Transcript Topic 2

Topic 2:
The Endocrine System
2.1 Systems of chemical mediation and communication
2.2 A comparison of endocrine and exocrine cells (Part 1)
2.2 A comparison of endocrine and exocrine cells (Part 2)
Figure 3.12: Exocytosis, p. 78.
Extracellular
fluid
Plasma membrane
SNARE
Vesicle
SNARE
Molecules to
be secreted
Secretory vesicle
Cytoplasm
(a)
(b)
Human Anatomy and Physiology, 7e
by Elaine Marieb & Katja Hoehn
Copyright © 2007 Pearson Education, Inc.,
publishing as Benjamin Cummings.
Figure 3.13: Clathrin-mediated endocytosis, p. 79.
Extracellular
fluid
Cytoplasm
Clathrincoated
pit
Ingested
substance
Exocytosis
of vesicle
contents
Clathrin
protein
Cytoplasm
Bacterium
or other
particle
Clathrin
protein
Pseudopod
(b) Phagocytosis
Endosome
Uncoated
vesicle
3
Transcytosis
2
To lysosome
Uncoating
for digestion
Uncoated and release
vesicle
of contents
fusing with
endosome
(a) Clathrin-mediated endocytosis
Human Anatomy and Physiology, 7e
by Elaine Marieb & Katja Hoehn
Extracellular
fluid
Recycling of
membrane and
receptors (if present)
to plasma membrane
1
Detachment
of clathrincoated
vesicle
ClathrinPlasma
coated
membrane vesicle
Extracellular
fluid
Plasma
membrane
Membrane
receptor
Clathrin
protein
(c) Receptor-mediated endocytosis
Copyright © 2007 Pearson Education, Inc.,
publishing as Benjamin Cummings.
2.3 The major endocrine glands and tissues in humans
Figure 16.3: PIP second-messenger mechanism of amino acid-based hormones, p. 608.
Extracellular fluid
Hormone
DAG
1
4
2
Receptor Gq
Catecholamines
TRH
ADH
GnRH
Oxytocin
GTP
3
GTP
GTP
GDP
5
IP3
Phospholipase C
Inactive
protein
kinase C
Triggers responses
of target cell
5
Endoplasmic
reticulum
Cytoplasm
Human Anatomy and Physiology, 7e
by Elaine Marieb & Katja Hoehn
Active
protein
kinase C
PIP2
6
Ca2+
Ca2+-calmodulin
Copyright © 2007 Pearson Education, Inc.,
publishing as Benjamin Cummings.
2.4 The hypothalamus
2.5 The pituitary gland
2.6 Hypothalamic communication with the anterior and posterior pituitary
2.7 The thyroid gland (Part 1)
2.7 The thyroid gland (Part 2)
Figure 23.20
2.8 The pancreas (Part 1)
Six primary hormones produced by the pancreas:
1. Insulin - causes cells in the liver, muscle and fat to uptake gluclose from
the blood to store as glycogen in muscle and liver.
2. Glucagon – released when blood glucose levels are too low , causing the
liver to convert stores of glycogen into glucose. The glucose is released into
the bloodstream
3. Somatostatin - suppresses the release of various gastrointestinal hormones.
4. Ghrelin – hunger stimulating hormone
5. Pancreatic polypeptide – regulates secretion of the endocrine and exocrine
chemicals of the pancreas. In humans , secretion is increased after a
protein meal, fasting, exercise.
6. Amylin - functions as a synergistic partner to insulin, but seems to be more
intimately involved in determination of the glycemic index than insulin in
readings related to A1C.
2.8 The pancreas (Part 2)
Alpha cells will produce glucagon.
Beta cells will produce insulin and amylin.
Delta cells will produce somatostatin
PP cells will produce pancreatic polypeptide.
Epsilon cells will produce ghrelin.
2.9 The adrenal glands (Part 1)
2.9 The adrenal glands (Part 2)
2.10 The pineal gland (Part 1)
2.10 The pineal gland (Part 2)
This is the point where we have
concluded Chapter 2 materials
relevant to lecture exam #1. The
remainder of the materials that follows
will be part of lecture exam #2.
Figure 27.1
Figure 27.3a
2.11 The testes
Figure 27.11
Figure 27.12a
Figure 27.12b
Figure 27.14a
2.12 The ovaries (Part 1)
2.12 The ovaries (Part 2)
2.13 Protein and peptide hormone receptors
2.14 A tyrosine kinase receptor
Active site
Amino acids
+
Enzyme (E)
Substrates (S)
Enzyme-substrate
complex (E-S)
H2O
Free enzyme (E)
Peptide bond
Internal rearrangements
leading to catalysis
Dipeptide product (P)
Human Anatomy and Physiology, 7e
by Elaine Marieb & Katja Hoehn
Copyright © 2007 Pearson Education, Inc.,
publishing as Benjamin Cummings.
2.15 A G protein
2.16 Signal amplification by second messengers
2.20 Known amino acid sequences of releasing hormones (Part 1)
2.20 Known amino acid sequences of releasing hormones (Part 2)
2.21 Primary structures of species-specific forms of GnRH
2.23 Primary structure of the nonapeptides secreted by the posterior pituitary
2.25 Milk letdown is mediated by oxytocin (Part 1)
Figure 27.17
2.25 Milk letdown is mediated by oxytocin (Part 2)
2.26 Thyroid hormone synthesis
2.28 Steroid chemical structure and nomenclature
2.29 Steroid hormone receptors are generally located in the cytosol or nucleus of a cell
2.30 Biochemical pathways in steroid formation (Part 1)
2.30 Biochemical pathways in steroid formation (Part 2)
2.31 Androgens (Part 1)
2.31 Androgens (Part 2)
2.32 Estrogens (Part 1)
2.32 Estrogens (Part 2)
2.33 Epinephrine, norepinephrine, and dopamine are catecholamines
2.35 Models of negative and positive feedback
2.36 Negative feedback
Box 2.1(A) Life cycle of the silkworm moth
Box 2.2 The Discovery of Secretin