ANSC 3122 Lecture Notes - Lecture 4: Sex Cords, Urinary System, Cryptorchidism
Document Summary
Embryogenesis: embryo earlier in the pregnancy, fetus later in the pregnancy. Definition of sex: the sum total of morphological, physiological, and psychological differences that distinguish a male from a female, genotypic sex. Determined at ovulation: genetically we are always (except for anomalies) xx or xy (genotype) Anatomy can be more ambiguous (phenotype: sex determination. Sex differentiation (the development in the male or female direction) Sex ratio: the percent males or number of males per 100 females, usually approximates 50:50, primary sex ratio at fertilization, secondary sex ratio at parturition/birth, tertiary sex ratio at puberty. Differentiation: during embryogenesis, cells differentiate from discrete germ layers into organs. + hypothalamus & both lobes of pituitary gland. + teeth: differentiation is the process by which a group of unspecialized cells develops into a functional recognizable group of cells. Posterior lobe derived from neural tissue of the brain. Formed from a diverticulum (outcropping) from the floor of the brain.
