LAB quiz #4 Flashcards
Contents of Endocrine system?
Pituitary gland, pineal gland, testicle, adrenal gland, thymus, thyroid, pancreas, and ovary.
Function of Endocrine System?
- functions in integration of body cells by working with the nervous system
- second major control system of the body
- maintenance of homeostasis
Glands
a group of cells or an organ that produces a secretion for use in the body or surrounding
Hormones
long-distance chemical messengers that travel through either the blood or lymph
Target cells
cells within an organ that respond to a
particular hormone
2 classes of hormones
- amino acid based
- steroid
Hypothalamus
- the major controller of endocrine glands
- coordinates the autonomic nervous system and anterior pituitary
- controls homeostatic systems ( temp., thirst, hunger, etc.)
- involved in sleep and emotion control
Pituitary gland
aka hypophysis
Anterior Pituitary
- Secretes a number of hormones
- Controls the activity of many other endocrine glands
- Sometimes called the mater endocrine glands
Posterior Pituitary
- not technically an endocrine gland because it does
not synthesize its own hormones - Acts as a storage unit for 2 neurohormones
Endocrine Glands
- pineal
- thyroid
- parathyroid
- thymus
- adrenal gland
- pancreas
- the gonads(ovaries & testes)
Pineal Gland
- Peaks at night making us drowsy
- Lowest at noon
Thyroid Gland
- regulates growth and development via metabolic rate
Parathyroid Gland
- regulates body’s calcium levels
Thymus
- Involved in the development of T lymphocytes and
the immune response - Begins to atrophy at puberty & is inconspicuous by
old age
Adrenal Glands
- Release a hormone mix of epinephrine and
norepinephrine - The hormones released act with the sympathetic
nervous to produce the fight or flight response
Pancreas
- Functions as an endocrine gland and an
exocrine gland - Produces digestive enzymes
- Also produces insulin and glucagon involved in
blood sugar level regulation
The Gonads
The endocrine and exocrine functions of the gonads begin at the onset of puberty
Ovaries
- Female gonads
- Produces the steroid hormones estrogen and
progesterone - These hormones promote the development of the female
reproductive organs, secondary sex characteristics, and
regulate the menstrual cycle
Testes
- Male gonads
- Produce testosterone
- This hormone promotes the development of the male
reproductive organs, secondary sex characteristics, sperm production, and sex drive
Endocrine Disorders
Result from either hyposecretion or hypersecretion of a specific hormone
growth hormone disorder
hyposecretion: pituitary dwarfism
hypopersecretiton: gigantism, acromegaly
Antidiuretic hormone(ADH) disorder
Hyposecretion: diabetes insipidus
hypersecretion: Syndrome of
inappropriate ADH
secretion
Insulin disorder
hyposecretion: diabetes mellitus
hypersecretion: hypoglycemia
The digestive system
- Provides body with essential nutrients,
water, and electrolytes - Digestive organs function to ingest,
digest, and absorb food and also
eliminate the undigested foo
Digestion
- the breakdown of ingested food into smaller, diffusible molecules
Absorption
- when digested food molecules pass through epithelial cells lining the tract into the blood for distribution to the body’s cell
Gastrointestinal (GI) Tract
- mouth
- pharynx
- esophagus
- stomach
- small intestine
- large intestine
Accessory Organs
- pancreas
- liver
- gallbladder
- teeth
- salivary glands
Mouth
food enters the digestive tract through the oral cavity( mouth)
- contains the tongue, teeth, openings of the salivary gland ducts, and more
- lips and cheeks help hold food between the teeth during chewing
- tongue manipulates food during chewing and initiates swallowing
Pharynx
the pharynx is common passageway or food, fluid, and air
Divided into 3 parts:
- Nasopharynx: behind the nasal cavity
- Oropharynx: behind the oral cavity
(mouth)
- Laryngopharynx: behind the larynx
- Food enters the oropharynx through the
oral cavity after mastication (chewing)
- This initiates a wave-like motion to push
food downwards
Esophagus
- extends from the laryngopharynx
through the diaphragm to the
gastroesophageal sphincter
(controls food passage in the the
stomach) - Has no digestive or absorptive
function - Simply pushes food down to
gastroesophageal sphincter at top
of stomach via peristalsis
Stomach
- Third oblique layer of smooth muscle
allows churning of food to break down to
smaller pieces - Gastric glands secrete HCl
- Mucosal glands secrete mucus to protect
stomach from proteolytic enzymes - Both physical and chemical breakdown
occur here - Most digestion occurs in pyloric part of
stomach - Chyme – creamy mass of broken down
food that enters the small intestine
Small intestine
-Stomach -> Duodenum -> Jejunum ->
Ileum
- Runs from pyloric sphincter of stomach
to ileocecal valve at large intestine
- Enzymes from 2 sources complete
digestion: brush border enzymes and
pancreatic enzymes
- Nearly all nutrient absorption occurs
here (microvilli, villi, and circular folds
increase absorption)
Large Intestine
Divided into 5 parts:
- Cecum
- Appendix (can be a problem area)
- Colon
- Rectum
- Anal canal
Propels unusable feces and bacteria
towards anus for elimination from body
- Provides a site where bacteria
make vitamins B and K
- Reclaims most of the water left in
the feces to conserve
Teeth
◦ Deciduous teeth – initial set of teeth
◦ Permanent teeth – second set that
gradually replaces the first set
◦ Functions in breaking down food
◦ Incisors exert a shearing action during
biting
◦ Canines are used for tearing food
◦ Premolars and molars are used for fine
grinding of food
Salivary Glands
Three pairs of salivary glands empty secretions into the mouth:
◦ Parotid glands: located anterior to the ear and ducts into the mouth over the second upper molar to the parotid duct (mainly serous)
◦ Submandibular glands: located on the medial mandibular body in the floor of the mouth and ducts under the tongue to the linguinal frenulum (mixed)
◦ Sublinguinal glands: located in the front of the floor of the mouth and empties under the tongue through multiple ducts (mainly mucin)
- Food in the mouth stimulates salivary glands to secrete
saliva
- Saliva contains mucin (moistens and binds food) and
salivary amylase (begins digestion of starch
Liver
Largest gland in the body, located below the diaphragm
- very important in processing the nutrient-rich blood draining the digestive organs
- produces bile
- bile leaves the liver through the common hepatic duct and enters the duodenum through the bile duct
Gallbladder
A small, green sac on the inferior surface of the liver
- bile enters the gallbladder when digestive activity stops
Pancreas
A triangular shaped gland that extends horizontally from the spleen to the duodenum
◦ Endocrine function: producing
insulin and glucagon
◦ Exocrine function: secreting
enzymes into the duodenum
through the pancreatic ducts
