Nephron & Endocrine Glands

Glomerolus

Filters blood to nephron

• big stuff stays in capillaries (protein & cells)
• small stuff leaves (water, glucose, urea!!)

Bowman's capsule

Collects nephric filtrate (filtered fluid) from the glomerulus

Proximal tubule

reabsorbs GOOD stuff

• glucose
• amino acids
• water

Loop of Henle

controls water & salt balance
Increases urine concentration

Distal tubule

"Fine-tunes" balance

• adjusts ions, pH

Collecting tubules

Controlled by hormones like ADH
URINE OUT OF KIDNEY TO URETER

Hypothalamus

Releases GnRH
Target: pituitary gland
Job: controls pituitary

anterior pituitary gland

GH, TSH, FSH, LH,

GH (growth hormone)

Target: is muscles, bones
Grows them
Non-tropic

Prolactin

Target: mammary glands
Job: Milk production
Non-tropic

TSH (thyroid stimulating hormone)

Stimulates thyroid gland to produce thyroid hormones T3 & T4,
Tropic

FSH (follicle stimulating hormone)

Stimulates secretion of ovarian sex hormones
Development of ovarian follicles, and sperm production
Tropic

ACTH (adrenocorticotropic hormone)

Stimulates adrenal cortex to release glucocorticoids (cortisol)

LH (luteinizing hormone)

Ovulation/testosterone release
Target: ovaries/testes
Tropic

Posterior pituitary

Contains ends of nerve cells coming from the hypothalamus
Oxytoxcin & ADH

Oxytocin

A hormone released by the posterior pituitary that stimulates uterine contractions during childbirth and milk ejection during breastfeeding

ADH (antidiuretic hormone)

Produced by Posterior lobe of Pituitary Gland.
Targets kidneys for water conservation

Thyroid gland

Hormones T3 & T4
Target: most body cells
Job: METABOLISM

Parathyroid

PTH (parathyroid hormone)
Target: bones & kidneys
Job: Increase blood calcium / controls Ca levels

PTH (parathyroid hormone)

Target: bones & kidneys
Job: Increase blood calcium / controls Ca levels

Pancreas

Insulin & glucagon
2

Insulin

Target: body cells
Job: LOWERS the level of sugar in the blood

Glucagon

Target: liver
Job: RAISES blood glucose/sugar levels

Diabetes mellitus

Type 1 or 2

• frequent urination
• increased thirst
• increased appetite

Type 1 diabetes mellitus

Insulin NOT produced
Diagnosed in childhood

Type 2 diabetes mellitus

Reduced insulin production
Damaged insulin receptor
Diagnosed as adults
Can be managed by lifestyle changes

Gestational diabetes

Pregnancy hormones effect insulin
Results in INSULIN RESISTANCE
Goes away after pregnancy !!

Diabetes insipidus

Pituitary gland produces insufficient ADH
Kidneys make a lot of urine

Normal: 1-3 L/day
A lot: 19+ L/day

Adrenal glands

Target: heart & muscles
Job: fight or flight
Outer and inner cortex

Adrenal cortex (outer)

Produces steroid hormones called CORTOIDS which are released when ACTH acts on these glands
Mineralcorticoids
Glucocorticoids
Androgen-like hormones

Mineralcordicoids

Aldosterone
Affects kidneys, regulating water, and ions
Balance to blood pressure

Glucocorticoids (cortisol)

Cortisol: long-term stress
Regulate blood-glucose-levels

Androgen-like Hormones

Causes development of masculine features

Adrenal Medulla (inner)

Secretions help the body deal with ?
Contains many nerves

• Epinephrine (Adrenalin)
• Norepinephrine (noradrenaline)

Epinephrine (adrenaline)

Release is triggered by stress OR
Fright, excitement, or pain
Prepares your whole body for action

• increased heart rate
• opens airways
• increases blood flow of muscle muscles.

noepinephrine (nonadrenaline)

Focusses on blood vessels and alertness

• constricts blood vessels
• increases blood pressure
• makes you more alert

Thymus gland

Hormone: thymosin
Targets: immune cells

Pineal gland

Hormone: Melatonin
Target: brain
Job: sleep cycle

Ovaries

estrogen and progesterone

Estrogen

Target: uterus & body
Female traits, our cycle

Progesterone

Target: uterus
Job: maintain pregnancy

Testes

testosterone

Testosterone

Target: Male body tissues
Job: make traits, sperm production

Gonadotropic Hormones (FSH and LH)

Production and secretion stimulated by the gonadotropic releasing hormone (GnRH)
Target the testes to regulate sex-related functions
Releases by HYPOTHALAMUS in puberty

Female Hormones

Diploid primary oocyte in the ovary develops into a haploid ovum
Each oocyte is surrounded by a follicle containing granular cells that help develop

Ovarian cycle

Flow phase (menstruation)
Follicular phase (development of oocyte into ovum)
Luteal phase (ovulation & development of corpus luteum)

Developing follicles secretes…

Estrogen

Estrogen level, stimulates, thickening of…

Endometrium (uterus lining)

Increased progesterone increases thickening of…

?

Progesterone causes pituitary to…

If fertilization DOES NOT occur

Corpus Luteum breaks down
Progesterone no longer produced
Uterus contracts, endometrium breaks down
Pituitary no longer inhibited, so GnRH is released again

If fertilization DOES occur

Corpus luteum continues to produce progesterone
Uterine contractions inhibited
Endometrium maintained
Ovum implants into endometrium: Pregnancy!!

Menopause

Reduction in # of functioning follicles with age
Causes a DECREASE in amount of estrogen and progesterone
Menstrual cycle stops
Some other effects are:

• increased cholesterol levels
• increased risk of heart disease
• decreased bone mass
• mood changes
• alternating constricting and dilation of blood vessels (hot flashes)