Genetics Exam 2 - from Exam Review Sheet

Made From Exam 2 Review Sheet

In a family history, what does the “F” in the F-GENES mnemonic stand for? A. Family history of the condition B. Frequency of symptoms C. Fetal development D. First diagnosis

A. Family history of the condition

Why may a Punnett square be useful when discussing genetic risk? A. It confirms the severity of a disorder B. It estimates possible inheritance outcomes for each pregnancy C. It identifies every new mutation D. It determines when symptoms will begin

B. It estimates possible inheritance outcomes for each pregnancy

Which information is most useful in a three-generation family history? A. Only the patient's current symptoms B. Health history from relatives across three generations C. Only the patient's siblings' diagnoses D. Only causes of death in grandparents

B. Health history from relatives across three generations

In a pedigree, who is the proband? A. The oldest family member B. The first person in the family known to have a condition C. The person who has the most children D. The family member with no symptoms

B. The first person in the family known to have a condition

In a typical pedigree, what does a square represent? A. A female B. A male C. A person with an unknown sex D. A deceased person

B. A male

A condition appears in every generation and affects males and females. An affected person often has an affected parent. Which inheritance pattern is most consistent with this? A. Autosomal dominant B. Autosomal recessive C. X-linked recessive D. Mitochondrial only

A. Autosomal dominant

Two unaffected parents have a child with an autosomal recessive disorder. What is the most likely explanation? A. Both parents carry a disease-associated allele B. The disorder must be X-linked dominant C. The child inherited two dominant disease alleles D. Neither parent can pass on the allele

A. Both parents carry a disease-associated allele

An X-linked recessive condition is often more common in males because males typically have: A. Two X chromosomes B. One X chromosome and one Y chromosome C. Two Y chromosomes D. No sex chromosomes

B. One X chromosome and one Y chromosome

Which statement best describes a major anomaly? A. A minor variation with no functional significance B. A structural abnormality with significant medical or functional consequences C. A temporary behavior change D. A normal variation in hair color

B. A structural abnormality with significant medical or functional consequences

Which statement best describes a minor anomaly? A. A feature that is always life-threatening B. A subtle physical feature that usually has limited medical significance by itself C. A disorder caused only by infection D. A defect that always requires surgery

B. A subtle physical feature that usually has limited medical significance by itself

A congenital defect caused by an intrinsic problem during organ development is called a: A. Malformation B. Deformation C. Disruption D. Dysplasia

A. Malformation

A normally developing body part is altered by mechanical forces, such as restricted space in the uterus. This is a: A. Malformation B. Deformation C. Disruption D. Syndrome

B. Deformation

A previously normal tissue or structure is damaged by an external destructive process. This is a: A. Dysplasia B. Deformation C. Disruption D. Sequence

C. Disruption

Abnormal organization of cells within a tissue is known as: A. Dysplasia B. Proband C. Metastasis D. Promotion

A. Dysplasia

A recognizable pattern of multiple anomalies that occur together and share a common cause is called a: A. Sequence B. Syndrome C. Pedigree D. Trait

B. Syndrome

A sequence is best described as: A. Several unrelated anomalies with no relationship B. A chain of anomalies where one primary defect leads to subsequent effects C. A chart of family relationships D. A change in DNA methylation only

B. A chain of anomalies where one primary defect leads to subsequent effects

Which is an important part of a dysmorphology assessment? A. Examining physical features and obtaining prenatal, birth, developmental, and family history B. Recording only the patient's height C. Avoiding family history D. Assessing only current medications

A. Examining physical features and obtaining prenatal, birth, developmental, and family history

An enzyme's main role is to: A. Store all genetic information B. Speed up biochemical reactions C. Form chromosomes only D. Prevent all mutations

B. Speed up biochemical reactions

Many inherited enzyme disorders are caused by variants that affect the enzyme's ability to: A. Catalyze a biochemical reaction B. Make bones longer C. Carry oxygen in every cell D. Produce all antibodies

A. Catalyze a biochemical reaction

Why can an enzyme disorder cause substances to accumulate in the body? A. A metabolic pathway may be blocked when an enzyme is deficient or dysfunctional B. Enzymes always destroy DNA C. All enzymes turn into hormones D. The kidneys stop functioning in every enzyme disorder

A. A metabolic pathway may be blocked when an enzyme is deficient or dysfunctional

Which is a possible management approach for some inherited metabolic enzyme disorders? A. Avoiding every source of protein in all cases B. Dietary modification and/or replacing a missing product when appropriate C. Stopping all routine monitoring D. Treating every disorder with antibiotics

B. Dietary modification and/or replacing a missing product when appropriate

Collagen is especially important for: A. Structural support and strength in connective tissues B. Carrying oxygen in red blood cells C. Transmitting electrical signals across synapses only D. Digesting carbohydrates in the stomach

A. Structural support and strength in connective tissues

A disorder affecting collagen may involve which finding? A. Increased connective-tissue fragility or joint hypermobility B. Only impaired color vision C. Complete immunity to fractures D. A guaranteed increase in muscle mass

A. Increased connective-tissue fragility or joint hypermobility

Why can some childhood genetic disorders persist in populations despite serious effects in individuals who inherit two disease-associated alleles? A. A carrier state may provide an advantage in a particular environment B. All genetic disorders improve survival C. Recessive alleles cannot be inherited D. Natural selection does not affect allele frequencies

A. A carrier state may provide an advantage in a particular environment

Sickle cell disease is most directly associated with: A. Abnormal hemoglobin that can cause red blood cells to sickle B. Lack of collagen in all connective tissues C. Excess insulin production D. Failure of DNA methylation in every cell

A. Abnormal hemoglobin that can cause red blood cells to sickle

Which statement best distinguishes sickle cell trait from sickle cell disease? A. Trait usually means one sickle hemoglobin allele; disease generally means two disease-associated hemoglobin alleles B. Trait always causes more severe symptoms than disease C. Trait cannot be inherited D. Disease occurs only after age 65

A. Trait usually means one sickle hemoglobin allele; disease generally means two disease-associated hemoglobin alleles

Which type of gene normally helps restrain cell division or promote DNA repair? A. Tumor suppressor gene B. Oncogene C. Ribosomal RNA gene only D. MicroRNA gene only

A. Tumor suppressor gene

An oncogene can contribute to cancer when it: A. Becomes abnormally activated and promotes cell growth or survival B. Always stops the cell cycle C. Repairs every DNA mutation D. Prevents cell division permanently

A. Becomes abnormally activated and promotes cell growth or survival

Why can an inherited cancer-risk variant increase risk without guaranteeing that a person will develop cancer? A. Other genetic and environmental factors can influence whether cancer develops B. Inherited variants are never expressed C. Cancer does not involve genes D. Every carrier develops cancer at birth

A. Other genetic and environmental factors can influence whether cancer develops

Which feature is more characteristic of a malignant tumor than a benign tumor? A. Invasion into nearby tissues and potential to metastasize B. A well-contained growth that never invades C. Normal regulation of cell division D. Inability to grow

A. Invasion into nearby tissues and potential to metastasize

What is metastasis? A. The spread of cancer cells to a distant site and formation of a secondary tumor B. A normal stage of embryonic development C. The repair of a DNA strand D. The conversion of RNA into DNA in every cell

A. The spread of cancer cells to a distant site and formation of a secondary tumor

In the multistep model of carcinogenesis, initiation generally involves: A. An initial genetic alteration in a cell B. The spread of a tumor to distant organs C. The removal of all abnormal cells D. The final shrinkage of a tumor

A. An initial genetic alteration in a cell

During carcinogenesis, promotion refers most closely to: A. Processes that encourage proliferation of initiated cells B. The first exposure to oxygen C. The spread of cancer to distant organs only D. The repair of every mutation

A. Processes that encourage proliferation of initiated cells

Which statement best describes progression in carcinogenesis? A. Tumor cells acquire additional changes associated with more aggressive behavior B. A normal cell completes mitosis C. A benign tumor can never change D. DNA sequence becomes irrelevant to cancer

A. Tumor cells acquire additional changes associated with more aggressive behavior

Which is an example of an environmental carcinogen or carcinogenic exposure? A. Tobacco smoke B. Normal hydration C. Regular handwashing D. Adequate sleep

A. Tobacco smoke

How can epigenetic changes contribute to cancer? A. They can alter gene expression, including genes involved in cell growth, without necessarily changing DNA sequence B. They always remove chromosomes C. They change every DNA base in a cell D. They prevent all transcription

A. They can alter gene expression, including genes involved in cell growth, without necessarily changing DNA sequence

BRCA1 and BRCA2 are important because they are involved in: A. DNA repair, and inherited harmful variants can increase certain cancer risks B. Hemoglobin production only C. Collagen formation only D. Digesting fats in the intestine

A. DNA repair, and inherited harmful variants can increase certain cancer risks

Epigenetics primarily refers to changes in: A. Gene activity or expression that do not require a change in DNA sequence B. The number of chromosomes in every cell C. The genetic code changing in every generation D. The amino-acid sequence of every protein

A. Gene activity or expression that do not require a change in DNA sequence

Which statement about epigenetic changes is most accurate? A. Some epigenetic marks can be influenced by environmental factors B. Epigenetic changes always alter the DNA base sequence C. Epigenetic changes cannot affect gene expression D. All epigenetic marks are permanent

A. Some epigenetic marks can be influenced by environmental factors

Which molecule receives a methyl group during DNA methylation? A. DNA B. Hemoglobin C. Collagen D. Glucose

A. DNA

In many gene-regulatory contexts, increased methylation near a gene's promoter is associated with: A. Reduced transcription B. Guaranteed increased transcription C. Immediate chromosome duplication D. Conversion of DNA into protein

A. Reduced transcription

The agouti mouse example is commonly used to demonstrate that: A. Maternal environment and diet can influence offspring coat color through epigenetic regulation B. Coat color is never influenced by gene expression C. DNA methylation always causes disease D. All mice have identical epigenetic patterns

A. Maternal environment and diet can influence offspring coat color through epigenetic regulation

What is a common effect of histone acetylation on chromatin? A. It often loosens chromatin and makes DNA more accessible for transcription B. It permanently deletes genes C. It converts RNA to protein directly D. It always silences every nearby gene

A. It often loosens chromatin and makes DNA more accessible for transcription

How can microRNA reduce protein synthesis? A. It binds target mRNA and can promote its degradation or inhibit translation B. It adds amino acids directly to DNA C. It creates a new chromosome D. It always increases translation of its target

A. It binds target mRNA and can promote its degradation or inhibit translation

Which statement about the microbiome is most accurate? A. Many microbes live in relationships with the human body that can support health B. All microorganisms are harmful pathogens C. The human body has no microbial communities D. The microbiome is made only of viruses

A. Many microbes live in relationships with the human body that can support health

Which is the best example of symbiosis between humans and microbes? A. Gut microbes help process certain food components while receiving a habitat and nutrients B. Every microbe causes disease C. Microbes never interact with the immune system D. Humans and microbes cannot coexist

A. Gut microbes help process certain food components while receiving a habitat and nutrients

A person has a disease-causing variant in a gene in a skin cell, but not in egg or sperm cells. What is the key inheritance implication? A. The somatic variant is generally not passed to children B. Every child will inherit the variant C. The variant must be inherited by all relatives D. The variant changes every cell in the person's body

A. The somatic variant is generally not passed to children

A family pedigree shows affected fathers do not pass a condition to sons, while daughters of affected fathers may be affected or carriers depending on the condition. Which inheritance clue is this most consistent with? A. An X-linked pattern B. An autosomal pattern that always affects only males C. A mitochondrial pattern passed by fathers D. A trait that cannot be inherited

A. An X-linked pattern

Which statement about a primary tumor is correct? A. It is the original site where a cancer began B. It is always a distant metastatic tumor C. It is always benign D. It contains no abnormal cells

A. It is the original site where a cancer began

Which statement best describes a carrier of a typical autosomal recessive disorder? A. The person has one disease-associated allele and often does not have the full disorder B. The person necessarily has two disease-associated alleles C. The person cannot pass the allele to offspring D. The person always has severe symptoms

A. The person has one disease-associated allele and often does not have the full disorder

A genetic counselor explains that each pregnancy is an independent event for a couple with a known autosomal recessive risk. What does this mean? A. The probability is recalculated for each pregnancy; previous outcomes do not determine the next one B. A first affected child guarantees the next child is affected C. A healthy child removes all future genetic risk D. The risk applies only to the first pregnancy

A. The probability is recalculated for each pregnancy; previous outcomes do not determine the next one