Fig. 22-8
alpha and beta cells
Mostly, the pancreas is an exocrine gland involved in digestion.
Additionally, there is an endocrine portion, the islets of Langerhahns.
Alpha cells secrete glucagon.
Beta cells secrete insulin.

Fig. 22-9
fasted and fed states
When recently fed, glycogen, fat, and protein are stored; insulin dominates.
When fasting, glycogen is synthesized and glucose and ketones are manufactured; glucagon dominates.

Fig. 22-12
How insulin works (adipose and muscle cells)
After glucose binds its receptor (there is an intervening signal transduction cascade and) the GLUT-4 transporter is deployed to the membrane (in muscle).

Fig. 22.14
Insulin effects
High glucose causes insulin release.
There are many effects, all make sense in a state of plenty.
Mostly tissues like muscle move glucose out of the blood stream into the cells.

Fig. 22-15
Glucagon effects
Low glucose causes glucagon release.
There are many effects, all make sense in a state of deprivation.
Liver can supply glucose for the body.

Exam questions from 2005 - 2006 relating to this outline and the endocrine lab

When we say we are injecting "IP," what is IP?


In our lab, we injected insulin. Normally, insulin is supplied from what specific cell type in what specific organ?

beta cells of islets of Langerhahns in Pancreas

During fasting, what becomes of glycogen in the liver?

broken to glucose and released to blood for body use

What anesthetic was used in the endocrine experiment?

sodium pentobarbitol (Nembutal)

Why do you need to weigh your mouse?

to calculate anesthetic

Why would you go into shock if too much insulin were injected into you?

no glucose left for brain after tissues take it up

Why do you draw back on the syringe before injecting IP?

If there is fluid or blood, you are in organ

What hormone does the pancreas release during fasting?


The endocrine system uses/does not use ducts to secrete hormones.

Does not

Alpha cells in the pancreas secrete which peptide hormone?


Beta cells in the pancreas secrete which peptide hormone?


What type of receptor does insulin bind to thus initiating a signal trandsduction
cascade that allows insulin to affect the cell?

Receptor Tyrosine Kinase (RTK)

What does akinase do?


Which glucose transporter does muscle tissue use to transport insulin into the cell?


Which glucose transporter does the liver utilize to uptake glucose?


If the blood sugar level of an animal is 150 mg/dl, will the addition of glucagon make
next reading closer to 100 mg/dl or 200 mg/dl?

Closer to 200mg/dl

When there are high/low levels of glucose, glucagon is released.


We gave the injection of hormones and sedatives in the gut of the mouse, what is the
official name of this type of injection? (abbreviation or name will do).

I.P. or intraperitoneal.

What are the clusters of endocrine tissue in the pancreas collectively referred to as?

The islet of Langerhans.

In the fed state, name 2 types of biological molecules that are stored.

Sugars, fats, proteins.

What are the units of the blood plasma readings on the glucose meter?

mg/dl of plasma

Is glucose transport in the brain insulin dependent?


Where does your body get sugar from when you are in the fasting state (what is broken down?)

Stored Glycogen.

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