pupil

Controls the amount of light that enters the eye.

Iris

The pigmented muscular structure surrounding your pupil that regulates pupil size.

sclera

The white portion of the eye, which has an outer covering called the conjunctiva.

cornea

The transparent covering of the pupil and iris.

conjunctivitis

It is the inflammation of the conjunctiva, often called pinkeye when infectious.

lacriminal gland

 The gland that produces tears (a dilute salt solution). Lacrimal glands continually release this dilute salt solution to lubricate the eye.

Hypothalamus

• Definition: A brain region that connects the nervous and endocrine systems.

• Function: Controls the pituitary gland by sending releasing or inhibiting hormones.

• Simple role: “The boss that tells the pituitary what to do.”

Pituitary gland

• Definition: Small pea-sized gland hanging under the hypothalamus.

• Nickname: “Master Gland” because it controls many other glands.

• Has 2 lobes: Posterior & Anterior.

Posterior pituitary

• Tissue Type: Nervous tissue

Role: Stores and releases hormones made by the hypothalamus

Oxytocin

• Meaning: “Childbirth & bonding hormone”

Function: Causes uterine contractions during labor and milk ejection in breastfeeding.

ADH/ Antideuretic hormone

• Meaning: “Water-saving hormone”

Function: Helps kidneys reabsorb water → reduces urine. Also slightly increases blood pressure.

Diabetes insipidus

• Cause: Not enough ADH

• Signs: Excessive urination + constant thirst

Anterior pituitary

• Tissue Type: Glandular tissue

• Role: Makes and releases its own hormones

• Controlled by: Hypothalamus through blood vessels (portal circulation)

growth hormone

Stimulates growth & breaks down fat for energy

hyposecretion of GH in childhood

dwarfism

hypersecretion of GH in adult

gigantism

Acromegaly

abnormal enlargement of body parts (especially hands, feet, face) due to excess growth hormone in adults.

prolactin

Maintains milk production after childbirth

tropic hormones

Tell other glands to release hormones

sterility

lack of tropic hormones

FSH & LH

Control egg, sperm, and sex hormone production

TH/ THYROID HORMONE

Stimulates thyroid hormone release

ACTH/ ADRENOCORTICOTROPIC HORMONES

Stimulates adrenal cortex to release stress hormones

PINEAL GLAND

• Location: Roof of the third ventricle inside the brain

MELATONIN

Hormones release by pineal gland

pineal gland

• Function: Controls sleep-wake cycle; levels rise at night (makes you sleepy)

• Extra role: Helps time puberty and fertility

THYROID GLAND

• Location: Base of the throat; has 2 lobes connected by an isthmus

• Stores hormones in: Follicles

T3 is known as

thyronine

t3, t4, & calcitonin

Hormones released by thyroid gland

Thyroid hormone (T3 & T4)

• Body’s main metabolic hormone

• Function: Controls energy use (ATP), heat production, and normal growth (especially brain & reproductive organs)

• Needs iodine to work

Calcitonin

Lowers blood calcium by storing it in bones

Cretinism (children)

• Too little thyroid hormone

  • Stunted growth + low intellect

Myxedema (adults)

• Too little thyroid hormone

• Sluggish, cold, low metabolism/temperature

Graves disease

• Too much Th

• Fast heartbeat, weight loss, heat intolerance, bulging eyes (exophthalmos)

Parathyroid Gland

• Location: Four tiny glands behind the thyroid

Parathyroid hormones

Hormones released by parathyroid gland

Parathyroid Hormone

• Function: Raises blood calcium by:

  • Breaking down bone (releases Ca²⁺)

  • Increasing Ca²⁺ absorption in kidneys & intestines

Parathyroid Hormones

Opposes (antagonistic to) Calcitonin

Tetany 

• Too little PTH → neurons overfire → painful muscle spasms

• neurons become irritable, leading to muscle spasms.

Thymus 

• Location: Upper chest; large in children, shrinks in adults

Thymosin

hormone released by thymus gland

Adrenal Glands

• Location: Sit on top of kidneys

thymosin

Function: Helps T cells (immune cells) mature → strong immune defense

Adrenal Gland

• Has 2 regions: Cortex (outer) & Medulla (inner)

cortex & medulla

2 regions of adrenal gland

outer layer

adrenal cortex is in the

inner layer

adrenal medulla is on the

Zona glomerulosa

Layer of mineralocorticoids

Zona fasciculata

layer of glucocorticoids

Zona reticularis

layer of androgen or sex hormones

Aldosterone

• Example of mineralocorticoids

• Controls salt & water balance (Na⁺ ↑, K⁺ ↓)

Cortisol/cortisone

• Example of glucocorticoids

• Long-term stress → raises blood sugar, reduces inflammation, weakens immune response

Estrogen, Progesterone, Testosterone

Support male/female traits or characteristics

Epinephrine & noripeniphrine

hormones released by adrenal medulla

Epinephrine & noripeniphrine

• Activates fight or flight response

  • Raises heart rate, blood pressure, blood glucose

  • Widens air passages to increase breathing

Pancreatic gland

• Location: Scattered endocrine cells within the pancreas

• Nicknamed: “Fuel sensor of the body”

Insulin & Glucagon

Hormones released by pancreatic gland

beta cells

cells in insulin

alpha cells

cells in glucagon

insulin

• High blood sugar

• Lowers blood glucose by helping cells absorb/store it

Insulin

• Triggers high blood sugar

• Lowers blood glucose by helping cells absorb/store it

Glucagon

• Triggers low blood sugar

• Raises blood glucose by releasing stored sugar

Diabetes mellitus

• Not enough insulin or cells don’t respond to insulin

Effects: High blood sugar, sugar in urine, fat breakdown → acidic blood

Polyurina

excessive urination

polydipsia

excessive thirst

polyphagia

excessive hunger/appetite

Gonads

sex glands

Ovaries & Testes

Hormones released by gonads

ESTROGEN & PROGESTERONE

Hormones released by the ovaries

Estrogen

Female traits + prepares uterus + menstrual cycle

Progesterone

Maintains pregnancy + works with estrogen in cycle

Testosterone

hormones produced by testes

Testes

• Male traits + sperm production

55%

plasma percent

44%

red blood cells percent

1%

white blood & platelets percent

plasma

• makes up 55% of blood; 90% of water

• Contains 100+ dissolved substances:

  • Nutrients

  • Salts (electrolytes)

  • Gases

  • Hormones

  • Wastes

plasma proteins

mainly from liver

Albumin

• Carrier molecule

• Maintains osmotic pressure (keeps water in bloodstream)

• Acts as a buffer

Clotting proteins

• prevent blood loss

platelets

stop the bleeding

antibodies

defend against pathogens

Erythrocytes, leukocytes, platelets

the three formed elements

45%

percent of the formed elements

Erythrocytes

Transport oxygen and help transport carbon dioxide

Leukocytes

defense and immunity

platelets

blood clotting

anemia

• Low oxygen-carrying capacity
  NOT low blood pressure, but can CAUSE low B

Iron-deficiency anemia

• Low iron → pale palpebral conjunctiva

hemorrhagic

blood loss

hemolytic

rcbs rupture

pernicious

Low vitaminB12

Aplastic

bone marrow failure

sickle cell anemia

abnormal hemoglobin

Pallor, Dizziness, Fatigue

Signs of anemic

polycythemia

• Too many RBCs

• Causes: bone marrow cancer, high altitude

• Effects: blood becomes thick → circulation slows

polycythemia

• Signs: red tongue, palms, eyes

• what rbc disorder?

Diapedisis

squeeze in/out of blood vessels

amoeboid movement

crawling movement

positive chemotaxis

• follow chemical signals to infection

leukocytosis

a wbc disorder that has high wbc