Download Exam 2 Study Guide

HUMAN GENETICS
Exam 2 Study Guide
Week 6: Complex Inheritance
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Explain why polygenic traits can be expressed by a bell curve. What would happen to
the bell curve over several generations if you only mated individuals from one extreme
on the curve (see our racehorse example from class)?
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Explain how the additive effect of several genes can result in a polygenic trait (see our
speed example from class).
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Define epistasis and give an example of one trait that is epistatic to another.
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What is the evidence that obesity is multifactorial and not completely genetic?
Explain why human height is considered to be a multifactorial trait. (What is the
environmental component?)
Define epigenetics, and explain what effect imprinting (or methylation) has on whether
or not a gene is turned on or off.
Week 7: Genetics of Sex and Gender
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Explain why males are hemizygous for X-linked traits.
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Be able to complete and interpret a Punnett square for an X-linked recessive trait (such
as colorblindness).
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Explain how human sex ratios change from birth, through adolescence, and finally into
old age. What is responsible for the shift in favor of females as we age?
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Describe the two methods that can be used to choose the sex of a baby (sperm sorting
vs. preimplantation genetic diagnosis).
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Explain what SRY is and how it was discovered. What is the evidence that supports the
idea that SRY is important in the development of males.
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Be able to predict the phenotypes of people with the following mutations (note: two of
these should be normal):
List and describe any key facts about the sex chromosomes found in males and
females.
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XX without SRY
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XY with SRY
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XX with SRY
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XY without SRY
Week 8: Reproduction in Males
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Be able to identify the following on figures and briefly explain their function:
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testis
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seminiferous tubule
updated 3/30/13
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HUMAN GENETICS
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epididymis
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vas deferens
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seminal vesicle
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prostate gland
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bulbourethral gland
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penis
Exam 2 Study Guide
Explain the process of spermatogenesis
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Where it occurs (in the body)
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How cells physically move towards the lumen of the seminiferous tubule
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How many sperm are produced from a single spermatogonium
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The structure of a mature sperm
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What role Sertoli cells play
Explain the roles of the following hormones in spermatogenesis:
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LH and FSH
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testosterone
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Be able to list a couple of the sexual characteristics controlled by testosterone
(other than making sperm; i.e., body hair growth, deepening voice, aggressive
behavior, etc.)
For each of the following male reproductive system disorders, be able to: (1) explain
what the condition is, (2) identify the organ(s) involved, (3) list 1-2 risk factors, and
(4) briefly describe what treatment options are available:
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cryptorchidism (undescended testes)
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hypospadias
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impotence/erectile dysfunction
• BPH and prostate cancer
Identify the three leading causes of male infertility.
Be able to define the following:
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insemination
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in vitro fertilization
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ICSI (intracytoplasmic sperm injection)
Week 9: Reproduction in Females
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Be able to identify the following on figures and briefly explain their function:
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ovary
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oviduct/Fallopian tube
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HUMAN GENETICS
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uterus
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endometrium
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cervix
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vagina
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clitoris
Exam 2 Study Guide
On the figure of the female reproductive system used in class, be able to show/explain:
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where sperm are deposited during ejaculation
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the path that sperm travel to the oocyte
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show where fertilization occurs
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show where implantation occurs
Explain the process of oogenesis
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Where it occurs (in the body)
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When it begins in a female’s life
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How many oocytes are produced from a single oogonium
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When the “stops” in meiosis occur (prophase I, metaphase II)
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What the term ovulation refers to
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What happens to the remaining follicle cells after ovulation
Explain the roles of the following hormones during the female reproductive cycle
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estrogen
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progesterone
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Explain the relationship between estrogen and progesterone and the thickening of
the uterine lining.
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Explain the corpus luteum’s role as a hormone-secreting structure.
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What is the current trend for the age of girls (and boys) entering puberty? What is a
possible cause for this?
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Explain what menopause is and what some of the effects of menopause are.
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For each of the following female reproductive system disorders, be able to: (1) explain
what the condition is, (2) identify the organ(s) involved, (3) list 1-2 risk factors, and
(4) briefly describe what treatment options are available:
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pelvic inflammatory disease (PID) and toxic shock syndrome
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prolapse
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endometriosis
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polycystic ovarian syndrome
• ovarian cancer
Identify the leading causes of female infertility.
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HUMAN GENETICS
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Exam 2 Study Guide
Be able to define the following:
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use of donors
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surrogacy
(Note: some of the treatments for male infertility, such as insemination and IVF, can be
used for females, as well.)
updated 3/30/13
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