Flashcards in Sex Development Deck (107)
Allows for introduction of genetic variation to propagate new genetic traits
Sexual reproduction benefits organisms who live in what type of environment
Exist in a constantly changing environment
Sexual reproduction benefits organisms who encounter what? And need to what?
Encounter bacteria, viruses, and parasites, and need to fend off disease
Sexual reproduction benefits organisms who need to purge what?
Sexual reproduction - 2 levels of variation
- each parent share's half genome via independent assortment
- recombination during meiosis
*note also that specific point mutations can occur that can confer advantage (or disadvantage) evolutionarily
What is sexual dimorphism?
The phenotypic difference between males and females -
includes reproductive organs as well as body habitus
Sex chromosomes anueploidy leads to
Disorders that don't have the normal number of X or Y chromosomes
Now matter how many X chromosomes you have, how many X chromosomes are active?
There is only one active X chromosome, no matter how many X chromosomes you have...
all only have one active X chromosome
Signs at birth
Prenatal cystic hygroma - cyst-like cavity filled with lymph
Puffy hands and feet
Coarctation of the aorta
Turner Syndrome - intelligence?
Normal - sometime targeted learning disabilities
Turner Syndrome - fertility?
Infertile due to non-functioning ovaries
Turner Syndrome - hormones?
Hormone dysfunction - need hormone treatment for secondary puberty
Turner Syndrome - distinctive features?
Low set ears - broad chest
Turner Syndrome - incidence?
1/2,500 newborn girls
Kleinfelter Syndrome - childhood and learning?
Can be seen -->
Delayed speech and language
Tendency toward being quiet
When does Kleinfelter become obvious?
Becomes more obvious as puberty - sometimes not even detected until infertility issues arise?
Kleinfelter genital issues?
Hypospadias - opening of urethra is on underside of penis
Kleinfelter - body habitus and hair?
Reduced facial and body hair
Feminized body habitus
Kleinfelter - incidence?
1/500 - 1/1000 newborn boys
What is 47, XYY?
What is Klinefelters chromosome constitution?
Jacobs syndrome clinical features (6)
Behavioral and emotional difficulties
Autism Spectrum disorders
Incidence of Jacobs Syndrome?
1/1000 newborn boys
So what is Jacobs vs. what is Klinefelters?
Jacobs = 47, XYY
Klinefelters = 47, XXY
What is 47,XXX called?
Triple X syndrome