Lecture 11 Flashcards
What are other names for sex chromosomes?
Heterosomes
Allosomes
Gonosomes
What is the nomenclature for female chromosomes?
44A + XX
What is the nomenclature for males chromosomes?
44A+XY
What is the sex of plants?
Many have both male and female reproductive organs in a single flower, while others have sexual dimorphism
What is a Hermaphrodite is plants?
Plants that have both male (stamen) and female (carpel) reproductive organs
How do Animal hermaphrodites reproduce?
Some can self fertilize while others require 2 partners
What is the sex of Animal Hermphrodites?
Some are male or females at different times on their life cycle
What is sex determined by in Animals?
Sex determination is associated with and caused by a pair of sex chromosomes that genetically determine sex
What do some species use to determine sex that is not based on sex chromosomes?
Environmental factors
What is a Monoecious plant?
A plant with male and female flowers that are separate from each other
What are Perfect flowers?
Those with male and female parts in the same flower
What is a Dioecious plant?
Plants that have literal separate males and females
What is Sequential Hermaphroditism?
In anemone fish when a dominant female dies, the dominant male becomes the female and the next male in line becomes dominant
What is Simultaneous Hermaphroditism?
Individuals possess fully functional male and female gonads
What is Sequential Hermaphroditism?
Fish change sex sometime during its life, either from male to female or from female to male
What is Protogyny?
Female to male
What is protandry?
Male to female
How is sex determined in alligators?
By it environment. Temperatures of 30° produce all females, temperatures of 34°produce males
What is Parthenogenesis?
In some species the females lay fertile eggs - no males required
What are the characteristics of sex chromosomes?
Usually chromosomes that are morphologically distinct from each other. Their presence or a scenes determined the sex of the individual
What are the Sex chromosomes in females known as?
XX homogametic
What are the sex chromosomes in males known as?
XY heterogametic
What organisms is the XY system used in?
Mammals, and some insects and plants as well
What are heteromorphic sex chromosomes?
Sex chromosomes that look different from each other