Anatomy & Physiology Lab Exam 1 Study Guide
The Endocrine System:
Production and Stimulation of Hormones:
1. TRH: hypothalamus releases thyrotropin-releasing hormone
2. TSH: anterior pituitary releases and produces thyroid-stimulating hormone
- Stimulates the thyroid to produce Thyroxine
3. Thyroxine: controls metabolic rate (measures Oxygen uptake which gets converted to
mL of O2 per Kg per Hour
● Thyroid hormone levels are low, so they secrete more TRH and TSH, which
stimulates the thyroid to make more hormones.
● Thyroid hormone levels are too high, so they secrete less TRH and TSH, which
reduces hormone production by the thyroid.
Negative Feedback Example:
● The stimulus is the decrease in T3 and T4 concentrations in the blood/low body
temperature. The hypothalamus releases Thyroid Releasing Hormone and the Anterior
Pituitary releases TSH. The thyroid gland follicles release T3 and T4 so that
homeostasis can be restored.
● Insulin lowers blood glucose when levels are too high and glucagon raises blood glucose
when levels are low.
Rat Questions: ml of o2 per kg per hour
1. Which rat had the fastest basal metabolic rate (BMR)?
- The normal rat.
2. What will occur metabolically with a rat that has had its thyroid gland removed?
- The BMR would decrease.
3. What happens to the metabolic rate of a rat with no thyroid gland when thyroxine is
injected into the rat?
- The BMR would increase.
4. If an animal had been thyroidectomized, what hormone(s) would be missing in its blood?
- Thyroxine and Calcitonin
, Anatomy & Physiology Lab Exam 1 Study Guide
5. What was the effect of TSH injections on the normal rat’s BMR?
- The metabolic rate went up and the baseline was a lot lower.
6. What was the effect of PTU injections on the normal rat’s BMR?
- It slowed the metabolic rate, compared to the normal baseline. PTU inhibits the
production of thyroxine.
7. An injection of TSH to an otherwise normal animal will cause…
- Goister development
Insulin & Glucose:
- Both produced by the pancreas (which maintains homeostatic blood glucose levels)
- Insulin decreases blood glucose
❏ Released by the beta cells in the pancreas in response to rising glucose in the
bloodstream (hyperglycemia)
- Glucagon increases blood glucose levels due to the breakdown of glycogen and the
release of glucose into the bloodstream
❏ Released by Alpha cells to stop blood sugar levels dropping too low
(hypoglycemia)
❏ Glucose is stored in the liver and bloodstream.
➔ Normal fasting blood glucose: less than 110 mg/dl
Diabetes:
● Type 1: pancreas doesn’t produce enough Insulin (juvenile diabetes)
● Type 2: body cells don’t respond to insulin (triggered by obesity)
Prediabetes or Borderline Impairment: 110-126 mg/dl
Diabetes: 126 or above mg/dl
➔ Gestational Diabetes: diagnosed during pregnancy, can start when the mother’s body is
unable to make & use all the insulin it needs for pregnancy
How do you determine Blood Glucose Levels using the Standard Curve?
- You measure optical density & read the curve to determine glucose levels.
The percentage of glucose taken during a meal & storing it as glycogen?
- 75%
A male patient has had successive fasting plasma glucose reading of 115, 110, and 122 mg/dl.
The healthcare provider will inform him that:
- He appears to have impairment or borderline impairment of insulin-mediated glucose
uptake by his cells
Hematocrit & Hemoglobin:
Hematocrit: percentage of Erythrocytes (Red Blood Cells) in a sample of whole blood
- Normal Hematocrit for Males: 42-52%
- Normal Hematocrit for Females: 37-47%
➔ Anemia causes: low or depressed hematocrit from hyperthyroidism, cirrhosis, etc.
➔ Polycythemia causes: high hematocrit from living at high altitudes & congestive heart
failure
Hemoglobin: a protein found in red blood cells which is necessary for the transport of oxygen
from the lungs to the cells of the body.
- Normal Hemoglobin for Males: 13.5-18 g/100ml
The Endocrine System:
Production and Stimulation of Hormones:
1. TRH: hypothalamus releases thyrotropin-releasing hormone
2. TSH: anterior pituitary releases and produces thyroid-stimulating hormone
- Stimulates the thyroid to produce Thyroxine
3. Thyroxine: controls metabolic rate (measures Oxygen uptake which gets converted to
mL of O2 per Kg per Hour
● Thyroid hormone levels are low, so they secrete more TRH and TSH, which
stimulates the thyroid to make more hormones.
● Thyroid hormone levels are too high, so they secrete less TRH and TSH, which
reduces hormone production by the thyroid.
Negative Feedback Example:
● The stimulus is the decrease in T3 and T4 concentrations in the blood/low body
temperature. The hypothalamus releases Thyroid Releasing Hormone and the Anterior
Pituitary releases TSH. The thyroid gland follicles release T3 and T4 so that
homeostasis can be restored.
● Insulin lowers blood glucose when levels are too high and glucagon raises blood glucose
when levels are low.
Rat Questions: ml of o2 per kg per hour
1. Which rat had the fastest basal metabolic rate (BMR)?
- The normal rat.
2. What will occur metabolically with a rat that has had its thyroid gland removed?
- The BMR would decrease.
3. What happens to the metabolic rate of a rat with no thyroid gland when thyroxine is
injected into the rat?
- The BMR would increase.
4. If an animal had been thyroidectomized, what hormone(s) would be missing in its blood?
- Thyroxine and Calcitonin
, Anatomy & Physiology Lab Exam 1 Study Guide
5. What was the effect of TSH injections on the normal rat’s BMR?
- The metabolic rate went up and the baseline was a lot lower.
6. What was the effect of PTU injections on the normal rat’s BMR?
- It slowed the metabolic rate, compared to the normal baseline. PTU inhibits the
production of thyroxine.
7. An injection of TSH to an otherwise normal animal will cause…
- Goister development
Insulin & Glucose:
- Both produced by the pancreas (which maintains homeostatic blood glucose levels)
- Insulin decreases blood glucose
❏ Released by the beta cells in the pancreas in response to rising glucose in the
bloodstream (hyperglycemia)
- Glucagon increases blood glucose levels due to the breakdown of glycogen and the
release of glucose into the bloodstream
❏ Released by Alpha cells to stop blood sugar levels dropping too low
(hypoglycemia)
❏ Glucose is stored in the liver and bloodstream.
➔ Normal fasting blood glucose: less than 110 mg/dl
Diabetes:
● Type 1: pancreas doesn’t produce enough Insulin (juvenile diabetes)
● Type 2: body cells don’t respond to insulin (triggered by obesity)
Prediabetes or Borderline Impairment: 110-126 mg/dl
Diabetes: 126 or above mg/dl
➔ Gestational Diabetes: diagnosed during pregnancy, can start when the mother’s body is
unable to make & use all the insulin it needs for pregnancy
How do you determine Blood Glucose Levels using the Standard Curve?
- You measure optical density & read the curve to determine glucose levels.
The percentage of glucose taken during a meal & storing it as glycogen?
- 75%
A male patient has had successive fasting plasma glucose reading of 115, 110, and 122 mg/dl.
The healthcare provider will inform him that:
- He appears to have impairment or borderline impairment of insulin-mediated glucose
uptake by his cells
Hematocrit & Hemoglobin:
Hematocrit: percentage of Erythrocytes (Red Blood Cells) in a sample of whole blood
- Normal Hematocrit for Males: 42-52%
- Normal Hematocrit for Females: 37-47%
➔ Anemia causes: low or depressed hematocrit from hyperthyroidism, cirrhosis, etc.
➔ Polycythemia causes: high hematocrit from living at high altitudes & congestive heart
failure
Hemoglobin: a protein found in red blood cells which is necessary for the transport of oxygen
from the lungs to the cells of the body.
- Normal Hemoglobin for Males: 13.5-18 g/100ml
