Transcript Organs and Organ Systems

ORGANS AND ORGAN SYSTEMS
Are you organized?
organization
 Life is characterized by hierarchical levels of
organization.
 Animals are multicellular organisms with their
specialized cells grouped into tissues.
 Combinations of various tissues make up
functional units called organs
 Groups of organs that work together form organ
systems.
 Cell
Tissues Organ
Organ system
ORGANIZATION
organs
 In all but the simplest animals (sponges and
some cnidarians) different tissues are
organized into organs
 These organs also organized to form a group
working together called ORGAN SYSTEMS.
ORGAN SYSTEMS
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Digestive
Respiratory
Integumentary
Immune
Lymphatic
Muscular
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Skeletal
Nervous
Endocrine
Excretory
Reproductive
Circulatory
Organ systems
 Each organ system consists of several organs
and has specific functions
Organ system
Main components
Main Function
Digestive
Mouth,pharynx,
esophagus,stomach,
intestines,liver, pancreas,
anus
Food processing (
mastication, ingestion,
digestion, absorption,
elimination
Circulatory
Heart, blood vessels,
blood
Internal distribution of
materials
Respiratory
Lungs, trachea, alveolus
Gas exchange (uptake of
O2, disposal of carbon
dioxide
Organ system
Main Component
Main Function
Immune and Lymphatic
Bone marrow, lymph
Body defense
nodes, thymus, spleen,
lymph vessels, white blood
cells
Excretory
Kidneys, ureters, urinary
bladder, urethra
Disposal of metabolic
wastes, regulation of
osmotic balance of blood
Endocrine
Pituitary, thyroid,
pancreas, other hormone
secreting glands
Coordination of body
activities (digestion,
metabolism)
Reproductive
Ovary, testes, other
associated organs
Reproduction
Organ system
Main Component
Main Function
Nervous
Brain, spinal chord, nerves, Coordination of body
sensory organs
activities, detection of
stimuli and formulation of
response to them
Integumentary
Skin and its derivatives
Protection against
mechanical injury,
infection, drying out
Skeletal
Skeleton ( bones,
cartilage, tendons,
ligaments)
Body support, protection
of internal organs
Muscular
Skeletal muscles
Movement, locomotion
Digestive system
 Digestion-The breakdown of large molecules
(food) into small soluble molecules.
 This is done by digestive juices and
enzymes.
 Once food is digested it can pass through
your gut wall into your blood.
 Your blood then carries the digested food all
around your body where it is used for growth,
movement and repairing cells.
 Digestion begins in your mouth with action of
your teeth and tongue (mechanical digestion)
and your salivary glands (chemical digestion)
(MASTICATION).
 The salivary glands produce enzymes
(PTYALIN,AMYLASE) that are mixed with the
food, breaking down the starches.
 PERISTALSIS is the muscular action that moves
the food through the esophagus and into your
stomach after you swallow
STOMACH
stomach
 The food (through
peristaltic movement)
moves into your stomach,
which contains chemicals
such as hydrochloric acid
and pepsin.
FUNCTIONS:
1. Storage and mixing of food bolus from the
esophagus
2. Secrete substances that start digestion of
protein (enzymes, mucus, and HCl)
3. Help control the rate at which food moves
into the small intestine via the pyloric
sphincter.
 Distention of stomach as food bolus enters
 Pepsin breaks proteins, and other enzymes (HCl)
break down fat
 Salts and simple sugars can be absorbed rapidly
 3-4 hours after a meal, stomach contents have
been sufficiently mixed and are a semiliquid mass
(CHYME)
 Your stomach gradually releases these
materials into the upper small intestine
(duodenum), where digestion is completed.
 Your stomach also has a thick coating of
mucus to protect it form the acids and to keep
it from digesting itself!
 Empty stomach- peristaltic waves stop.
 10 hours of fasting- new waves occur (
HUNGER PANGS)
LIVER
 largest and heaviest organ of your body
 breaks down many substances and toxins,
 and produces bile- a substance that helps
break down fat.
 The bile flows from the liver into the gall
bladder, where it is stored until needed.
 The pancreas lies between the stomach and
the duodenum and produces enzymes that
flow into the small intestines, helping to break
up complex starches, proteins, and fats.
FUNCTIONS
 Conversion of carbohydrates
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and proteins into fat
Detoxification
Heat producer ( raising
temperature of blood passing
through it)
Manufacture bile salts
Main storage center
SMALL INTESTINE
 CHYME passes
through an opening (called the
pylorus sphincter)into the small intestines.
 all the nutrients are absorbed leaving
undigestible wastes.
 These wastes pass into the large
intestines, where water is removed.
 Then the wastes are
stored in the rectum until they are released by
the anus.
 The Villi add surface
area to increase
absorption of food and
nutrients. On the left
you see how the villi
line your small
intestines, and on the
left you see 1 villi with
its capillaries.
trivia
• The human large intestine, or colon, is
home to many microorganisms, such as
the bacterium Escherischia coli (E. coli).
• Certain foods contain large amounts of
carbohydrates that our digestive enzymes
cannot break down.
 When these carbohydrates reach the large
intestine, our gut microbes respond by
"having a party³ (reproducing rapidly,
giving off gases such as methane and
hydrogen sulfide as natural by-products of
their activities).
 This is the cause of the discomfort and
flatulence associated with eating beans,
cabbage, and other gas-promoting foods.
 Fortunately for gas sufferers, the enzymes
that enable our microbes to break down
complex carbohydrates are now available
in pill form.
 If these are taken before a meal, the
enzymes break down the carbohydrates in
the small intestine so that they can be
absorbed by the body before they reach
the hungry throngs of bacteria living in the
colon.
RESPIRATORY SYSTEM
 NASAL OR ORAL CAVITIES
 PHARYNX-common area for respiratory and
digestive tract
 Larynx- connected with the pharynx
 Epiglottis- flap, prevents food from entering
trachea when swallowing
INHALATION
 Air from the larynx moves into the trachea
(windpipe)
 Branches into right and left bronchioles
 Then to terminal bronchioles
 Respiratory bronchioles that connect to the
gas exchange portion of respiratory system
Gas exchange
 Surrounding alveoli are many capillaries
 Alveoli- functional unit of the lungs (gas
exchange portion)
 It is here that oxygen moves into the blood
and carbon dioxide moves from the blood to
the alveoli
Pulmonary ventilation
(breathing)
2 PHASES
1. INHALATION-intake of air
2. EXHALATION-outflow of air
inhalation
 Several sets of muscles contract (diaphragm
and intercostal muscles)- ENLARGEMENT OF
THORACIC CAVITY
 Thoracic cavity is enlarged further when the
diaphragms contracts and flattens
 The increase size of the thoracic cavity causes
the pressure in the cavity to drop below
atmospheric pressure, allowing air to rush
into the lungs, and they inflate.
exhalation
 The intercostal muscles and the diaphragm
relaxes- smaller thoracic cavity
 Abdominal muscles contract pushing the
abdominal organs against the diaphragm,
increasing pressure on thoracic cavity
 Contraction of lungs and compression of air
in alveoli-great alveolar pressure ( greater
than atmospheric pressure)-expulsion of air
alveoli