Transcript Day 18 Internal Organ Anatomy

Basic Anatomy
Gary Davis MD
Anatomical and Physiological Systems
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Cardiovascular
Skeletal
Nervous
Lymphatic
Respiratory
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Digestive
Urinary
Endocrine
Reproductive
Integumentary
system
Cardiovascular
System
• Transport
Skeletal System
• Protection
• Movement
Lymphatic
system
• Protection
Integumentary System
• Skin
• Protection
• Body Temp Control
• Sensory
• Excretion
Muscular
System
• Movement
Nervous System
• Sensory
• Integration
• Control
Central Nervous System
• Brain and Spinal Cord
Pg 361
Spinal Cord
• Passes inferiorly through foramen
magnum into vertebral canal
• 31 pairs of spinal nerves branch off
spinal cord through intervertebral
foramen
• Spinal cord made of a core of gray
matter surrounded by white matter
Pg 393
Organization of Nervous System
• Central Nervous System (CNS) = brain and spinal cord
• Peripheral Nervous System (PNS) = nerves
CNS
PNS
Spinal Nerves (31 pairs)
• Each pair of nerves located in particular segment
(cervical, thoracic, lumbar, etc.)
• Each nerve pair is numbered for the vertebra sitting
above it (i.e. nerves exit below vertebrae)
– 8 pairs of cervical spinal nerves; *C1-C8
– 12 pairs of thoracic spinal nerves; T1-T12
– 5 pairs of lumbar spinal nerves; L1-L5
– 5 pairs of sacral spinal nerves; S1-S5
– 1 pair of coccygeal spinal nerves; C0
Spinal Cord
Segments
Pg 393
Respiratory System
• Gas Exchange
The Respiratory System
Pharynx
Larynx
Trache
aLungs
Bronchus
Nose
Mouth
Epiglottis
Bronchioles
Diaphragm
Copyright Pearson Prentice Hall
Digestive
System
• Process food
• Nutrient absorption
General Structure and Functions
of the Digestive System
• The GI tract organs:
– Oral cavity
– Pharynx
– Esophagus
– Stomach
– Small intestine
– Large intestine
General Structure and Functions
of the Digestive System
• Form a continuous tube that extends about 30 feet (9–10
meters) from the mouth to the anus
• Smooth muscle in the GI tract wall pushes materials
from one end to the other
• Accessory digestive organs: do not form the long GI tube,
but often develop as outgrowths from and are connected
to the GI tract
• Assist the GI tract in the digestion of food
Supporting Elements for the Digestive
System
• Sphincter-a circular muscle
that constricts a passage or
closes a natural orifice
(opening)
• Cardiac sphincter
• Pyloric sphincter
• Food sits in stomach for 14 hours
• Gastric juices contain
hydrochloric acid- activates
pepsin, kills bacteria
Small Intestine
• Finishes the chemical digestion process and is responsible
for absorbing most of the nutrients
• Ingested nutrients spend at least 12 hours in the small
intestine as chemical digestion and absorption are
completed
• Coiled, thin-walled tube about 6 meters (20 feet) in length
• Extends from the pylorus of the stomach to the cecum of
the large intestine, and thus occupies a significant portion
of the abdominal cavity
Digestive Organ’s Functions cont.
Small Intestine
It has three parts, duodenum, jejunum and
ileum
Duodenum
Is responsible cor continuing to break down
of food
Jejunum
Absorbing nutrients into the blood stream
Iluem
Absorbing nutrients into the blood stream
Small Intestine
• The duodenum forms the first segment of the small
intestine
• Approximately 25 centimeters (10 inches) long and
originates at the pyloric sphincter
• The jejunum is the middle region of the small
intestine
• Extending approximately 2.5 meters (7.5 feet), it
makes up approximately two-fifths of the small
intestine’s total length
Small Intestine
• Primary region for chemical digestion and nutrient
absorption
• The ileum is the last region of the small intestine
• At about 3.6 meters (10.8 feet) in length, the ileum
forms approximately three-fifths of the small
intestine
• Its distal end terminates at the ileocecal valve, a
sphincter that controls the entry of materials into the
large intestine
Digestive Organ’s Functions cont.
Large Intestine
Also known as the colon
It has three major parts, ascending
colon, transverse colon and descending
colon
Rectum
Part of the colon, used to store waste for
disposal
Gall Bladder
Stores bile from the liver and releases
bile into the duodenum
Large Intestine
• Approximate length of 1.5 meters (5 feet) and a
diameter of 6.5 centimeters (2.5 inches)
• Absorbs most of the water and electrolytes from the
remaining digested material
• Watery material that first enters the large intestine
soon solidifies and becomes feces
Large Intestine
• Stores this fecal material until the body is ready to
defecate
• Absorbs a very small percentage of nutrients still
remaining in the digested material
• Composed of four segments:
– The cecum, colon, rectum, anal canal
Large intestine
• Separated from small intestine by ileocecal valve
• Final absorption of water, storage of indigestible
material, absorption of vitamins B and K by bacteria
• Colon connects to rectum-anal canal opens to the
anus (final opening)
– Fecal material is expelled
The Liver is where it all happens!!!!
• Liver- largest gland in
your body
• Secretes bile-emulsifies
fat, makes them water
soluble.
• Stores glucose in the
form of glycogen
• Makes clotting proteins
• Detoxifies blood
The Liver
• Produce bile: a greenish fluid that breaks down fats
into small droplets to assist in their chemical
digestion
• Detoxify drugs, metabolites, and poisons
• Store excess nutrients and vitamins and release them
when they are needed
The Liver
• Synthesize blood plasma proteins such as albumins,
globulins, and proteins required for blood clotting
• Phagocytize debris in the blood
• Help break down and recycle components of aged
erythrocytes and damaged or worn-out formed
elements
Accessory Organs:
and
Digestive Organ’s Gall
FunctionsBladder
cont.
Pancreas
Pancreas
The body’s sugar control board. Produces
insulin and glucagon
Liver
Food doesn’t pass through this organ, instead
the liver secretes bile
Gall Bladder
Stores bile from the liver and releases bile into
the duodenum
Appendix
We do not need our appendix, sometimes a
piece of food gets stuck in here and causes an
infection.
Pancreas
• Mixed gland because it exhibits both endocrine and exocrine
functions
• Endocrine functions are performed by the pancreatic islets
• Exocrine activity results in the secretion of digestive enzymes,
collectively called pancreatic juice, into the duodenum
• Secretes insulin, a hormone that transports glucose into cells
• Secretes glucagon- increases glucose in bloodstream
Gallbladder
• Concentrates bile produced by the liver and stores
this concentrate until it is needed for digestion
• Cystic duct connects the gallbladder to the common
bile duct
• Can hold approximately 40 to 60 milliliters of
concentrated
Endocrine System
• Hormones-chemical
messengers carried by
blood
• May stimulate other glands
– Regulate growth,
development,
metabolism, sex
processes
Major Glands of the Endocrine System
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Pituitary
Thyroid
Parathyroid
Adrenal
Pancreas
Ovaries
Testes
Pituitary gland
• Master gland of body
• Located in the depression of sphenoid bone
• Produces many hormones that affect other glands
– Thyroid stimulating hormone
– Somatotropin -- growth hormone
– Lutenizing (LH) -- causes ovulation
– ICSH -- causes testes to secrete testosterone
– Melanocyte stimulating -- distribution of melanin in skin
– ADH -- antidiuretic hormone
Pituitary Gland
Abnormalities
• Gigantism: oversecretion of
somatotropin before puberty
• Dwarfism: under secretion of
somatotropin
– Cause: tumor, injury, infection,
genetics
• Diabetes insipidus- decreased
ADH
Thyroid
• Produces hormones
that control metabolism
• Thyroid gland must
have source of iodine
• Goiter: not enough
iodine
• Hyperthyroidism
• hypothyroidism
Adrenal Glands
• Located just above the
kidney
• Secretes many
hormones
– Epinephrine
– Norepinephrine
• Many steroid hormones
– Estrogen
– Androgen
Reproductive System
• Necessary for offspring and continuation of the
species
• Endocrine and some exocrine function
• Supported by fascial attachments to the bony pelvis
Male Reproductive System
Female Reproductive System
Female Pelvic Organs
• Pelvic organs are protected by the bony pelvis and
are supported by the levator ani muscles and their
parietal fascia
Urinary System
• Maintains water and electrolyte balance
Bladder and Urethra
• A bladder is a pouch or other
flexible enclosure with
waterproof or gas-proof walls
• In the human female, the
urethra is about 1-1.5 inches
(2.5-4 cm) long and opens in
the vulva between the clitoris
and the vaginal opening
Summary
• All physiologic and anatomical systems are
interrelated
• Function determines structure
• Surgical procedures are often designed to restore
function and hopefully function