. The work of cells is done by _____.
A) proteins
B) zygotes
C) genotypes
D) phenotypes
A) proteins
Every human begins life as a single cell, which is called a _____.
A) chromosome
B) genotype
C) zygote
D) genome
C) zygote
Individual A’s 23rd pair of chromosomes is XX. Individual A is _____.
A) male
B) neither male nor female
C) female
D) both male and female
C) female
The first 22 chromosome contain hundreds of genes in the same positions and sequence. If the code of the gene from one parent differs from the code on the same gene from the other parent, the gene pair is _____.
A) homozygous
B) monozygotic
C) heterozygous
D) dizygotic
C) heterozygous
Allen learned in his college biology class that, with respect to the sex chromosomes, the _____.
A) Y chromosome is larger than the X chromosome and has more genes
B) X chromosome is larger than the Y chromosome and has more genes
C) X and Y chromosomes are the same size, but the X chromosome has more genes
D) X and Y chromosomes are the same size and have the same number of genes
B) X chromosome is larger than the Y chromosome and has more genes
_____ cells are able to produce any other cells.
A) polymorphic
B) stem
C) foundation
D) allele
B) stem
Identical twins are also called _____ twins.
A) dizygotic
B) zygotic
C) gamete
D) monozygotic
D) monozygotic
The general term for the techniques designed to help infertile couples conceive and then sustain a pregnancy is _____.
A) in vitro fertilization (IVF)
B) artificial reproductive technology (ART)
C) intra-cytoplasmic injection (ICSI)
D) multifactorial
B) artificial reproductive technology (ART)
Which of the following women is most likely to have dizygotic twins?
A) Pallavi, who is Korean
B) Oluchi, who is Nigerian
C) Ember, who is American
D) Wei, who is Chinese
B) Oluchi, who is Nigerian
The _____ is the person’s appearance, behavior, and brain and body functions.
A) phenotype
B) genotype
C) allele
D) gamete
A) phenotype
The _____ was a worldwide effort to map the complete human genetic code.
A) hap map
B) Apgar scale
C) human genome project
D) brazelton assessment
C) human genome project
When the effects of genes combine to create the phenotype, they are called “_____ genes.”
A) dominant
B) additive
C) recessive
D) nonaddictive
B) additive
Lacy has a recessive gene in her genotype that is not expressed in her phenotype. She is a(n) _____ of that gene.
A) recipient
B) carrier
C) expressor
D) reactor
B) carrier
Michael is color-blind. His gene for color blindness is most likely a _____.
A) dominant gene on his X chromosome
B) dominant gene on his Y chromosome
C) recessive gene on his X chromosome
D) recessive gene on his Y chromosome
C) recessive gene on his X chromosome
Due to biological sex (XX or XY), women become drunk on _____ than men.
A) more alcohol
B) less acholol
C) the same amount of alcohol
D) more alcohol
B) less acholol
The most common extra-chromosome condition is _____.
A) Down syndrome
B) nearsightedness
C) fragile X syndrome
D) Tourette syndrome
A) Down syndrome
Most recessive genetic disorders are _____.
A) on the autosomes
B) X-linked
C) additive
D) polygenic
A) on the autosomes
The first 22 chromosomes contain hundreds of genes in the same positions and sequence. If the code of the gene from one parent is exactly like the code on the same gene from the other parent, the gene pair is _____.
A) homozygous
B) monozygotic
C) heterozygous
D) dizygotic
A) homozygous
A ____ women is more likely to experience a successful in vitro fertilisation (IVF) pregnancy:
A) older
B) younger
C) newly mother
D) mid 40s
B) younger
Oliver has inherited genes that put him at risk for developing diabetes, but he never develops diabetes due to a healthy diet and exercise. This example demonstrates that human characteristics, including diabetes, are _____
A) inherited
B) genetic
C) epigenetic
D) transferable
C) epigenetic
Michelle and Greg are having a baby and are hoping for a boy. _____ is who is responsible for determining the sex of the baby.
A) genetics
B) greg
C) Gregs mom
D) Michelle
B) greg
The cognitive deficits caused by the genetic condition of _____ are the most common form of inherited mental retardation.
A) fragile X syndrome
B) genetics
C) color boldness
D) autism
A) fragile X syndrome
On the 23rd pair of chromosomes, females have _____.
A) females don’t have a 23rd pair
B) XY chromosomes
C) two Y chromosomes
D) two X chromosomes
D) two X chromosomes
Which female is more likely to naturally conceive dizygotic twins?
A) a 23-year-old women
B) a 35-year-old women
C) a 19-year-old-women
D) a 60-year-old-womem
B) a 35-year-old women
_____ are more likely to be carriers of X-linked traits, and _____ are more likely to express them.
A) Males; males
B) Females; males
C) Females; females
D) any gender.
B) Females; males
The heritability for human traits, such as nearsightedness, _____.
A) is not dependent on genetics
B) is dependent on genetics
C) can differ between cultures
D) does not differ between cultures
C) can differ between cultures
As urbanization, video games, homework, and fear of strangers has kept more American children indoors, the rate of _____ has increased.
A) nearsightedness (myopia)
B) blindness
C) farsightedness
D) anger issues
A) nearsightedness (myopia)
Harold and Heather are twins. They are the result of _____.
A) one ovum fertilized by one sperm that split into two zygotes
B) two separate ova that were fertilized by two different sperms
C) two separate ova that were fertilized by two different sperms
two separate ova that were fertilized by two different sperms
Justin and Jacob are identical twins. They are the result of _____.
A) one ovum fertilized by one sperm that split into two zygotes
B) two separate ova that were fertilized by two different sperms
C) two separate ova that were fertilized by two different sperms
one ovum fertilized by one sperm that split into two zygotes
Which of the following is an example of a single-gene disorder that is dominant?
A.Huntington disease
B.fragile X syndrome(wrg)
C.Down syndrome
D.nearsightedness
A.Huntington disease
Jeff and Ashley are fraternal twins. They are the result of _____.
A) one ovum fertilized by one sperm that split into two zygotes
B) two separate ova that were fertilized by two different sperms
C) two separate ova that were fertilized by two different sperms
C) two separate ova that were fertilized by two different sperms
An individual’s phenotype is dependent on _____.
A) friends
B) genes
C) environment
D) genes and environment
D) an individual’s genes and the environment
Chromosomes are molecules of:
a) Genotype
b) Deoxyribonucleic acid (DNA)
c) Gamete
d) Pheotype
b) Deoxyribonucleic acid (DNA)
When a sperm and an ovum fuse, a one-celled __________ is formed.
a) Zygote
b) Reproductive cell
c) Gamete
d) Monozygote
a) Zygote
An individual’s genetic inheritance is called a(n) _________.
a) Phenotype
b) Allele
c) Genotype
d) Gamete
c) Genotype
Genes that produce characteristic traits through the interaction of genetics and environmental influences are referred to as:
a) Additive
b) Multifactorial
c) Polygenetic
d) Pheotypic
b) Multifactorial
Some men are color blind because they inherit a particular recessive gene from their mother. That recessive gene is carried on the:
a) X chromosome
b) XX chromosome pair
c) Y chromosome
d) X or Y chromosome
a) X chromosome
King Henry VIII of England had his wife beheaded because she failed to produce any male heirs to the throne. Which of the following is true?
a) King Henry was too old to have male offspring
b) King Henry just wanted a younger wife
c) It was King Henry’s “fault” that he had no sons, because only a male can contribute the Y chromosome containing the male development genes
d) Only females can contribute the Y chromosome containing the male development gene
c) It was King Henry’s “fault” that he had no sons, because only a male can contribute the Y chromosome containing the male development genes
Which of the following is a good reason for a couple to receive genetic counseling before then plan a pregnancy?
a) They have a history of high fertility
b) They have a diverse ethnic backgrounds
c) The women is under 30
d) They have relatives with serious genetic disorders.
d) They have relatives with serious genetic disorders.
The proper order for human growth before birth is:
a) Embryonic period, germinal period, zygotic period
b) Embryonic period, germinal period, fetal period
c) Germinal period, embryonic period, fetal period
d) Fetal period, germinal period, embryonic period
c) Germinal period, embryonic period, fetal period
The age of viability refers to:
a) The age when the fetus can survive outside the womb with medical help
b) The movement when fusion occurs and the zygote is formed
c) The age when the embryo becomes a fetus
d) The age of a full-term infant
a) The age when the fetus can survive outside the womb with medical help
The most critical period of vulnerability to teratogens occurs during:
a) The germinal period
b) The embryonic period
c) The fetal period
d) The entire pregnancy
b) The embryonic period
The most prevalent cause for small gestational age (SGA) babies is:
a) Marijuana
b) Tobacco
c) Heroin
d) Alcohol
b) Tobacco
The APGAR scale measures which of the following?
a) Heart rate
b) Eye color
c) Irritability
d) Capillary refill
a) Heart rate
You know that your friend is 3 months pregnant, and you notice that she is drinking wine. What is the potential outcome of her continued drinking during her pregnancy?
a) May cause premature labor
b) Normal use poses no threat
c) Fetal alcohol effects (FAE)
d) Can harm teeth
c) Fetal alcohol effects (FAE)
Because the entire embryonic stage is a critical period:
a) Pregnant women should do their best to “live clean” and avoid teratogens during this stage
b) Pregnant women should wait until this period is completed before seeing a physician
c) This stage should be eliminated from prenatal development
d) Pregnant women should seek advice from their friends
a) Pregnant women should do their best to “live clean” and avoid teratogens during this stage
