The bi-potential external genitalia are those that exist before the the genitalia differentiate into male or female genitalia under the influence of various hormones. The structures that are eventually derived from the 3 main parts of the undifferentiated external genitalia are as follows for females and males:
Female
Male
brain and spinal cord
homologous structures
it means problems which come from outside of something. External means coming or derived from an outside source.
Structures derived from the hindgut are:distal third of the transverse colondescending colonsigmoid colonrectumupper portion of the anal canal
Structures which are derived from the foregut are:stomachlivergall bladderpancreasduodenal cap, descending duodenum (1st and 2nd parts of the duodenum)
nerves
Read page 12 of the lab manual... Derived is more resent than conservative, therefore it would have appeared later than conservative.
Yes, homologous structures have common bone and muscle structures suggesting that they came from an common ancestor while analogous structures do not share any similarity in features, suggesting that they derived from two separate origins.
Chromosomes
transformational grammar
Structures which are derived from the midgut are:horizontal and ascending duodenum (3rd and 4th parts)jejunumiliumcecumascending colonfirst two-thirds of the transverse colon
lining of the lungs, the brain or the kidneys