PLTW Medical Interventions Unit 2 Exam Questions with Correct Answers Latest Update
2026/2027
Single-Gene Disorder - Answers Mutation in one gene, causes one protein to be made
incorrectly
Multifactorial Disorder - Answers Caused by a variety of mutations in several genes and introns
as well as environmental factors. They are often the cause of several chronic disorders.
Chromosomal Disorders - Answers Normal: 44 (22 pairs) autosomal chromosomes and 2 (1
pair) sex chromosomes.
Whole/partial missing/extra chromosome
Diagnosed with karyotypes (picture of the chromosomes)
Mitochondrial Disorders - Answers Caused by mutations in mitochondrial DNA (not in the
nucleus). Mitochondrial DNA is only passed down by the mother (only one copy of the gene).
Deals with energy and metabolism. It usually affects all cells in the body, but not always.
Carrier Screening - Answers Determines genotype of an individual when it cannot be determined
using a pedigree or the phenotype. It is often used by perspective parents to see if they are
carriers for a certain disease present in their families.
Preimplantation Genetic Diagnosis - Answers Used following in vitro fertilization. Babies are
tested for genetic defects and only healthy babies are inserted into the mother.
Amniocentesis - Answers Done during the second trimester of pregnancy. Takes a sample of
the amniotic fluid for genetic testing (requires use of an ultrasound)
Chorionic Villi Sampling - Answers Done during the first trimester of pregnancy. It cannot detect
neural tube defects. Takes a sample of chorionic villi on placenta wall for genetic testing
(requires use of an ultrasound)
Ultrasound - Answers Takes video of baby in womb, can determine fetus' age and sex, as well
as physical defects. It is also used to see the heartbeat and diagnose a pregnancy.
Newborn Screening - Answers Newborn babies are tested for a variety of genetic disorders and
defects. Tests vary from state to state.
Duchenne Muscular Distrophy - Answers Sex-linked recessive disorder, causes body to not
make protein dystrophin, causing muscle weakness.
Cystic Fibrosis - Answers Autosomal recessive, Causes problem in CFTR Protein, causing
mucus to clog lungs, persistent cough, and other lung problems.
, Huntington's Disease - Answers Autosomal dominant, doesn't show symptoms until later
in life. Makes defective protein known as Huntington. It is a degenerative brain disease
characterized by abnormal movements and a severe decline in thinking and reasoning skills.
Down Syndrome - Answers Caused by a problem after/during conception (missing whole/partial
chromosome 21). Characterized by small stature, physical defects, and mental retardation.
Leber hereditary optic neuropathy - Answers Mitochondrial disorder creates a defective
enzyme responsible for converting oxygen, fats, and simple sugars to energy.
Characterized by vision loss.
Alzheimer's Disease - Answers Early onset is autosomal dominant. Caused by a buildup
of beta-amyloid plaques and neurofibrillary tangles. Characterized by dementia and memory
loss.
Polymerase Chain Reaction (PCR) - Answers Denature: Highest temperature to separate strands
Anneal: Lowest temperature to allow primers to bind
Extend: Middle temperature to allow Taq polymerase to copy DNA
Final Extension: 10 minutes of extend to allow all DNA to copy.
Done in a thermocycler
Genotype - Answers Genetic code for a gene (TT, Tt, tt)
Phenotype - Answers Expression of gene (Taster, Non-taster, Weak taster)
How much of their genetic code do all humans share? - Answers 99.9%
Single Nucleotide Polymorphisms - Answers SNPs, Single nucleotide differences in the human
genome that separate each individuals. A difference of 1 base pair.
What steps should you take for a healthy pregnancy? - Answers 300 extra calories per day, no
under-cooked or unpasteurized foods, take prenatal vitamins, non-strenuous exercise, get plenty
of sleep, no hot tubs or saunas, no alcohol, no smoking, no drugs, no caffeine, limit exposure to
chemicals, take care of emotional health
12 week fetus - Answers sex determinable, heartbeat, arms proportional, more movement
24 week fetus - Answers senses present, nails develop
Why are older women more at risk for problems during their pregnancy, particularly genetic
problems? - Answers Older women's eggs are older, making fertilization more difficult and more
2026/2027
Single-Gene Disorder - Answers Mutation in one gene, causes one protein to be made
incorrectly
Multifactorial Disorder - Answers Caused by a variety of mutations in several genes and introns
as well as environmental factors. They are often the cause of several chronic disorders.
Chromosomal Disorders - Answers Normal: 44 (22 pairs) autosomal chromosomes and 2 (1
pair) sex chromosomes.
Whole/partial missing/extra chromosome
Diagnosed with karyotypes (picture of the chromosomes)
Mitochondrial Disorders - Answers Caused by mutations in mitochondrial DNA (not in the
nucleus). Mitochondrial DNA is only passed down by the mother (only one copy of the gene).
Deals with energy and metabolism. It usually affects all cells in the body, but not always.
Carrier Screening - Answers Determines genotype of an individual when it cannot be determined
using a pedigree or the phenotype. It is often used by perspective parents to see if they are
carriers for a certain disease present in their families.
Preimplantation Genetic Diagnosis - Answers Used following in vitro fertilization. Babies are
tested for genetic defects and only healthy babies are inserted into the mother.
Amniocentesis - Answers Done during the second trimester of pregnancy. Takes a sample of
the amniotic fluid for genetic testing (requires use of an ultrasound)
Chorionic Villi Sampling - Answers Done during the first trimester of pregnancy. It cannot detect
neural tube defects. Takes a sample of chorionic villi on placenta wall for genetic testing
(requires use of an ultrasound)
Ultrasound - Answers Takes video of baby in womb, can determine fetus' age and sex, as well
as physical defects. It is also used to see the heartbeat and diagnose a pregnancy.
Newborn Screening - Answers Newborn babies are tested for a variety of genetic disorders and
defects. Tests vary from state to state.
Duchenne Muscular Distrophy - Answers Sex-linked recessive disorder, causes body to not
make protein dystrophin, causing muscle weakness.
Cystic Fibrosis - Answers Autosomal recessive, Causes problem in CFTR Protein, causing
mucus to clog lungs, persistent cough, and other lung problems.
, Huntington's Disease - Answers Autosomal dominant, doesn't show symptoms until later
in life. Makes defective protein known as Huntington. It is a degenerative brain disease
characterized by abnormal movements and a severe decline in thinking and reasoning skills.
Down Syndrome - Answers Caused by a problem after/during conception (missing whole/partial
chromosome 21). Characterized by small stature, physical defects, and mental retardation.
Leber hereditary optic neuropathy - Answers Mitochondrial disorder creates a defective
enzyme responsible for converting oxygen, fats, and simple sugars to energy.
Characterized by vision loss.
Alzheimer's Disease - Answers Early onset is autosomal dominant. Caused by a buildup
of beta-amyloid plaques and neurofibrillary tangles. Characterized by dementia and memory
loss.
Polymerase Chain Reaction (PCR) - Answers Denature: Highest temperature to separate strands
Anneal: Lowest temperature to allow primers to bind
Extend: Middle temperature to allow Taq polymerase to copy DNA
Final Extension: 10 minutes of extend to allow all DNA to copy.
Done in a thermocycler
Genotype - Answers Genetic code for a gene (TT, Tt, tt)
Phenotype - Answers Expression of gene (Taster, Non-taster, Weak taster)
How much of their genetic code do all humans share? - Answers 99.9%
Single Nucleotide Polymorphisms - Answers SNPs, Single nucleotide differences in the human
genome that separate each individuals. A difference of 1 base pair.
What steps should you take for a healthy pregnancy? - Answers 300 extra calories per day, no
under-cooked or unpasteurized foods, take prenatal vitamins, non-strenuous exercise, get plenty
of sleep, no hot tubs or saunas, no alcohol, no smoking, no drugs, no caffeine, limit exposure to
chemicals, take care of emotional health
12 week fetus - Answers sex determinable, heartbeat, arms proportional, more movement
24 week fetus - Answers senses present, nails develop
Why are older women more at risk for problems during their pregnancy, particularly genetic
problems? - Answers Older women's eggs are older, making fertilization more difficult and more
