Lab 5 Flashcards
What is the Glucose Experiment?
- Bread is made up of carbs that break down into sugars
- Complex carbs take a longer time to break down
- Foods that are harder to break down take longer to become metabolized like proteins and fats
- Metabolism changes most fats and proteins into sugars initially
- Complex carbs take a longer time to break down
- When we eat things, our blood sugar increases
- It increases at different rates based on the Glycemic Index of foods
- Easily metabolized carbohydrates and sugars have high glycemic indexes because they are metabolized quickly
- Complex carbs, proteins, and fats have lower glycemic indexes because they are metabolized slowly
What does glucose have to do with hormones?
- Insulin in blood brings blood sugar concentration down
- High glycemic index foods cause more insulin to be released in a short period of time
- Bread with peanut butter would be a longer and slower spike because peanut butter is metabolized more slowly due to fat content
Clinically, how do you see the relationship between blood glucose and hours?
Theres a technique that determines how well you can bring blood sugar down called an oral glucose tolerance test
What is homeostasis?
Maintains physiologic conditions with negative feedback
What is the negative feedback loop regarding homeostasis?
Most hormones operate within a negative feedback loop
Do hormones act with positive feedback loops?
Some hormones, such as those that eject things like babies operate in a positive feedback loop
What are autocrines?
Autocrines are a type of hormon signal that works on the cell that secretes it (the hormone)
What are paracrines?
Paracrines are types of hormone signals that signal a cell nearby to create something
What are endocrines?
Endocrines are types of hormone signals that are released in the bloodstream to signal a cell farther down
- Slow signal
- Long distance, entire blood stream
- Longer Lasting
What are neurocrines?
Neurocrines are released across synapses between neurons
- Fast signal
- Short distance, synapse
- Speedy effects
What are exocrines?
Exocrines are types of hormone signals that create hormones as well as enzymes
- Exterior of body
- Salivary, pancreas, sweat
Label the major endocrine organs
What is the Circadian Clock?
- Without the pineal gland, your body would operate on a 25 hour clock
- With the pineal gland, you secrete melatonin which is important to “turn off” the brain and suppress cortisol release from adrenal gland
- Some say melatonin supplements may change sleep-wake cycles via the placebo effect
***Melatonin makes you sleep and cortisol makes you awake
What’s the difference between an infant and an adult’s melatonin?
An infant may actually be able to absorb melatonin, where an adult could not due to a developed GI system
What gland is melatonin secreted from, what is the location of the target cells, and what are the hormone functions?
- Melatonin is secreted by the pineal gland
- Location of target cells: Brain
- Hormone function: Helps to set biological clock
What does the hypothalamus do?
- The hypothalamus creates “releasing hormones” that travel through the hypophyseal portal system to the anterior pituitary
- These releasing hormones cause the anterior pituitary to release other hormones that travel to effector organs
- The hypothalamus also produces 2 hormones that are released at the posterior pituitary that travel through the blood stream to effectors
Label the following image
- Posterior pituitary
- Hypothalamus
- Infundibulum
- Anterior pituitary
What is the difference between the anterior and posterior pituiatry?
- Basically: in the anterior pituitary there is a portal system and in the posterior pituitary there is just neurocrine
- Don’t need to know the releasing hormones (purple) just the red box
What is the hypophyseal portal system?
one capillary bed directly to another capillary bed
What gland is Human Growth Hormone (hGH) secreted from, what is the location of the target cells, and what are the hormone functions?
- Human Growth Hormone (hGH) is secreted by the anterior pituitary gland
- Location of target cells: Cartilage, bone, skeletal muscle, liver, and other body tissues
- Hormone function: Stimulates secretion of hormones that stimulate body growth and metabolism
What gland is Thyroid Stimulating Hormone (TSH) secreted from, what is the location of the target cells, and what are the hormone functions?
- TSH is secreted by the anterior pituitary gland
- Location of target cells: Thyroid gland
- Hormone function: Stimulates growth of thyroid gland and secretion of its hormones
What gland is Follicle Stimulating Hormone (FSH) secreted from, what is the location of the target cells, and what are the hormone functions?
- FSH is secreted by the anterior pituitary gland
- Location of target cells: Testes and Ovaries
- Hormone function: Stimulates sperm production; stimulates oocyte procution and estrogen secretion
What gland is Luteinizing Hormone (LH) secreted from, what is the location of the target cells, and what are the hormone functions?
- LH is secreted by the anterior pituitary gland
- Location of target cells: Testes and Ovaries
- Hormone function: Stimulates secretion of testosterone; triggers ovulation and stimulates secretion of estrogen and progestrogen
What gland is Prolactin (PRL) secreted from, what is the location of target cells, and what are the hormone functions?
- PRL is secreted by the anterior pituitary gland
- Location of target cells: Mammary gland
- Hormone function: Stimulates production and secretion of milk
What gland is Adrenocorticotropic Hormone (ACTH) secreted from, what is the location of the target cells, and what are the hormone functions?
- ACTH is secreted by the anterior pituitary gland
- Location of target cells: Adrenal cortex
- Hormone function: Stimulates secretion of hormones by adrenal cortex
What gland is Melanocyte stimulating Hormone (MSH) secreted from, what is the location of the target cells, and what are the hormone functions?
- MSH is secreted by the anterior pituitary gland
- Location of target cells: Skin
- Hormone function: Darkens skin pigment
What gland is Antidiuretic Hormone (ADH) secreted from, what is the location of the target cells, and what are the hormone functions?
- ADH is secreted by the posterior pituitary gland
- Location of target cells: Kidneys
- Hormone function: Decreases water lost in urine by returning water to the blood
- You inhibit release when drinking, causing you to pee more
What gland is Oxytocin (OT) secreted from, what is the location of the target cells, and what are the hormone functions?
- OT is secreted by the posterior pituitary gland
- Location of target cells: Uterus and mammary glands
- Hormone function: Stimulates uterine contractions and milk ejection during suckling
- This is used in a postive feedback loop during labor
What gland is T3/T4 secreted from, what is the location of the target cells, and what are the hormone functions?
- T3/T4 is secreted by the thyroid gland
- Location of target cells: Most body cells
- Resides in Colloid (5)
- Hormone function: Increases metabolism and basal metabolic rate (BMR)
- Produced by Follicular cells
What gland is Calcitonin secreted from, what is the location of the target cells, and what are the hormone functions?
- Calcitonin is secreted by the thyroid gland
- Secreted by Parafollicular cells (4)
- Location of target cells: Osteoblast cells in bones
- Hormone function: Decreases blood calcium levels by increasing osteoblast activity
- Make sure you remember: Parathyroid Hormone (PTH) increases blood calcium
What gland is Parathyroid Hormone (PTH) secreted from, what is the location of the target cells, and what are the hormone functions?
- ***PTH release is stimulated by high calcium
- PTH is secreted by the parathyroid glands
- Secreyed by principle cells
- Location of target cells: Osteoclast cells in bones
- Hormone function: Increases blood calcium levels by stimulating osteoclasts to break down bone matrix
- This opposes calcitonin
Label the parts of the adrenal medulla
(4) Capsule
(5) Adrenal Cortex
(6) Adrenal medulla
Label the different divisions and zones of the tissue within the adrenal medulla. What do the different zones do?
What gland is aldosterone secreted from, what is the location of the target cells, and what are the hormone functions?
- Aldosterone is secreted by the adrenal cortex
- Location of target cells: Kidneys
- Hormone function: Decreases sodium and water loss in urine by returning sodium and water to the blood
What gland is cortisol secreted from, what is the location of the target cells, and what are the hormone functions?
- Cortisol is secreted by the adrenal cortex
- Location of target cells: Liver, muscle, and cells involved in body defenses
- Hormone function: Increases resistance to stress, increases blood glucose levels, and decreases inflammation
What gland is DHEA secreted from, what is the location of the target cells, and what are the hormone functions?
- DHEA is secreted by the adrenal cortex
- Location of target cells: Uterus, mammary glands, and other body cells involved in secondary sex characteristics
- Hormone function: Insignificant in males; increases sex drive in females
What gland is Epinephrine and norepinephrine secreted from, what is the location of the target cells, and what are the hormone functions?
- Epinephrine and norepinephrine is secreted by the adrenal medulla
- Location of target cells: Body cells involved in fight or flight response
- Hormone function: Promotes fight or flight response
Lable the pancreas image below
- Head
- Body
- Tail
What is special about pancreas hormones?
- Has both endocrine and exocrine function
- We’ll just talk about endocrine for now
- High blood sugar
- Activates release of insulin from Beta Cells, which causes more uptake of sugar by the body’s cells
- Low blood sugar
- Activates release of glucagon from Alpha cells, which causes release of sugar from glycogen storage in the liver
What do Alpha and beta cells do in the pancreas?
- Alpha cell increase the amount of glucose in cells by secreting glucagon
- Beta cells decrease the amount of glucose going into cells and increases the amount of glucose going out of cells by secreting insulin