Endocrine System: Pancreas & Control of Body Energy

Insulin

An increase in the number of GLUT4 transporters in muscle and adipose cell membranes is produced by the actions of the hormone _________.

hypoglycemia

An individual with abnormally low plasma glucose levels is said to have _________.

HDLs (high-density lipoproteins)

Lipoproteins that transport excess cholesterol from other tissues to the liver are known as ___________.

-ingested dietary cholesterol -cholesterol synthesized in the liver and other organs

What are the two sources that contribute to plasma cholesterol?

- It increases blood glucose levels -It increases lipolysis -it increases gluconeogenesis

What effects does growth hormone have on metabolism?

Liver cells have the correct enzyme (glucose-6-phosphatase).

What enables the liver to break down its glycogen to release glucose into blood, whereas skeletal muscle does not?

Decrease; decrease

When a person undergoes starvation and the adipocytes begin to shrink, leptin secretion ______ and that results in a(n) ______ in basal metabolic rate.

An increase in liver glycogen stores and export of very low density lipoprotein into the blood.

When excess amino acids and glucose are taken into the liver and processed during the absorptive state, what is the net result?

Hypothalamus

Where is Neuropeptide Y produced?

Pancreas

Where is insulin produced

Adipose Tissue

Where is leptin produced?

liver, adipose, cardiac muscle, skeletal muscle

Which four tissues are the major sites of action of insulin?

Glucagon, Growth hormone, insulin, cortisol

Which hormones are important mediators of metabolic changes that occur to switch the body back and forth between the fed and fasting states?

Increased plasma ghrelin

Which of the following increases hunger?

-the brain uses both glucose and ketones for energy -glycogen, fat, and protein synthesis decreases, and net breakdown occurs -lipolysis releases fatty acids to the blood, and beta oxidation by the liver produces ketones

Which of these metabolic rearrangements occurs in response to a prolonged fast?

Insulin, Leptin, Cholecystokinin

Which three of the following inhibit hunger?

small intestine, liver

Which tissues make large amounts of cholesterol which can then enter the blood?

fat, triglycerides, lipids, or fatty acids

While adipocytes also catabolize glucose for energy, the most important fate of glucose is them during the absorptive state is its transformation to _________.

Chylomicrons

Absorbed triglycerides are transported from the GI tract to the liver in lipid-protein complexes called ____________.

Glycerol, fatty acids

Lipocytes of adipocyte triglycerides release _________ & ___________

1 gram

A calorie is the energy required to raise the temperature of __________ of water from 14.5 to 15.5 degrees Celsius

1000

A kilocalorie contains __________ calories.

Obese

A person with a body mass index greater than 30 kg/m2 would be categorized as ______.

Ghrelin

A polypeptide hormone synthesized and released primarily from enteroendocrine cells in the stomach and which increases hunger is ___________.

ghrelin

A polypeptide hormone synthesized and released primarily from enteroendocrine cells in the stomach and which increases hunger is ___________.

Proteins, fats, carbohydrates

A typical mean contains all three of the major energy-supplying good groups. What are they?

Triglycerides

Adipocytes are the site of storage of ___________.

Lipoprotein lipase

Because of their size, VLDLs in the blood do not readily cross capillary walls. Instead, their triglycerides are hydrolyzed mainly to monoglycerides (glycerol linked to one fatty acid) and fatty acids by the enzyme ________ ___________.

monosaccharides

Carbohydrates are absorbed from the intestine into the blood primarily in the form of molecules known as ___________.

energy, calories, or ATP

Carbohydrates, fat, and protein provide ____________ needed for body functions while vitamins and minerals do not.

glycerol & Fatty acids

Catabolism of triglycerides in adipocytes yields the breakdown products __________ & ______________ ________.

-deficit of cortisol secretion -excess insulin secretion

Causes of hypoglycemia?

amino acids

Digested proteins are absorbed from the intestine into the bloodstream primarily in the form of __________ __________.

ketones; glucose

During a prolonged fast, which two fuels are directly used by the brain to supply energy?

Absorptive

During the ___________ state, cellular uptake of glucose and amino acids occurs, with increases in the synthesis of glycogen, protein, and triglycerides

Glycogen and ATP

During the absorptive state of metabolism, glucose is used to form what in skeletal muscle?

Glucose or carbohydrates

During the absorptive state while ingesting a balanced meal, the primary energy source for cells of the body is ____________.

Permissiveness

During the alterations required in adjusting metabolism during fasting states, cortisol plays what role?

glycogen; glucose-6-phosphate

During the postabsorptive state, liver _____ is first broken down into ________________, which is then enzymatically converted to glucose and released into the blood.

Increase in appetite, decrease in BMR (basal metabolic rate)

Effects of decreased leptin secretion

-increases gastric motility and acid production -decreases the breakdown of fat -stimulates appetite -stimulates neuropeptide Y release

Effects of the hormone Ghrelin

Postabsorptive

Energy substrates like glucose are released from body energy stores during the __________ state.

Absorptive

Energy substrates, such as glucose, fatty acids, and amino acids are processed into larger molecules that can be stored in the body during the ___________ state.

Stimulates

Epinephrine ___________ the activity of hormone-sensitive lipase.

Increasing

Epinephrine has the effect of ___________ blood glucose levels.

increases

Epinephrine mediates the fight-or-flight response, so when its secretion increases it ______ the concentration of glucose and fatty acids levels in the blood.

Energy stored = Energy from food intake − (Internal heat produced + External work)

Equation that indicates the energy stored

decrease; increase

Exercise produces a(n) _________ in insulin secretion and a(n) ____________ in glucagon secretion

Lipoproteins

Fat synthesized by the liver from glucose is packaged into _____________.

the stomach; increase hunger

Ghrelin is a hormone secreted by ______, and it acts to ______.

stomach

Ghrelin is produced in the

Neuropeptide Y

Hunger is stimulated by a neurotransmitter called ______, which is a hypothalamic neurotransmitter. Multiple choice question. neuropeptide Y

Formation of glucose from precursors such as amino acids and glycerol

Gluconeogenesis is the term describing the _________________.

liver and muscle/skeletal

Glucose is stored as glycogen primarily in ________ and _________ cells

Glucagon

Glycogenolysis is stimulated in liver cells during the postabsorptive state by an increase of the hormone ____________.

Glucagon

Glycogenolysis, gluconeogenesis, and ketone synthesis are all processes directly stimulated by the hormone

Increase

Growth hormone promotes what change in blood glucose levels?

sympathetic

Hepatic glycogenolysis is stimulated by activation of the _________ division of the autonomic nervous system.

atherosclerosis

High plasma concentrations of cholesterol enhance the development of _________________, the arterial thickening that may lead to heart attacks, strokes, and other forms of cardiovascular damage.

-glycogenolysis -lactate produced in muscle -gluconeogenesis using amino acids as substrates -glycerol resulting from lipolysis

Identify the processes that contribute to sustaining blood glucose during the postabsorptive state.

hypoglycemia

If an individual has a cortisol deficiency, during fasting the individual would develop ____________

metabolism increases, tending to move them back towards a body-weight set point

If subjects are over-fed and an increase in body weight occurs, __________________.

GLUT (glut-4)

In skeletal muscle cells and adipocytes, an increases insulin concentration stimulates cytoplasmic vesicles that contain a particular type of glucose transporter in their membranes to fuse with the plasma membrane. This transporter is known as ___________-4

lipolysis

In times of fasting, _______ occurs.

Liver and skeletal muscle

In what tissue is glucose stored as glycogen?

Growth Hormone

Increased gluconeogenesis, increased muscle protein synthesis, increased lipolysis, and decreased glucose uptake by muscle and adipose tissue are metabolic effects of which hormone?

Insulin.

Increased glycogen formation, decreased gluconeogenesis, increased protein synthesis, and decreased lipolysis are caused by secretion of _________.

an increase; inhibits

Increased ingestion of cholesterol causes ____________ in plasma cholesterol, which ____________ cholesterol synthesis by the liver.

Absorptive State

Ingested Nutrients leave the gastrointestinal tract and enter the blood during the ____________.

Absorptive State

Ingested nutrients enter the blood from the gastrointestinal tract.

liver

Ingestion of cholesterol increases its plasma levels, which inhibits synthesis of cholesterol by the ____________, thereby helping to maintain cholesterol homeostasis

Signal transduction

Insulin binds to specific receptors on the plasma membranes of its target cells. This binding triggers __________ ___________ pathways that influence transport proteins and intracellular enzymes of the target cell.

binding to plasma membrane receptor

Insulin initiates a signal transduction cascade within target cells by ____________.

absorptive; postabsorptive

Insulin is the most important controller of organic metabolism. Its secretion-- and therefore, its plasma concentration-- is increased during the ___________ state and decreased during the ____________ state.

neuropeptide Y

Leptin acts on the hypothalamus to inhibit the secretion of _________.

Joules

One calorie is equal to 4.184 __________

Glucose

Other than ingested triglycerides, the substrate _______________ is most typically broken down and used for the synthesis of fatty acids in adipose tissue

-Glycerol 3-phosphate and fatty acids are combined to form triglycerides in liver -glycerol 3-phosphate and fatty acids are combined to form triglycerides in adipose tissue -glucose is converted to glycogen in skeletal muscle cells -amino acids are catabolized into NH3 and alpha-keto acids in liver

Processes favored during the absorptive state

Increase in leptin, insulin, body temp, plasma glucose and the stretch of the stomach and duodenum

Signals of satiety

True

T or F: Cholesterol is both ingested in animal products and synthesized by cells of the body.

False, BMI is the weight in kilograms divided by the square of the height in meters.

T/F: Body mass index is defined as the weight in kilograms divided by the height in meters.

True

T/F: During metabolism, more than half of the energy released from organic molecules produces heat rather than work.

True

T/F: When considering total energy expenditure, excretion of nutrients typically does not need to be included because the loss is negligible in a healthy person.

metabolic rate

The amount of energy liberated in the body per unit of time, expressed in such terms as kcal/hour or kcal/day is called the

Glucose

The body's primary energy source during the absorptive state is __________.

lipolysis

The breakdown of triglyceride into circulating forms that can be used by cells for energy is called ___________.

Postabsorptive state

The effects of exercise on metabolism are similar to those of the _________.

capillary endothelial cells

The enzyme lipoprotein lipase found on the blood-facing surface of __________.

1. Consumption of a meal rich in carbohydrate 2. Increase in plasma glucose concentration 3. Rapid increase in insulin secretion 4. Increase in plasma insulin concentration 5. Increase in glucose transport from extracellular fluid into cells 6. Restoration of plasma glucose to normal

The following are steps associated with the plasma glucose control over insulin secretion. Place them in the correct sequence, starting with the first step at the top.

Postabsorptive State

The gastrointestinal tract is empty of nutrients and the body's own stores must supply energy.

helps to maintain body temperature

The heat released from organic molecules during cellular metabolism ___________.

Glucogenolysis

The hydrolysis of glycogen is called _______________.

Absorptive; postabsorptive

The levels of insulin in plasma increase during the ________ state and decrease during the ____________ state.

VLDL or very low density lipoproteins

The lipid-protein aggregates synthesized by the liver from glucose during the absorptive state are secreted into the blood as ____________.

HDL

The lipoprotein most likely to be referred to as "good cholesterol" is ___________.

the liver

The main source of glucose during the first few hours of the postabsorptive state is __________.

Ghrelin

The major function of hormone X is is to increase hunger by stimulating neuropeptide Y. The name of hormone X is ______________.

Insulin; Glucagon

The most important controls of these transitions from feasting to fasting, and vice versa, are two pancreatic hormones: _________ and __________.

Synthesis of triglycerides

The primary fate of glucose in adipocytes during the absorptive state is in the ___________.

Appetite

The psychological desire to eat food is referred to as

Triglycerides

The released fatty acids from plasma chylomicrons then diffuse into adipocytes and combine with glycerol 3-phosphate, synthesized in the adipocytes from glucose metabolites, to form ______________.

Satiety

The sense that enough food or beverages have been consumed to satisfy hunger is called ___________.

metabolic rate

The total energy expenditure of the body per unit of time is known as the ___________ ______.

LVDLs; chylomicrons

Two sources of the fatty acids that are used in the synthesis of triglycerides in adipocytes are ________ produced by the liver, and _____________ produced in the intestines from ingested fatty acids.

Gluconeogenesis

the "creation of new glucose"

Negative

the relationship between blood glucose levels, insulin secretion, and insulin action is an example of a homeostatic process regulated by ________ Feedback.