HUMAN BODY SYSTEMS

LEVELS OF ORGANIZATION:
Tissue
Organ
System
Cell Organ
A. CELLS - basic unit of life
Organism
B. TISSUE (groups of cells w/similar structure and function)
C. ORGANS (groups of tissue working to do a specific job)
D. ORGAN SYSTEMS (a group of organs working together)
E. INDIVIDUAL ORGANISM ( a living thing that carries out life processes)

THE DIGESTIVE SYSTEM
AKA “Gastrointestinal Tract (GI)
 Converts foods into simpler molecules, then absorbs them into the blood stream for use by cells

SALIVARY GLANDS
 Teeth – cut & grind food
 Salivary Glands – moisten mouth & food with saliva , which has amylase (an enzyme) to break down starches

 Esophagus – food tube leading to stomach
 Peristalsis – smooth muscle contracts to push food into stomach (also moves food through small intestines)

Large musular sac which:
 secretes mucus (to protect stomach)
 secretes hydrochloric acid ( which activates pepsin to digests protein)
 churns food & liquid into “ chyme ”

 Where most of the chemical digestion & absorption of nutrients occurs
 Villi – tiny projections that increase surface area for absorption of nutrients

 Also called the colon
PERISTALSIS
 Water is removed from the digested materials leaving the small intestine to form solid waste
 Makes Vitamin K

 Holds solid wastes, called feces , until they exit the body through the anus

A. SALIVARY GLANDS
B. MOUTH
C. ESOPHAGUS
D. STOMACH
Liver
E. LARGE
INTESTINE
H. ANUS
Pancreas
F. SMALL INTESTINE
G. RECTUM


Largest internal organ

Secretes bile (helps digest fat)

Stores excess glucose as glycogen


Secretes digestive fluids and insulin (which helps balance glucose in the blood stream)


Stores bile until needed by the small intestines to digest lipids

LIVER
GALL
BLADDER stomach
PANCREAS

System of vessels and/or spaces through which blood and/or lymph fluid flows in a human
.

Has three (3) main parts:
A. the heart
B. blood vessels
C. blood

-
A liquid tissue consisting of plasma and blood cells in a suspension.
- Transports nutrients, dissolved gases, enzymes, hormones & waste products

Red blood cells
(erythrocytes)
White blood cells (leukocytes)
Most numerous, disk-shaped, carries O
2 to all cells in the body. Carries a protein called
HEMOGLOBIN
Larger in shape than RBCs but fewer in number. Helps immune system fight off pathogens.

platelets
(AID IN CLOTTING)
Plasma Yellowish liquid part of blood made up of
90% WATER & 10% PLASMA
PROTEIN, DISSOLVED FAT,
SALT AND SUGAR

B. BLOOD VESSELS -
1. Arteries - vessels that carry blood AWAY from the heart.
2. Capillaries - thin-walled blood vessels in which most of the exchange of gas, nutrients & wastes takes place.
3. Veins - vessels that RETURN blood to the heart. Have valves!!!

Section 37-1
Artery
Artery
Figure 37-5 The Three Types of Blood Vessels
Capillary Vein
Vein
Capillary Endothelium
Arteriole Venule
Connective tissue
Smooth muscle
Endothelium
Connective tissue
Smooth muscle
Valve
Endothelium

A. The Heart
1. Main pump of the circulatory system
2. Move Blood THROUGH the BODY
3. Surrounded by a loose-fitting sac called the pericardium .
4. Has four chambers: Right &
Left Atria and Right & Left Ventricle

Pulmonary artery
Right atrium
(contains the pacemaker sends electric impulses that causes heart muscles to contract)
Right ventricle : pumps blood from the heart to the lungs
AORTA: transp orts O
2 rich blood from the left ventricle to the body
Pulmonary artery
Pulmonary vein
Left atrium receives O
2 rich blood from the lungs
Left Ventricle pumps O
2 rich blood to the body .
Septum-thick muscle that separates right half of heart from left half.

Blood Pressure measure of the force that blood exerts against a vessel wall

I
T
E
N
S
H
Y
P
E
R
O
N

ATHEROSCLEROSISNARROWED
ARTERIES DUE TO PLAQUE (FATTY
DEPOSITS), CAN CAUSE HEART ATTACK OR
STROKE.
HYPERTENSION-
(“high blood pressure”) occurs when the force of blood pumping through vessels is too great.
Anemia when the blood transports too little oxygen.

SICKLE-CELL DISEASE
Red Blood Cells are misshapened causing blood cells to “CLOG” vessels. Hereditary
Leukemia a form of cancer where bone marrow produces immature stem cells in large numbers & releasing them into the bloodstream.

TAKING CARE OF THE HEART

THE RESPIRATORY SYSTEM
 Exchanges oxygen and carbon dioxide between the blood, air & tissues

 Entryway for air

Common pathway for food and air.

 Flap that closes off the trachea when swallowing (prevents choking)

 Voice box containing vocal cords

 Tube lined with cartilage rings
(carries air to lungs) trachea

 Branch off from trachea into each
 lung bronchi bronchioles

 Grape-like air sacs responsible for exchanging gases with the blood

 Have large surface area for gas exchange
LUNG
CANCER
EMPHYSEMA
HEALTHY
LUNG

 Muscular sheet that contracts to bring air into & relaxes to push air out of the lung

NOSE
BRONCHIOLES
PHARYNX
MOUTH
LARYNX
TRACHEA
ALVEOLI
DIAPHRAGM
BRONCHI
LUNGS

Air in
Air out
Ribs rise
Ribs fall
Diaphragm
Mechanisms of Breathing

:
the process that helps the body maintain homeostasis by disposing of wastes in the body.

Kidneys: act as filters for all of the liquid waste in the body.
ADRENAL GLANDS Ureters: tubes that connect the kidneys to the bladder and transport urine to the bladder.
Urinary bladder: elastic sac that is used to store and then remove urine
(liquid waste)
Urethra: single tube that allows the bladder to release the urine out of the body.

Although Lungs and Skin are major organs of other organ systems.
They are also a part of the Excretory System.
Lungs: excrete carbon dioxide waste as we exhale.
Skin: excretes sweat through the pores in our skin.

*
COVERS YOUR BODY
• CONSISTS OF SKIN AND ITS GLANDS, HAIR
AND NAILS
* SKIN IS BODY’S LARGEST ORGAN
* PROTECTS & INSULATES THE BODY






F UNCTIONS OF H UMAN I NTEGUMENTARY S YSTEM
1. Barrier against infection and injury
2. Help regulate body temperature
3. Remove waste products from body
4. Provide protection against ultraviolet radiation
5. Produces vitamin D
Epidermis
Dermis
Skin Model

EPIDERMIS: Skin’s outer layer
* COVERED WITH PORES
* SWEAT & OIL SECRETED
* TOP LAYER - FLAT, DEAD CELLS REPLACED
EVERY 28 DAYS
* KERATIN – WATERPROOF PROTEIN THAT KEEPS
BACTERIA FROM ENTERING

DERMIS: Thick inner layer yer
1.
MAKES COLLAGEN
2. PRODUCES MELANIN (pigment)
3. CONTAINS NERVE ENDINGS,BLOOD VESSELS,
HAIR FOLLICLES & SEBACEOUS GLANDS
(sebum = oil)
4. SWEAT GLANDS

1. Protects the scalp from UV rays
2. Protects the tips of fingers and toes

Can you believe we have 206 bones?
~ Skull and upper jaw 21 bones
~ 3 tiny bones in each ear
~ Lower jaw (mandible)
~ Front neck bone (hyoid)
~ Backbone or spine (26 separate bones or vertebrae)
~ Ribs (12 pairs - same number for men and women)
~ Breastbone
~ Each upper limb has 32 bones: 2 in shoulder, 3 in arm, 8 in wrist,
19 in hand and fingers.
~ Each lower limb has 31 bones: 1 in hip (one side of pelvis), 4 in leg, 7 in ankle, 19 in foot and toes

FUNCTION:
1. Support
2. Protection
3. Movement
4. Storage of minerals
5. Production of blood cells

PARTS OF THE BONE:
A. PERIOSTEUM - living membrane covering bone
B. SPONGY BONE- tissue with many spaces, located at end of long bones & in middle of flat bones - gives strength without adding mass.
C. COMPACT BONE - very dense, located in shafts of long bones – resists mechanical shock.

D. Marrow - soft tissue that fills some space in bone
1. Red - produces RBC
2. Yellow - mostly fat cells

CARTILAGE: connective tissue found in many parts of the body – reduces friction in moveable joints.
TENDONS – connective tissue that attaches muscle to bone
LIGAMENTS – connective tissue that attaches bone to bone at joints.

Spongy Bone
Compact Bone
Bone Marrow
Cartilage

Function a. Muscles contract and shorten b. Provide motility c. Move substances through body- heart, blood vessels & digestion d. Muscle tone – maintain posture and keep organs in place.
e. Muscles generate heat when they are worked

T HREE T YPES OF M USCLE T ISSUE
Muscle Type Location in Body
Skeletal
Voluntary
Usually attached to bone; found all around the body
Smooth Found in walls of blood vessels &
Involuntary digestive tract
Cardiac Only found in heart; has properties of
Involuntary both skeletal & smooth muscle
Skeletal Smooth Cardiac

Skeletal - enables movement of body parts a. Voluntary b. Striated c. Multinuclei d. Attached to bone e. Bundled cells

a
. Involuntary b. Not striated c. Only 1 nucleus per cell d. Regulates other systems

a. Striated b. Involuntary c. Can contract without nervous stimluation

H UMAN M USCULAR S YSTEM
•
•
–

Interaction of Muscles, Bones, and Nerves:
Nerves cells communicate with muscle fibers, causing them to contract and do work.
Skeletal muscles attach to bone by tendons and are found in pairs. When one contracts, the opposite muscle relaxes, creating strength and flexibility .
When a muscle contracts, its length gets shorter.
When it relaxes, it gets longer .

Consists of: brain, spinal cord, nerves and sense organs
Sense Organs: Eyes, Skin, Ears, Nose & Tongue

Main Function:
This communication system controls and coordinates functions throughout the body and responds to internal and external stimuli.
Our nervous system allows us to feel pain.

A nerve is an organ containing a bundle of nerve cells called neurons.
Neurons carry electrical messages called impulses throughout the body.
Picture shows hundreds of severed neuron axons

Because neurons never touch, chemical signalers called neurotransmitters must travel through the space called synapse between two neurons.
Neurotransmitters (pink spheres)
The message is transferred when
RECEPTORS receive neurotransmitters .
Synapse
(gap)

P ARTS OF A N EURON
1.
Cell body : contains nucleus & most of the cytoplasm
2.
3.
Dendrites : projections that bring impulses into the neuron to the cell body.
Axon : long projection that carries impulses away from cell body
2 3
1

Sensory Neuron
Interneuron
Motor Neuron
Interneuro n
Synapse
Synapse
Motor
Neuron
Sensory
Neuron
Synapse
Muscle
Contracts

A reflex is an involuntary response that is processed in the spinal cord not the brain.
Reflexes protect the body before the brain knows what is going on.

Consists of: Brain and Spinal Cord
Cerebrum brai n
Cerebellum
Medulla Oblongata
Spinal Cord

Cerebrum
Cerebellum
Medulla Oblongata
(Brain Stem)
Voluntary or conscious activities of the body-learning, judgment
Coordinates and balances the actions of the muscles
Controls involuntary actions like blood pressure, heart rate, breathing, and swallowing
Spinal Cord
The main communications link between the brain and the rest of the body

Consists of: Sensory division and Motor division
-includes all sensory neurons, motor neurons, and sense organs

 Main Function:
It releases hormones into the blood to signal other cells to behave in certain ways. It is a slow but widespread form of communication.

P ITUITARY G LAND
Function : It secretes nine hormones that control all other endocrine glands.
-produces human growth hormone
Disorders : Too much growth hormone can result in a condition called gigantism.
Robert
Wadlow

T HYROID G LAND
 Hormone : Thyroxin
 Function : plays a major role in the regulation the body’s metabolism.
 Disorders :
Hyperthyroidism -too much thyroxin; fast metabolism
Hypothyroidism - too little thyroxin; slow metabolism

P ANCREAS
 Function : Produces insulin to keep the blood sugar level constant.
 Disorders : Diabetes disease in which the pancreas fails to produce insulin or the body does not properly use Insulin

A DRENAL G LAND
 Functions :
-The adrenal glands release Adrenaline in the body that helps prepare for and deal with stress.
-Also regulates kidney function.

O VARIES
 Functions :
 Pair of reproductive organs found in women that produce eggs.
 Also secrete estrogen and progesterone , which control ovulation and menstruation.

T ESTES
 Functions:
 Pair of reproductive glands that produces sperm.
 Also secrete Testosterone to give the body its masculine characteristics.

I NTERACTION OF G LANDS
The brain and glands work together to maintain homeostasis through a process called negative and positive feedback mechanisms
.
The feedback the brain gets is from the information it collects as the hypothalamus monitors the bloodstream.
Using this information, the brain knows what hormones to start and stop releasing.

I NTERACTION OF G LANDS
The feedback the brain gets is from the information it collects as the hypothalamus monitors the bloodstream.
Using this information, the brain knows what hormones to start and stop releasing.

Urethra
Male reproductive system

TESTES: the male organs that produce sperm cells and the hormone Testosterone responsible for secondary male characteristics such as facial hair, deepening of voice, broad shoulders.
EPIDIDYMIS
TESTIS
SCROTUM

SCROTUM: located outside the body
-protects the testes
- keeps them slightly cooler than body temperature
- important for sperm cell development & survival.

A duct that transports sperm from the epididymis to the ejaculatory duct & urethra. It is the structure that is cut during a vasectomy.

PROSTATE GLAND: one of many glands and vesicles that produce seminal fluid.s.

head
Middle section
Tail
(flagellum)
Small, motile gametes produced in the testes and used for reproduction - ~ 700 million produced each day

PENIS: (surrounds the urethra)
Made of spongy erectile tissue that expands when filled with blood.
Propels semen (containing sperm, fructose & other fluids made by the prostate gland) during ejaculation .
Semen also cleanses the urethra

Urethra
Male reproductive system

Reproductive system - female

:
Fallopian Tubes
Ovary
Uterus
Cervix
Vagina
Ovary
Labia

The female organ that usually releases one ovum (egg) a month
Contains about 400,000 follicles which is where the egg develops and matures .
Produces the hormones estrogen and progesterone – give females their secondary sex characteristics such as soft voice, breasts, pubic hair …..

Fallopian tubes:
Pathway through which an egg travels to the uterus.
Fertilization occurs here.
Structure that is cut/tied during a tubal ligation .

Muscular, pear-shaped organ where the fetus develops .
Cervix connects the uterus to the vagina
Inner layer called the endometrium where fertilized egg plants itself.

* Tube shaped organ that opens to the outside of the body
* Receives the penis during intercourse - it is also where sperm enters.
* Serves as the birth canal where the baby exits the body.

THE MAIN FUNCTIONprotects the body from pathogens (sickness).
Also to distinguish “ self ” cells from
“ non-self ” cells.

Any virus, bacteria or parasite that causes infectious disease.

HOW ARE DISEASES TRANSMITTED?

The immune system has two main defenses:

Non-specific (first & second line) defenses:
- Skin (inc.
hair and nails, body secretions…)
- Inflammatory Response (Inflammation, fever, itching caused by Histamines)

Specific (third line) defenses:
Humoral Immunity and Cell-Mediated Immunity

Non-Specific Defenses:
(1 st line of defense):
Skin: include nails and hair,
Body Secretions: mucous, tears, sweat and saliva
Body Openings: mouth, nose, pores

Second Line of Non-specific Defense:
Inflammation: (called the Inflammatory
Response) a reaction to tissue that is damaged caused by injury or infection.
Chemicals called histamines are released signaling macrophages to come and kill the pathogen that is trying to spread into the body.
Fever: an increase in the body’s core temperature.
Redness & swelling

Steps of inflammatory response
See p. 1037 - book

S PECIFIC D EFENSES : 3 RD L INE OF D EFENSE

There are 2 main specific defenses:
Humoral Immunity and Cell-mediated
Immunity.

HUMORAL IMMUNITY
Fight pathogens in body fluids
Involves B cells and antibodies (Y-shaped proteins) which mark specific antigens for destruction. Some B cells become memory B cells .
B-cell Plasma B-cells
Helper B Cells
Lysis

CELL-MEDIATED IMMUNITY
White blood cells (T-lymphocytes) directly attack harmful cells.
In cell-mediated immunity, Helper T cells bind to infected cells to signal Killer T cells to come and attack the infected cells. The Killer T cells can kill the infected cell along with the
Pathogen by destroying (lysing) the membrane of the cell.

There are 3 kinds of T-cells...
Killer T-cells...Helper T-cells...and
Suppressor T-cells

Helper T-cells call in more
Killer T-cells to kill germs, and tell the
B-cells when to make antibodies

Lymphatic System: Stores, circulates & produces WBC.
Lymph: fluid that collects in lymphatic capillaries and slowly flows into larger lymph vessels.
Lymph Vessels: structures that contain valves to keep lymph from flowing backwards.
Lymph Nodes : small beanlike structures that act as filters trapping bacteria and other microorganisms
Tonsils filter & destroy bacteria while lymph is returned via ducts.
The thymus secretes a hormone that helps the WBC mature.
The spleen filters dead red blood cells

Tonsils
Thymus Gland
Spleen
Lymph Nodes
Lymph Vessels