BIO280 EXAM 4 HIGH-YIELD Q&A STUDY GUIDE
(GENETICS & ENDOCRINE ESSENTIALS)
GENETICS & INHERITANCE
Q1: What is an allele?
A: An allele is a different version of the same gene.
Elaboration: Each gene can come in multiple forms, and the specific combination
you inherit affects how the trait is expressed.
Q2: What is a genotype?
A: A genotype is the genetic code composed of the alleles you carry.
Elaboration: It determines your potential traits, even if they are not outwardly
visible.
Q3: What does homozygous mean?
A: It describes having two identical alleles for a gene (AA or aa).
Elaboration: Homozygous individuals consistently pass on that allele to their
offspring.
Q4: What does heterozygous mean?
A: It means having two different alleles for a gene (Aa).
Elaboration: These individuals can pass either allele to their children.
Q5: What are dominant genes?
A: Dominant traits appear when at least one dominant allele is present (AA or Aa).
, Elaboration: Only one dominant allele is needed for the trait to show.
Q6: What are recessive genes?
A: Recessive traits appear only when both alleles are recessive (aa).
Elaboration: A single dominant allele will mask the recessive one.
Q7: What is autosomal dominant inheritance?
A: Disorders appear when one dominant allele is inherited.
Elaboration: Affected individuals are AA or Aa; carriers do not exist.
Q8: What is autosomal recessive inheritance?
A: Disorders occur only if both recessive alleles are present (aa).
Elaboration: Aa individuals are unaffected carriers who can still pass the gene on.
Q9: What does X-linked inheritance mean?
A: The trait or disorder is on the X chromosome.
Elaboration:
Females: need two recessive alleles to express it (xx) and can be carriers (Xx).
Males: one affected X means they have the condition—no carriers.
Q10: What is a karyotype?
A: A pictorial display of all chromosomes arranged in pairs.
Elaboration: It helps identify genetic abnormalities, such as trisomies.
(GENETICS & ENDOCRINE ESSENTIALS)
GENETICS & INHERITANCE
Q1: What is an allele?
A: An allele is a different version of the same gene.
Elaboration: Each gene can come in multiple forms, and the specific combination
you inherit affects how the trait is expressed.
Q2: What is a genotype?
A: A genotype is the genetic code composed of the alleles you carry.
Elaboration: It determines your potential traits, even if they are not outwardly
visible.
Q3: What does homozygous mean?
A: It describes having two identical alleles for a gene (AA or aa).
Elaboration: Homozygous individuals consistently pass on that allele to their
offspring.
Q4: What does heterozygous mean?
A: It means having two different alleles for a gene (Aa).
Elaboration: These individuals can pass either allele to their children.
Q5: What are dominant genes?
A: Dominant traits appear when at least one dominant allele is present (AA or Aa).
, Elaboration: Only one dominant allele is needed for the trait to show.
Q6: What are recessive genes?
A: Recessive traits appear only when both alleles are recessive (aa).
Elaboration: A single dominant allele will mask the recessive one.
Q7: What is autosomal dominant inheritance?
A: Disorders appear when one dominant allele is inherited.
Elaboration: Affected individuals are AA or Aa; carriers do not exist.
Q8: What is autosomal recessive inheritance?
A: Disorders occur only if both recessive alleles are present (aa).
Elaboration: Aa individuals are unaffected carriers who can still pass the gene on.
Q9: What does X-linked inheritance mean?
A: The trait or disorder is on the X chromosome.
Elaboration:
Females: need two recessive alleles to express it (xx) and can be carriers (Xx).
Males: one affected X means they have the condition—no carriers.
Q10: What is a karyotype?
A: A pictorial display of all chromosomes arranged in pairs.
Elaboration: It helps identify genetic abnormalities, such as trisomies.
