Chapter 17 - Endocrine System Flashcards
(38 cards)
What is the definition of a target cell?
A cell whose activity is affected by a particular hormone. Hormones chemically bind to specific protein receptors on target cells.
what tissues are the endocrine glands composed of?
epithelial tissue
What is the key characteristic of target cells for a given hormone?
Only target cells for a given hormone have receptors that bind and recognize that hormone.
What are the two main categories of hormones based on solubility?
Water-soluble and Lipid-soluble hormones.
What is the mechanism of action of water-soluble hormones inside the cell?
They use second messengers to activate various proteins inside the cell.
What is the mechanism of action of lipid-soluble hormones inside the cell?
They affect gene expression.
What are the two main functional classes of chemical messengers in the endocrine system?
Hormones and neurotransmitters.
what types of Control of Hormone Release?
- humoral
- neural
- hormonal
what is the humoral hormone release cause?
- Capillary blood contains low concentration of Ca2+
- then stimulating the parathyroid glands
- then secreting PTH
what is the neural hormone release cause?
- the preganglionic SNS stimulates adrenal medulla cells
- then secreting catecholamines
what does the parathyroid gland secrete?
Parathyroid hormone (PTH) increases blood Ca++ levels
what is the effect of the hormonal release in the hypothalamus?
- the hypothalamus secretes hormones
- then stimulates the anterior pituitary gland to secrete hormones
- which then stimulate other endocrine glands (thyroid gland, adrenal cortex and gonad-testis) to secrete other hormones
Label the endocrine system
What are the names of the two types of glands in the Hypothalamus-Pituitary system?
Adenohypophysis (granular tissue) and Neurohypophysis (neural tissue)
what hormones are secreted by the adenohypophysis?
Secrete primarily tropic hormones
* Regulate secretion of other hormones
* Stimulatory or inhibitory hormones
- Hypothalamus: tropic hormone #1
- Anterior pituitary: tropic hormone #2
- Endocrine gland: hormone #3 which acts on target
what is the difference between long negative feedback loop vs short loop negative feedback
tropic effect
what hormones are involved in the Hypothalamo–Pituitary-target organ relationship
- Prolactin (PRL)
- TSH
- LH
- FSH
- GH
- ACTH
what type of Control of Pituitary Secretion?
tropic effect
What hormones are secreted by the neurohypophysis?
Antidiuretic hormone (ADH) and Oxytocin.
what does the thyroid gland secrete?
- T3 and T4 (thyroid hormones) regulate metabolism, growth, and development
- Calcitonin decreases blood Ca++ levels
Label the structures of the thyroid and parathyroid glands
Which hormones regulate blood calcium levels?
Parathyroid hormone (PTH) increases blood Ca++ levels, while Calcitonin decreases blood Ca++ levels.
what are structural and functional divisions of the adrenal glands?
- Cortex
Outer 3 layers
80% of total mass - Medulla
Central tissue
20% of total mass
Label the structure of the Adrenal gland and adrenal cortex