🩺 Chapter 25- genetics

The study of heredity is called:
a. Genomics
b. Genetics
c. Cytogenetics
d. Proteomics

Genetics

The total DNA content in a cell, including nuclear and mitochondrial DNA, is the:
a. Proteome
b. Genome
c. Chromosome
d. Karyotype

Genome

An alternative form of a gene found at the same locus on homologous chromosomes is a:
a. Genome
b. Codon
c. Allele
d. Chromatid

Allele

Which term refers to all proteins encoded by the genome?
a. Proteome
b. Genome
c. Transcriptome
d. Chromatin

Proteome

The p-arm of a chromosome is the:
a. Long arm
b. Short arm
c. Centromere
d. Noncoding region

Short arm

How many total chromosomes are found in a typical human somatic cell?
a. 22
b. 23
c. 44
d. 46

46

Autosomes are:
a. All chromosomes except the sex chromosomes
b. Chromosomes that determine sex
c. Mitochondrial chromosomes
d. Mutated chromosomes

All chromosomes except the sex chromosomes

The Y chromosome:
a. Is larger than the X chromosome
b. Contains genes unrelated to sex
c. Determines male sex characteristics
d. Contains no genes

Determines male sex characteristics

Which term describes a gene that masks the expression of another allele?
a. Dominant allele
b. Recessive allele
c. Codominant allele
d. Polygenic allele

Dominant allele

Which type of trait requires both alleles to be identical for expression?
a. Dominant
b. Recessive
c. Codominant
d. Polygenic

Recessive

What is the correct order in the central dogma of gene expression?
a. Protein → RNA → DNA
b. DNA → RNA → Protein
c. RNA → DNA → Protein
d. DNA → Protein → RNA

DNA → RNA → Protein

Which process produces gametes with half the number of chromosomes?
a. Mitosis
b. Meiosis
c. Fertilization
d. Replication

Meiosis

Which project revealed humans have approximately 20,000–25,000 genes?
a. ENCODE
b. Human Genome Project
c. 1000 Genomes Project
d. HapMap Project

Human Genome Project

Which is NOT a way genetic variation is increased in meiosis?
a. Crossing-over
b. Independent assortment
c. Random fertilization
d. Nondisjunction

Nondisjunction

The exchange of segments between homologous chromosomes is called:
a. Nondisjunction
b. Crossing-over
c. Gene linkage
d. Codominance

Crossing-over

When genes are located close together on a chromosome and tend to be inherited together, it is called:
a. Gene linkage
b. Crossing-over
c. Codominance
d. Independent assortment

Gene linkage

Which field studies how all proteins function and interact in an organism?
a. Cytogenetics
b. Proteomics
c. Genomics
d. Transcriptomics

Proteomics

The Human Genome Project found that less than:
a. 50% of DNA codes for proteins
b. 10% of DNA codes for proteins
c. 2% of DNA codes for proteins
d. 25% of DNA codes for proteins

2% of DNA codes for proteins

In albinism, which genotype produces the disorder?
a. AA
b. Aa
c. aa
d. AA or Aa

aa

A carrier for albinism has which genotype?
a. AA
b. Aa
c. aa
d. AA or aa

Aa

Which inheritance pattern occurs when both alleles are equally expressed?
a. Incomplete dominance
b. Codominance
c. Complete dominance
d. Polygenic inheritance

Codominance

Which type of inheritance results in traits more common in males?
a. Autosomal dominant
b. X-linked recessive
c. X-linked dominant
d. Mitochondrial

X-linked recessive

Which disorder is X-linked recessive?
a. PKU
b. Cystic fibrosis
c. Duchenne muscular dystrophy
d. Down syndrome

Duchenne muscular dystrophy

Which inheritance type passes exclusively from mother to all offspring?
a. X-linked recessive
b. Autosomal recessive
c. Mitochondrial
d. Polygenic

Mitochondrial

Which blood group system is an example of codominance?
a. ABO
b. Rh factor
c. MN system
d. O group

ABO

A Punnett square is used to:
a. Analyze chromosomes
b. Predict genetic probabilities
c. Diagnose chromosomal disorders
d. Sequence DNA

Predict genetic probabilities

Which is a cause of genetic mutation?
a. UV light
b. Chemicals
c. Viruses
d. All of the above

All of the above

Which type of mutation changes one base in the DNA sequence?
a. Frameshift mutation
b. Point mutation
c. Chromosomal mutation
d. Deletion

Point mutation

Which statement about mutations is correct?
a. All are harmful
b. All are beneficial
c. Some can be beneficial
d. None affect protein production

Some can be beneficial

A disease caused by a defect in one gene is called a:
a. Single-gene disorder
b. Chromosomal disorder
c. Polygenic disorder
d. Epigenetic disorder

Single-gene disorder

Which is a polygenic disorder?
a. Cystic fibrosis
b. Huntington disease
c. Hypertension
d. PKU

Hypertension

Which mechanism changes gene activity without changing DNA sequence?
a. Mutation
b. Epigenetics
c. Nondisjunction
d. Translation

Epigenetics

Which disorder is caused by overmethylation of the CGG repeat on the X chromosome?
a. Huntington disease
b. Fragile X syndrome
c. Tay-Sachs disease
d. PKU

Fragile X syndrome

Which condition results from trisomy 21?
a. Klinefelter syndrome
b. Turner syndrome
c. Down syndrome
d. Edwards syndrome

Down syndrome

Which karyotype pattern indicates Klinefelter syndrome?
a. XO
b. XXY
c. XY
d. Trisomy 18

XXY

Which condition is caused by monosomy X?
a. Turner syndrome
b. Down syndrome
c. Edwards syndrome
d. Fragile X syndrome

Turner syndrome

Which is NOT a result of nondisjunction?
a. Trisomy
b. Monosomy
c. Codominance
d. Extra chromosome

Codominance

Which chart shows family inheritance patterns?
a. Pedigree
b. Punnett square
c. Karyotype
d. Genome map

Pedigree

Which test uses amniotic fluid to obtain fetal cells?
a. NIPT
b. Amniocentesis
c. CVS
d. Ultrasound

Amniocentesis

Which test takes samples from placental tissue?
a. Amniocentesis
b. NIPT
c. Chorionic villus sampling
d. Fetoscopy

Chorionic villus sampling

Which test analyzes fetal DNA from the mother’s blood?
a. CVS
b. NIPT
c. Amniocentesis
d. Pedigree

NIPT

Which is a photographic map of chromosomes?
a. Genome map
b. Karyotype
c. Ideogram
d. Electrophoresis

Karyotype

Which technique separates DNA fragments by size?
a. PCR
b. Electrophoresis
c. Karyotyping
d. Replication

Electrophoresis

The main purpose of genetic counseling is to:
a. Treat genetic disorders
b. Manage genetic risks and decisions
c. Create genetic mutations
d. Replace defective genes

Manage genetic risks and decisions

Replacing a defective gene with a functional one is:
a. Gene augmentation
b. Gene replacement
c. RNA interference
d. Genome editing

Gene replacement

Adding extra copies of a gene to boost protein production is:
a. Gene replacement
b. Gene augmentation
c. RNA interference
d. HEC therapy

Gene augmentation

Silencing a harmful gene is:
a. RNA interference
b. Gene replacement
c. Gene augmentation
d. Gene suppression therapy

RNA interference

Delivering therapeutic genes to the lungs in cystic fibrosis can be done with:
a. Inhaler
b. Blood transfusion
c. IV drip
d. Surgery

Inhaler

The human engineered chromosome (HEC) method works by:
a. Deleting damaged genes
b. Adding an extra chromosome with therapeutic genes
c. Silencing unwanted genes
d. Replacing mitochondrial DNA

Adding an extra chromosome with therapeutic genes

Which disease was first successfully treated with gene therapy?
a. Cystic fibrosis
b. ADA deficiency
c. PKU
d. Hemophilia

ADA deficiency

In ADA gene therapy, which cells are targeted?
a. Red blood cells
b. White blood cells
c. Stem cells
d. Platelets

White blood cells

Who is considered the father of genetics?
a. Darwin
b. Mendel
c. Watson
d. Franklin

Mendel

Which scientists use genetics to improve crop yield?
a. Genetic engineers
b. Agricultural scientists
c. Genetic counselors
d. Proteomics specialists

Agricultural scientists

Genomics scientists focus on:
a. Mapping and analyzing genomes
b. Modifying proteins
c. Diagnosing genetic disorders
d. Studying environmental effects

Mapping and analyzing genomes

Which is an example of an autosomal recessive disorder?
a. Huntington disease
b. PKU
c. Hypercholesterolemia
d. Klinefelter syndrome

PKU

Which is an autosomal dominant disorder?
a. Tay-Sachs disease
b. Osteogenesis imperfecta
c. Cystic fibrosis
d. PKU

Osteogenesis imperfecta

Which single-gene disorder affects chloride ion transport?
a. Sickle cell anemia
b. Cystic fibrosis
c. PKU
d. Tay-Sachs

Cystic fibrosis

Which single-gene disorder results in abnormal hemoglobin?
a. PKU
b. Huntington disease
c. Sickle cell anemia
d. Tay-Sachs

Sickle cell anemia

Which disorder results from inability to break down phenylalanine?
a. PKU
b. Cystic fibrosis
c. Huntington disease
d. Tay-Sachs

PKU

Which disorder causes lipid buildup in brain cells, leading to death by age 4?
a. Huntington disease
b. PKU
c. Tay-Sachs
d. Down syndrome

Tay-Sachs

Which is a codominant single-gene disorder?
a. Sickle cell trait
b. Tay-Sachs
c. Cystic fibrosis
d. PKU

Sickle cell trait

Which genetic change affects chromosome structure but not gene sequence?
a. Epigenetic change
b. Mutation
c. Nondisjunction
d. Translation

Nondisjunction

Which group of disorders usually results from nondisjunction?
a. Single-gene disorders
b. Chromosomal disorders
c. Epigenetic disorders
d. Polygenic disorders

Chromosomal disorders

Which term describes an extra chromosome?
a. Monosomy
b. Trisomy
c. Polyploidy
d. Aneuploidy

Trisomy

Which term describes a missing chromosome?
a. Monosomy
b. Trisomy
c. Polyploidy
d. Aneuploidy

Monosomy

In genetic notation, “Aa” means:
a. Homozygous dominant
b. Heterozygous
c. Homozygous recessive
d. Codominant

Heterozygous

In a Punnett square, if both parents are Aa, the probability of an aa child is:
a. 0%
b. 25%
c. 50%
d. 75%

25\%

Which describes polygenic inheritance?
a. One gene controls one trait
b. Multiple genes influence a single trait
c. Genes act only with environment
d. Only dominant alleles are expressed

Multiple genes influence a single trait

Which field studies the impact of environment on gene activity without DNA change?
a. Genomics
b. Epigenetics
c. Proteomics
d. Cytogenetics

Epigenetics

Which genetic mechanism explains why siblings can look very different from each other?
a. Nondisjunction
b. Crossing-over & independent assortment
c. Mutation
d. Gene linkage

Crossing-over & independent assortment

Which genetic testing method poses the least physical risk to the fetus?
a. NIPT
b. Amniocentesis
c. CVS
d. Fetoscopy

NIPT

Which genetic counseling tool uses squares and circles to represent males and females?
a. Pedigree
b. Karyotype
c. Punnett square
d. Ideogram

Pedigree

Which field studies all RNA transcripts from the genome?
a. Transcriptomics
b. Proteomics
c. Genomics
d. Cytogenetics

Transcriptomics

Which single-gene disorder is autosomal dominant and causes progressive neurodegeneration?
a. Huntington disease
b. Tay-Sachs
c. PKU
d. Cystic fibrosis

Huntington disease

Which term describes an allele that can be hidden by another allele?
a. Dominant
b. Recessive
c. Codominant
d. Linked

Recessive