lecture28_SexDeterminationEnvironmentalandGenetic

lecture28_SexDeterminationEnvironmentalandGenetic - Sex...

Info iconThis preview shows pages 1–9. Sign up to view the full content.

View Full Document Right Arrow Icon
1 Sex Determination Environmental And Genetic Part I
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
2 from Chapter 26 Klaus Kalthoff Environmental and Genetic
Background image of page 2
Location dependent sex determinations in worms (sp. Bonellia ) Sex depends on where the larva settle. The female marine worm contains a long proboscis (1 meter long). If a larva settles on the proboscis it enters the female’s mouth, migrates to the uterus, and differentiates into a 1-3 mm long symbiotic male that fertilizes the female eggs. If the larva settles on a rock (not on the proboscis) then it will differentiate into a female. Some chemical in the proboscis masculinizes.
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
4 Temperature dependent sex determination in reptiles Lizard eggs incubated at lower temperature (22-27 ° C) produces embryos of a single sex (female). Eggs incubated at higher temperatures (> 30 ° C) produce eggs of the other sex (male). The opposite is true of turtles. In alligators temps below 30 ° C produce female alligators whereas those above 34 ° C produce male alligators.
Background image of page 4
5
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
6
Background image of page 6
7 Determination of sex in mammals is Chromosomal
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
8 Turner’s syndrome (XO) individuals are phenotypically female Klinefelter’s syndrome (XXY) extra X chromosome - individuals are phenotypically male Determination of sex in mammals is Chromosomal XX individuals are female and XY individuals are male. The Y chromosome determines the sex of an embryo.
Background image of page 8
Image of page 9
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page1 / 35

lecture28_SexDeterminationEnvironmentalandGenetic - Sex...

This preview shows document pages 1 - 9. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online