Chapter 5.docx

2 Pages
Unlock Document

Biological Sciences
Michelle Aarts

Chapter 5 –pituitary Hormones -Female Pit gland is much smaller than Males -Females becomes larger during pregnancy Anatomy of the Pituitary Gland - Also known as hypophysis - Composed of tissues derived from two diverse origins. Embryological origins of adenohypophysis and neurohypophysis are different - Composed of : adenohypophysis (anterior lobe) and neurohypophysis( posterior lobe) 1)Adenohypophysis - mostly glandular tissue -composed of pars distalis and tuberalis 2)Neurohypophysis - consists of neuronal processes that originate from neurons in the hypothalamus -composed of pars Nervosa Vascularisation and Innervation Size of each lobe of the pit gland varies between diff species and may reflect the hormonal output of the glands required for successful adaptation to a particular habitat The pituitary gland receives its blood supply from the superior and inferior hypophysial arteries Superior and Inferior branches of Superior hypophyseal artery penetrates the stalk and the hypothalamus Pars distalis - is vacularized by hypophyseal portalvessels that arise from capillary bed from the hypothalamus - No evidence that neurons innervate or otherwise influence cell activity of pars distalis Pars Nervosa - receives a separate blood supply from the inferior hypophysial artery - composed of axonal endings of neurons whose cell bodies are located in hypothalamic nuclei - hypothalamic nuclei: paraventricular nuclei and supraoptic nuclei - all hormones produced by the post. Lobe are released directly in to the efefretn portal veins to be carried through the systematic circulation to act at target tissues - some evidence indicates that some adenohypophyseal blood maybe shunted to the neurohypophysis pit hormones may be able to modify CNS function Cytotogical Methods Distinguish Different Pituitary Cell Types Pars distalis - cells are differentiated into somatotrophs, lactotrophs (mamotrophs), corticotrophs, thytotrophs, and gonadotrophs - ^ terms relate to hormonal product synthesized by each of these cells - The cell types can slo be referred to as acidophils, basophils and chromophobes depending on their affinity for ce
More Less

Related notes for BIOD27H3

Log In


Join OneClass

Access over 10 million pages of study
documents for 1.3 million courses.

Sign up

Join to view


By registering, I agree to the Terms and Privacy Policies
Already have an account?
Just a few more details

So we can recommend you notes for your school.

Reset Password

Please enter below the email address you registered with and we will send you a link to reset your password.

Add your courses

Get notes from the top students in your class.