Lecture 9 - Start of Exam 2 Flashcards
Who discovered insulin
Frederick Banting
Charles Best
Who got the nobel prize for the insulin discovery
Frederick Banting
John McLeod
With diabetes, glucose cannot _____
enter the cells
When glucose cant enter the cells, how does the body respond
mobilizing fats
(lipolysis)
Accumulation of ketone bodies due to diabetes leads to what
ketoacidosis
Can FFA make glucose
No
Can FFA enter the Krebs cycle
Not when carb sources are low
Why can FFA not enter Krebs cycle when carb sources are low
oxaloacetate is scavenged, which is the acetyl-CoA acceptor molecule
What is ketoacidosis
blood pH is lowered
what molecule turns into ketone bodies, and gives breath the sweet smell
acetoacetic acid
Why does a diabetic’s breath smell sweet
due to a build of of acetoacetic acid created from 2 acetyl-CoA when it cannot enter the Krebs cycle
What are the three signs of diabetes
Polyuria
Polydipsia
Polyphagia
What is polyuria
Excessive peeing
How is polyuria caused
Too much glucose in urine
Osmosis occurs, water follows (as does electrolytes)
Blood volume down, dehydration occurs
What is polydipsia
Being very thirsty all the time
How is polydipsia in diabetes caused
Dehydration due to polyuria stimulates hypothalamic thirst centers
What is polyphagia
excessive hunger
How is polyphagia caused in diabetes
the person is starving due to inability to use carbs
What type is the juvenile diabetes
Type 1
What type is the insulin dependant diabetes
1
What type of diabetes is the less common
1
What is type 1 diabetes caused by
A lack of beta cells
No insulin production
Name a theory that could cause type 1 diabetes
an autoimmune reaction that kills the beta cells
Is there a genetic component to type 1 diabetes
No
Why are there so many complications with insulin injections
You get a big spike of insulin at once, as opposed to little amounts released by your body to maintain homeostatic range
What is one of the biggest issues associated with diabetes/insulin injections
nerve issues
What is the most common form of diabetes
Type 2
Is there a genetic component to type 2 diabetes
Yes, a strong one
Do type 2 diabetics produce insulin
Typically yes, but in smaller amounts or the receptors are desensitized
Do only overweight and sedentary people get type 2 diabetes
No, it just makes you more predisposed to it
Ketoacidosis is not a major problem for what type of diabetes
Type 2
What type of vitamins does the liver store
Fat soluble
K A D E and B12 but its water soluble
What is the primary site for B oxidation
Liver
What generates ketone bodies from acetyl-CoA
The liver
What are the four kinds of lipoproteins
Cholymicrons
VLDL
LDL
HDL
What kind of lipoprotein is mostly triglyceride
Cholymicrons
Less density is caused by more or less lipids?
More
More lipids = lower density
What type of lipoprotein carries the least lipids
HDL
What are the 4 main components of lipoproteins
Triglycerides (lipids)
Phospholipids
Cholesterol
Protein
Where are VLDL made primarily
Liver
What is the VLDL main role
transport triglycerides to peripheral tissues (adipose mainly)
what do VLDL turn into after they unload the triglycerides
LDL
what is the primary role of LDL
deliver cholesterol to peripheral tissues
What is the “bad” lipoprotein
LDL
What is the primary purpose of the HDL
transport cholesterol from peripheral tissues to the liver (to be broken down)
What level of cholesterol is considered excess
over 200mg/dl
What is the high risk form of LDL
lipoprotein (a)
What stimulates liver synthesis of cholesterol
saturated fatty acids
what does saturated fatty acids stimulated and inhibit
stimulates liver synthesis of cholesterol
inhibits cholesterol excretion
What do unsaturated fatty acids promote
catabolism and excretion of cholesterol
What do trans fats stimulate and inhibit
stimulates increased in LDL (bad) and inhibits HDL (bad thing, good lipoprotien)
What is the shape and location of the thyroid
Butterfly shape
On trachea
What is the largest pure endocrine gland in the body
Thyroid
What are the two lobes of the thyroid connected by
an isthmus
What is an isthmus
The part of the thyroid that connects the two lobes
What are follicles (thyroid)
hollow sphericle cells
What are thyroid follicles surrounded by
follicle cells
^cuboidal or squamous epithelial cells
what do follicle cells produce
thyroglobulin
What is thyroglobulin
a glycoprotein
What are follicles filled with
a colloid
What does colloid consist of
iodinated thyroglobulin
what is the precursor for thyroid hormone
iodinated thyroglobulin
iodinated thyroglobulin serves as the precursor for what
thyroid hormone
Where are parafollicular cells
interspersed between follicles
What produces calcitonin
parafollicular cells
What do parafollicular cells produce
calcitonin
what is the body’s major metabolic hormone
thyroid hormone
what is the primary secretory product of thyroid follicles
thyroxine T4
what is the most active thyroid hormone
triiodothyronine T3
The 4 and 3 on the thyroid hormones refers to what
number of iodine molecules
What is the name of T3
triiodothyronine
Name T4
thyroxine
What is triiodothyronine derived from
largely thyroxine at target cells
what tyrosines are combined to form T3 and T4
DIT (T1) and MIT (T2)
Where do tyrosine and iodine attach
in the colloid
What does lysosomal enzymes do in the thyroid
cleave T4 and T3 from thyroglobulin colloid - the iodinated tyrosine amino acids are A PART of thyroglobulin
T4 and T3 are transported in blood bound to what
thyroxine binding globulin
At target cells, most T4 is converted to waht
T3
Where is thyroxine binding globulin made
the liver
where does T3 and T4 bind
The thyroid hormone receptor (TR)
What form of thyroid hormone is more potent
T3 (10x more)
Why is T3 more potent
T4 doesnt bind to the TR (thyroid hormone receptor) quite as well
Where is the TR (thyroid hormone receptor)
In the nucleus of cells
What does T3/T4 do when binded
change expression of target genes
What stimulates secretion of TSH (thyroid stimulating hormone)
falling thyroid hormone levels
what makes TSH
anterior pituitary
What is the initial response of the tyroid gland due to TSH
secrete stored thyroid hormone
What is the second response of the thyroid gland to TSH
resynthesize thyroglobulin and replenish the colloid
what is unique about storage of the thyroid gland
it’s stored outside the cell
TH affects every cell of the body except (5 things)
adult brain
spleen
testes
uterus
thyroid gland
what is 3 major functions of TH
regulate metabolic rate/heat production
maintain blood pressure
Regulates tissue growth and development
what is calorigenic effect
higher metabolic rate
more heat
What is hypothyroidism
not enough TH
inadequate iodine causes what
an endemic goiter (big ass bump on the neck
how does an endemic goiter form
not enough iodine
follicle cells cannot make iodinate colloid
TSH increases to induce T3/T4 secretion
Makes even more colloid
severe hypothyroidism in infants is termed
congenital hypothyroidism
what is congenital hypothyrodism
severe hypotyroidism in infants
what is the most common form of hyperthyroidism
graves disease
how does graves disease work
you develop antibodies taht mimic TSH and wayyyy too much T3 and T4 comes out
What is tyrosine
An amino acid on the thyroglobulin glycoprotein
