Endocrine System Flashcards Preview

Anatomy and Phisiology > Endocrine System > Flashcards

Flashcards in Endocrine System Deck (41):
1

Hormones regulate

Growth (TH and GH)
Stress management (NE and cortisol)
Blood sugar levels (insulin and glucagon)
Reproduction cycles (testosterone)

2

Hypothalamus

Production of ADH, oxytocin, and regulatory hormones

3

Pineal gland

Melatonin

4

Parathyroid glands

Parathyroid hormone (PTH)

5

Thyroid gland

Thyroxine (T4)
Triiodothyronine (T3)
Calcitonin (CT)

6

Adrenal glands

Adrenal medulla
Epinephrine (E)
Norepinephrine (NE)


Adrenal cortex
Cortisol, corticosterone, aldosterone, androgens

7

Pancreas

Insulin
Glucagon

8

Because hormones are released into the bloodstream...

The effect of hormones are typically slow to appear

But effects last a longtime.

9

Amino acid derivatives

Tryptophan and tyrosine

10

Tryptophan

An amino acid that is used to make a hormone called melatonin

11

Tyrosine

An amino acid that makes thyroid hormones

12

Classes of hormones include

Amino acid derivatives
Lipid derivatives
Small peptides

13

Many hormones never actually enter the cell...

They bind to receptors which then trigger responses inside the cell

14

Steroid based hormones

Tend to diffuse across the plasma membrane before binding to receptors in the nucleus

15

What sits in the sella turcica of the sphenoid bone

The pituitary gland

16

Hormones released by the....

Posterior pituitary
-oxytocin
-antidiuretic hormone (ADH)

Anterior pituitary
Growth hormone (GH)
Thyroid stimulating hormone (TSH)
Adrenocorticotropic hormone (ACTH)
Follicle stimulating hormone (FSH)
Luteinizing hormone (LH)
Prolactin (PRL)

17

Supraoptic and paraventricular nucleus secretes...

Supraoptic: secretes ADH

Paraventricular: secretes oxytocin

18

When ADH is released by posterior pituitary

- diuretics= increases urine production

- ADH= decreases urine production and helps avoid dehydration

-hypothalamic neurons in the SON are osmoreceptors= they monitor the solute (osmotic) concentration of blood

-when the blood is too concentrated (high osmolarity) ADH is released

19

Osmoreceptors...

Baroreceptors...

Detect increased osmotic pressure

Detect decreased blood pressure

20

Because ADH is a vasoconstrictor...

ADH is also called vasopressin

21

Examples of things that inhibit the release of ADH

Caffeine
Alcohol

22

Diabetes insipidus

Most common form occurs when a blow to the head reduces ADH by posterior pituitary

- patient is constantly thirsty
-patient exhibits polyuria (pees a lot)

23

Functions of oxytocin

1) stimulates smooth muscle construction in the uterus during childbirth. A spike in oxytocin levels promotes delivery

2) oxytocin is part of the milk let-down reflex in nursing mothers

24

Portal system

A capillary bed feeds into veins which feed into another capillary bed

25

The thyroid gland contains 2 lobes connected by an

Isthmus

26

What synthesizes T3 and T4 and what stores T3 and T4

1) cuboidal epithelium of the follicle

2) colloid of the follicle

27

What affects nearly every cell of the body

T3 and T4

28

Thyroid hormones increase the metabolic rate of nearly every cell in the body by...

1) binding to receptors in the mitochondria thus increasing rates of ATP production

2) binding to receptors in the nucleus thus increasing the production of enzymes of glycolysis, Krebs and ETC

29

Thyroid hormones also

1) increase the force of heart contraction which results in increased blood pressure

2) in growing children, thyroid hormone is also essential in the development of skeletal, muscular and nervous systems

30

Hypothyroidism symptoms (adults)

Aka myxedema
-dry skin
- feeling chilled
-constipation
-mental sluggishness
-lethargy
-weight gain

31

Hypothyroidism can result from..

1) Low iodine levels
2) low thyroid gland function
3) low blood levels of TSH or TRH

Some cases it may result in a goiter

32

Hypothyroidism (in infants)

Aka cretinism
Symptoms:
Thick tongue and neck
Short stature
Mental retardation

Causes:
1) genetic deficiency
2) lack of iodine during pregnancy

33

Hyperthyroidism

Aka Graves’ disease

Symptoms:
1) weight loss
2) expothalmos (bulging eyes)
3) anxiety
4) heat intolerance

34

Thyroid gland also contains C cells aka

Parafollicular cells

35

What hormone do c cells produce

Calcitonin which is released in response to high blood calcium levels

36

Calcitonin lowers blood calcium levels in three ways

1) promote the entry of calcium into bone

2) increasing the rate of calcium excretion by the kidneys

3) decreasing the absorption rate of calcium by intestines

37

Parathyroid glands

Release PTH in response to low blood calcium levels

38

PTH raises blood calcium levels by

1) stimulating calcium release from bone

2) increasing calcium reabsorption by kidneys (it stops calcium loss in urine)

3) increases calcium absorption by the intestines

4) stimulates the release of calcitriol by kidneys

39

Calcitriol main function is

To enhance calcium absorption by intestines

40

The thyroid gland and the 4 parathyroid glands are very...

Vascular

41

The parathyroid glands respond to circulating blood and release PTH when....

Blood calcium levels are too low