63 - Hormones, Synthesis, Regulation of Hormone Secretion, & Hormone Receptors

nervous system

What system does the endocrine system work in concert with to maintain homeostasis?

endocrine system

What is responsible for regulating growth, development, reproduction, blood pressure, ion concentration, behavior, and aging?

glands

Where are most hormones synthesized and secreted?

GIT

Hormones associated with what system are secreted by clusters of endocrine cells, with some made in the hypothalamus, placenta, and kidneys?

into the blood

Where do endocrine cells and neurons secrete substances?

yes

Is it possible for some molecules to be both neurotransmitters AND hormones?

a specific receptor

What does the mechanism of action for hormones and neurotransmitters require?

1. exocytosis of granules

2. synaptic vesicles

What are 2 similar processes associated with endocrine cells and neurons?

yes

Can endocrine cells and neurons respond to the same stimuli?

nervous system

The following characteristics are associated with which system?

-Mode: electrical ->chemical

-Messengers: neurotransmitters

-Release: close to cell of influence

-Target Cells: specific location (only at nerve supply)

-Speed: fast

-Duration: short

endocrine system

The following characteristics are associated with which system?

-Mode: blood borne

-Messengers: hormones

-Release: distance to cell of influence

-Target Cells: more widespread location

-Speed: slow

-Duration: long

Ability of body to maintain a stable internal environment despite changes in external conditions

What is the definition of homeostasis?

constantly

How often does dynamic equilibrium occur?

1. receptor

2. control center

3. effector

What are the 3 mechanisms that restore and maintain homeostasis?

negative feedback loops

What kind of feedback mechanism is associated with the maintenance of homeostasis?

no

Does positive feedback result in homeostasis?

it amplifies change in variable

Positive feedback does not result in homeostasis. Why?

1. nutrition

2. toxins

3. physiological

4. physical

5. genetic

6. medical

What are the 6 pathways that alter homeostasis?

1. endocrine/telecrine

2. neurocrine

3. autocrine

4. paracrine

What are the 4 hormone signaling pathways?

reviewed

Review

1. peptides & proteins

2. steroids

3. amines

4. eicosanoids

What are the 4 classifications of hormones?

amino acids

Where are peptide/protein hormones derived from?

1. insulin

2. growth factors

3. growth hormone

4. parathyroid hormone

5. thyroid-stimulating hormone

6. antidiuretic hormone

What are the 6 peptide/protein hormones?

similar hormones to act on multiple receptors

The structure of different peptide hormones may be similar to each other and may only differ by a side chain. What does this allow?

1. mRNA is transcribed and travels to cytoplasm

2. Message is translated on ribosome

3. Product is preprohormone - now transferred to ER

4. Signal peptide degraded in ER -results in prohormone, now transferred to Golgi

What are the steps of peptide and protein hormone synthesis?

cytoplasm

In peptide/protein hormone synthesis, where does mRNA travel after being transcribed?

preprohormone -> ER

In peptide/protein hormone synthesis, after the message is translated on the ribosome, what product do we get and where does it get transferred?

prohormone -> golgi

In peptide/protein hormone synthesis, after the signal peptide is degraded in the ER, what product to we get and where does it get transferred?

granule contents

What is released after an endocrine cell is stimulated?

tyrosine

Catecholamines are synthesized using what?

1. tyrosine

2. iodide

Thyroid hormones are synthesized from what (2)?

thyroglobulin

Thyroid hormones are stored in a follicle as what?

cholesterol

Steroid hormones are synthesized from what?

arachidonic acid

Prostaglandins are synthesized from what?

enzymatic

Catecholamines, thyroid hormones, steroid hormones, and prostaglandins use a series of what kind of reactions?

simple transfer

How do catecholamines, thyroid hormones, steroid hormones, and prostaglandins get transferred through the plasma membrane?

neural mechnaisms

What mechanisms for regulation of hormone secretion are less common?

neural mechanisms

The stimulation of preganglionic nerve causes release of catecholamine from the adrenal medulla is an example of what mechanism of regulation of hormone secretion?

feedback mechanisms

What mechanisms for regulation hormone secretion are more common?

1. long

2. short

3. ultra short

What are the 3 kinds of feedback loops do feedback mechanisms of regulation of hormone secretion use?

further secretion

When hormone levels are judged to be adequate or high by the negative feedback mechanism, what is inhibited?

when hormone/substrate levels are judged to be inadequate or low

When is secretion of a hormone stimulated, in relation to the negative feedback mechanism?

positive feedback

What kind of feedback mechanism is uncommon?

positive feedback

What is a feature of hormones action that causes more secretion of the hormone?

more estrogen

When estrogen from ovary stimulates follicle-stimulating hormone (FSH) and luteinizing hormone (LH) release from anterior pituitary, FSH and LH cause release of what?

dilation of the cervix

With dilation of the cervix, there is a release of oxytocin from posterior pituitary, causing uterine contractions. This causes more of what?