Organ SystemsOrgan SystemsForm meets FunctionForm meets Function

The organ systems of the human body and other vertebrates help to maintain balance and perform a variety of functions.

The Body Worlds exhibit of preserved human bodies and allows visitors to view the amazing human body in never before seen ways.

This unit will introduce the major parts and functions of each of the body systems.

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Levels of Organization The levels of organization in a

multicellular organism include cells, tissues, organs, and organ systems

Cells the basic unit in living things; specialized cells perform particular functions (EX heart cell)

Tissues are groups of similar cells that perform a single function (EX connecting muscle to bone)

An Organ is a group of tissues that work together to perform a complex function (EX Eyes for sight)

An organ system is a group of organs that perform closely related functions (EX the digestive system)

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Cells Cells can be specialized (have a certain function Function = job Function is related to the cell structure Structure = how parts of the cell are put

together Shape Material it’s made from

Structure of a brain cell is different from muscle cell

Can you tell which cells are neurons, fat, leukocytes, bone (osteocytes, skeletal muscle, smooth muscle, cardiac muscle, cubodial (roll up to make tubes)

There are four basic types of tissues in the human body Epithelial tissue - Glands and tissues that cover interior and

exterior body surfaces Connective tissue - Provides support for the body and connects

its parts Nervous tissue - Transmits nerve impulses throughout the body Muscle Tissue - Along with bones, helps the body to move

Types of Tissues

Examples of Epithelium TissueExamples of Epithelium Tissue

Examples of Connective Tissue

Examples of Examples of Nervous TissueNervous Tissue

Examples of Muscle Tissue

Organs

Organ Systems There are 11 organ systems of the human body that work

together to maintain homeostasis in the body

Homeostasis is the process by which organisms keep internal conditions relatively stable despite changes in external environments Muscular system Skeletal system Nervous system Circulatory system Respiratory system Endocrine system Lymphatic/Immune system Digestive system Excretory system Integumentary system Reproductive system

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Muscular System Function:

Works with the skeletal system to produce voluntary movement; helps to circulate blood and move food through the digestive system

Major Structures: Skeletal Muscles – usually

attached to bones and help with voluntary movement

Smooth Muscles – found in the walls of hollow structures (stomach, blood vessels, intestines) and NOT under voluntary control

Cardiac Muscles – found only in the heart and NOT under voluntary control Works Closely With: the skeletal

system to move the body, with the help of signals from the nervous system

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Muscle AnatomyIf you were to take one whole muscle and cut through it, you would find the muscle is covered in a layer of connective muscle tissue known as the Epimysium that protects the muscle from friction against other muscles and bones.

Organization of the Skeletal Organization of the Skeletal MuscleMuscle

Surrounding the muscle fiber is the Sarcolemma = fibers cell membrane then the Sarcoplasm = cells cytoplasm, containing Glycogen, Fats and Mitochondria for energy. Each muscle fiber itself contains cylindrical organelles known as Myofibrils.

Myofibrils made up ofbundles of Actin andMyosin proteins whichrun the length of themuscle fiber and areImportant in musclecontraction known asthe sliding filament theory.

Organization of the Skeletal Organization of the Skeletal MuscleMuscle

Muscles in Action

SKELETAL SYSTEMSKELETAL SYSTEMThree types of Skeletal systems are:

Hydrostatic

Exoskeleton

Endoskeleton

Skeletal System Function: Supports the body; locomotion of

voluntary muscles, protection of organs; helps to maintain calcium levels; provides a site for blood cell formation

Major Structures: Bones, joints, cartilage,

ligaments, tendons Types of Cells:

Osteoblasts – build and produce new bone Osteoclasts – break down bone Bone Marrow – within the hollow center of bones, produces red

and white blood cells and platelets Works Closely With: the 206 bones in the adult body works with the

muscular system to move the body

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Work on your worksheets!Work on your worksheets!

Skeletal System In the outline of the

Homo sapien on your Skeletal Systems page draw and label the following structures: clavicle, femur, fibula, humerus, patella, pelvis, radius, ribs, scapula, skull, sternum, tibia and ulna.

Nervous System Function: Recognizes and

coordinates the body’s responses to changes in its internal and external environment

Major Structures: Central Nervous System = brain & spinal cord and Peripheral Nervous System = cranial nerves, ganglia and spinal nerves

Types of Cells: Neurons – send the messages of the nervous system though electrical impulses

Works Closely With: sensory receptors and the five senses (sight, sound, smell, taste, and touch) to interpret stimuli from the environment

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Central and Peripheral SystemsCentral Nervous System (CNS) consists of the brain and spinal cord. - sensory information goes down the dorsal roots - motor information goes down the ventral roots to the muscles and glands

dorsal root ganglion (ganglia, plural) "Gray matter" in middle = cell bodies

"White matter" surrounding = insulated axons

Central and Peripheral SystemsPeripheral Nervous System (PNS) receives signals from the spinal cord and transmits the message by way of peripheral nerves. Peripheral nerves in the cervical region serve the neck and arms; those in the thoracic region serve the trunk; those in the lumbar region serve the legs; and those in the sacral region serve the bowels and bladder.

The PNS consists of

somatic nervous system that connects voluntary skeletal muscles with cells specialized to respond to sensations, such as touch and pain

autonomic nervous system is made of neurons connecting the CNS with internal organs. It is divided into

- sympathetic nervous system which prepares the body for action: fight or flight

-parasympathetic nervous system helps to restore the body, build up energy & supplies needed in the

future, and relax

Typical Neuron and Synapse

Read the excerpts from the article entitled “Neuron” and very briefly describe the four steps of a nerve impulse down a neuron.

Typical Neuron and Synapse cont

Reflex Arc• A reflex arc is the pathway that a nerve reflex, such as the knee jerk reflex, follows. A tap on the knee stimulates sensory receptors, generating a nerve signal. The signal travels along a nerve to the spinal cord. In the spinal cord, the signal is transmitted from the sensory nerve to a motor nerve. The motor nerve sends the signal back to a muscle in the thigh. The muscle contracts, causing the lower leg to jerk upward. The entire reflex occurs without involving the brain.

Place the number next to the correct part

FUNCTION

Occipital Lobe Center for processing visual and spatial information

Medulla the end of the spinal chord is where many involuntary actions, heart beating, breathing, digestion, are regulated

Temporal Lobe Center for processing auditory and temporal (time-related) information

Limbic System Manages the transition between sleep and arousal

Thalamus Involved in the processing of emotion and strong drives like sex, fear and hunger.

Cerebral Cortex A region of high neuron concentration, divided into the following lobes, (one on each side of the brain).

Parietal Lobe Various functions, including processing of physical sensation and new movements. Bottom of parietal lobe contains olfactory bulb, = taste/smell

Hypothalamus Helps control what information reaches the frontal lobes, regulates flow of consciousness and attention

Cerebellum Where information for performing learned movements are stored.

The Frontal Lobes Where thought occurs. Both are centers for memory, learning, problem-solving, feeling, awareness, and decision-making. The left side = analytical; right side = "open-ended" understanding and thinking

Cerebo-spinal Fluid

Produced by glands in the brain to act as a protective cushion.

Circulatory System Function - Brings oxygen, nutrients, and

hormones to cells; fights infection; removes cells wastes; helps to regulate body temperature

Major Structures - Heart, vascular system made up of blood vessels (arteries & veins), blood Heart Video

Types of Cells - Red blood cells – transport O2 & CO2

White blood cells – fight infection Platelets – allow blood to clot and

stop bleeding

Works Closely With: the respiratory system in gas exchange; digestive system to pick up and carry nutrients to the cells of the body the excretory system to filter and clean the blood the endocrine system to deliver hormones

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Close Up of a Blood Vessel

The connective blood vessels of the body carry the cells of the circulatory system

The vessels can sometimes become blocked with plaque (fatty buildup) shown in yellow

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Sounds of the Circulatory System

The heart muscle contacts an average of 72 times per minute, sending blood throughout the body through a series of blood vessels.

Sound File

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Function: Provides oxygen needed for cellular respiration and removes excess carbon dioxide from the body

Major Structures: Upper respiratory tract – the nasal cavity, pharynx and larynxLower respiratory tract – the trachea, bronchi and lungs

Key Parts:Nose and nasal cavities, mouth, larynx, trachea, bronchi and their

branches, diaphragm, and the alveoli Works Closely With:

the circulatory system in gas exchange and the muscular system for inhalation and exhalation.

Respiratory System

Parts of the Respiratory System

Within each lung, the tiny alveoli are surrounded by blood vessels and oxygen and carbon dioxide diffuse in and out of the vessels.

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With each breath, air enters our body through the air passageways and fills up our lungs.

Digestive System Function:

Converts foods into simpler molecules that can be used by the cells of the body; absorbs nutrients; eliminates fecal matter

Major Structures: Mouth, pharynx, esophagus,

stomach, small and large intestines, rectum

Key Parts: Villi – folded structures within

the walls of the intestines which allow for nutrient exchange

Works Closely With: circulatory system to deliver nutrients to the cells of the body

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Close UP of Digestive Villi

The villi projections allow as much of the nutrients in the digestive system to move in to the circulatory system, providing energy for cells.

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Digestive Enzymes

The pH in the human digestive tract varies greatly.  The pH of saliva is usually between 6.5  -  7.5.  After we chew and swallow food it enters the stomach, pH 4.0 - 6.5.  This is where "predigestion" occurs. Just before leaving the stomach, near the pyloric sphincter, hydrochloric acid (HCI) and pepsin are secreted reaching a pH between 1.5 - 4.0.  Food mixes with these juices and enters the small intestine where the pH changes to 7.0 - 8.5. This is where 90% of the nutrients are absorbed and the waste products are passed out through the large intestine, pH 4.0 - 7.0.

Function: Eliminates urine and other by-

products from the body while maintaining homeostasis

Major Structures: Skin, lungs, kidneys, ureters,

urinary bladder, urethra Key Parts:

Kidneys – remove waste products from the blood

Bladder – collects urine (wastes filtered through the kidney)

Works Closely With: the circulatory system to filter and clean the blood

Excretory System

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AP Biology 2007-2008

Immune / LymphaticSystem

lymphocytesattackingcancer cell

phagocytic leukocyte

lymphsystem

Fighting theEnemy Within!

AP Biology

Why an immune system? Attack from outside

lots of organisms want you for lunch! animals are a tasty nutrient- & vitamin-packed meal animals must defend themselves against invaders (pathogens)

Viruses, bacteria, Fungi, Protists

Attack from inside cancers (abnormal body cells)

Function protects body from diseaseprotects body from disease collects fluid lost from blood vessels & collects fluid lost from blood vessels &

returns it to the circulatory systemreturns it to the circulatory systemMmmmm,What’s in your lunchbox?

AP Biology

Lymph system Works closely with the circulatory system to fight infection and collect excess fluids

lymph node

lymph vessels(intertwined amongst blood vessels)

MajorStructures:

AP Biology

Development of Red & White blood cells

short-lived phagocytes60-70% WBC

develop into macrophages

inflammatory response

fightparasites

Red blood cells

Lymphocytes

Leukocytes

White blood cells

AP Biology

Innate vs Acquired ImmunityINNATE

• present before any exposure to pathogens

• effective from the time of birth

• largely nonspecific and slow to respond to specific microbes

External: Skin, Mucous membranes, Secretions

Internal: Phagocytic Cells, Antimicrobial proteins, Inflammatory response and Natural Killers

ACQUIRED

• develops only after exposure to microbes, abnormal body cells, toxins or other foreign substances

• highly specific because Lymphocytes (white blood cells) produce two types of immune responses

Humoral: cells derived from B cells secrete defensive proteins call antibodies

Cell-mediated: T cells directly destroy infected body and cancer cells, and foreign tissue

AP Biology

Lines of defense 1st line: Non-specific barriers

broad, external defense “walls & moats”

skin & mucous membranes 2nd line: Non-specific patrols

broad, internal defense “patrolling soldiers”

leukocytes = phagocytic WBC 3rd line: True immune system

specific, acquired immunity “elite trained units”

lymphocytes & antibodies B cells & T cells

Bacteria & insectsinherit resistance.Vertebratesacquire immunity.

AP Biology

1st line: Non-specific External defense Barrier

skin

Traps mucous membranes, cilia,

hair, earwax

Elimination coughing, sneezing, urination,

diarrhea

Unfavorable pH stomach acid, sweat, saliva, urine

Lysosome enzyme digests bacterial cell walls tears, sweat

Lining of trachea: ciliated cells & mucus secreting cells

AP Biology

2nd line: Non-specific patrolling cells Patrolling cells & proteins

attack pathogens, but don’t “remember” for next time leukocytes

phagocytic white blood cells macrophages, neutrophils,

natural killer cells

complement system proteins that destroy cells

inflammatory response increase in body temp. (fever) increase capillary permeability attract macrophages yeast

macrophage

bacteria

AP Biology

Inflammatory response (local non—specific trigger when tissue is damaged)

AP Biology

Specific defense with memory lymphocytes

B cells T cells

antibodies immunoglobulins

Responds to… antigens

cellular name tags specific pathogens specific toxins abnormal body cells (cancer)

3rd line: Acquired (active) ImmunityB cell

AP Biology

Antibodies

Proteins that bind to a specific antigen multi-chain proteins binding region matches molecular shape of antigens each antibody is unique & specific tagging “handcuffs”

“this is foreign…gotcha!”

each B cell has ~50,000 antibodies

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antigenantigen-binding site on antibody

variable binding region

AP Biology

Lymphocytes B cells

mature in bone marrow humoral response system

“humors” = body fluids attack pathogens still circulating

in blood & lymph produce antibodies Types: Plasma and Memory cells

T cells mature in thymus cellular response system

recognize and attack invading cells Types: Helper, Killer and Memory T Cells

bone marrow

AP Biology

Vaccinations Immune system exposed

to harmless version of pathogen stimulates B cell system to produce

antibodies to pathogen “active immunity”

rapid response on future exposure creates immunity

without getting disease!

Most successful against viruses

AP Biology

Jonas Salk Developed first vaccine

against polio attacks motor neurons

1914 – 1995April 12, 1955

Albert Sabin1962oral vaccine

AP Biology

Polio epidemics

1994: Americas polio free

AP Biology

Obtaining antibodies from another individual maternal immunity

antibodies pass from mother to baby across placenta or in mother’s milk

critical role of breastfeeding in infant health mother is creating antibodies against pathogens baby

is being exposed to

Injection injection of antibodies short-term immunity (rabies shot)

Passive immunity

AP Biology

Human Immunodeficiency Virus virus infects helper T cells

helper T cells don’t activate rest of immune system: killer T cells & B cells

also destroys helper T cells

AIDS: Acquired ImmunoDeficiency Syndrome infections by opportunistic

diseases death usually from

“opportunistic” infections pneumonia, cancers

HIV & AIDS

HIV infected T cell

Endocrine System Function:

Controls growth, development, and metabolism; maintains homeostasis

Major Structures: Hypothalamus, pituitary, thyroid,

parathyroid, adrenals, pancreas, and gonads (ovaries in females, & testes in males)

Key Parts: Hormones – chemicals released in

one part of the body and travel to affect other parts

Works Closely With: the nervous system which controls the release of hormones and the circulatory system to deliver them

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GLAND: HypothalamusLOCATION: Ventral part of the forebrain.

HORMONE: Secretes releasing or inhibiting hormones that act directly on the tissues of the pituitary gland.

FUNCTION: It is the control center for many autonomic functions of the peripheral nervous system. Connections with structures of the endocrine and nervous systems enable the

hypothalamus to play a vital role in maintaining homeostasis. As a limbic system structure, it influences various emotional responses.

GLAND: PituitaryLOCATION: Bean sized structure that dangles on a slender stalk of tissue at the base of the skull. The gland is divided into two parts: anterior and posterior

HORMONE: Secretes hormones that directlyregulate many body functions and controlsthe actions of several other endocrine glands.

FUNCTION:Posterior Pituitary

OxytocinAntidiuretic (Vasoperssin)

Contraction of uterus and releases milkTells kidneys to reabsorb water

Anterior Pituitary

GrowthProlactinFSH (Follicle-stimulating)

LH (Luteinizing)

TSH (Thyroid-stimulating)

ACTH (Adrenocorticotropic)

Protein synthesis and growth in bonesProduction of Breast MilkStimulates production of ova and spermOvaries and testesStimulates the thyroid glandTells adrenal cortex to secrete glucocorticoids

GLAND: THYROID & PARATHYROID

LOCATION: Base of neck and wraps around the upper part of the trachea.HORMONE: Thyroid Hormone (Triiodothyronine (T3) and Thyroxine (T4)

CalcitoninFUNCTION: Stimulate and maintain Basal Metabolic Rate (BMR), which is

the amount of energy the body usesLowers blood calcium level

LOCATION: The four glands are found on the backsurface of the thyroid gland.

HORMONE: Parathyroid hormoneFUNCTION: Raises blood calcium level

GLAND: PancreasLOCATION: Just behind the

stomach; upper left quadrant

HORMONE: InsulinGlucagon

FUNCTION: Cluster of cells called islets of Langerhans

contain beta cells which secrete insulin and lower blood glucose levels and alpha cells which secrete glucagon and raise blood glucose levels

GLAND: AdrenalLOCATION: Two pyramid-shaped structures that

sit on top of thekidneys; each glandhas an outer part, adrenal cortex, and an inner part, adrenal medulla

HORMONE: Epinephrine and norepinephrineGlucocorticoids and Mineralocorticoids

FUNCTION:

AdrenalMedulla

Epinephrine (adrenalin) and Norepinephrine (noradrenalin)

Raise blood glucose level, increase metabolic activities, constricts some blood vessels; prepares the body for “fright, fight or flight”

AdrenalCortex

Aldosterone (GlucocorticoidsMineralocorticoids

Raise blood glucose levelsPromote reabsorption of Na+ and excretion of K+ in kidneys

GLAND: GonadsLOCATION: Female – inside pelvis cavity

Male – outside pelvic cavity HORMONE: Androgens, Estrogen,

ProgesteroneFUNCTION: Production of gametes and

secretion of sex hormones

Testes Androgen(Testosterone)

Support sperm formation, promote development and maintenance of male secondary sex characteristics

Ovaries Estrogen

Progesterone

Stimulate uterine lining growth, promote development and maintenance of female secondary sex characteristics

Promotes uterine lining growth

Function: Protection is the most important

function. It serves as a barrier against infection and injury

Major Structures: Skin, hair, and nails

Key Parts: Epidermis – outer layer of skin Dermis – inner layer of skin Hair – protects the skin and filters

particles Nails – extension of the skin, grow 3

mm per day on average Works Closely With: nervous system

through the five senses

Integumentary SystemImage

Integumentary System cont.The Skin is the human body's Largest Organ. The word INTEGUMENT comes from a LATIN word that means to

COVER. FIVE Other Functions of the Integumentary System

1. Serves as a barrier against infection and injury. 2. Helps to regulate body temperature. 3. Removes waste products from the body. 4. Provides protection against UV radiation from the sun. 5. Produces vitamin D.

The skin contains sensory receptors through which sensations such as pressure, heat, cold, and pain are transmitted to the nervous system.

The skin is made up of two main layers – the epidermis and the dermis. Beneath the dermis is a subcutaneous layer of fat.

EPIDERMIS1. The outer most layer of skin , composed of five layers and four types of cells.

2. Most of the cells of the Epidermis undergo rapid cell division (MITOSIS) and are shed or washed away once every 14 to 28 days.

3. As new cells are produced, they push older cells to the surface of the skin. The older cells become flattened, lose their cellular contents and begin making Keratin.

4. Keratin is a tough fibrous protein and forms the basic structure of hair, nails and calluses. In animals it forms horns, scales, feathers, and quills.

5. The Epidermis contains melanocytes, cells that produce melanin, a dark brown pigment.

6. There are no blood vessel in the epidermis, which is why a small scratch will not cause bleeding.

DERMIS1. Second layer of skin composed of living cells. 2. Connective tissue layer composed of collagen and elastic fibers, fibroblasts,

macrophage and fat cells, hair follicles, glands, nerves and blood vessels. 4. Beneath the Dermis is the

Hypodermis, (Subcutaneous layer), a

layer of fat and looseconnective tissue thatinsulate the body andacts as an energy reserve.

5. The Dermis contains TWOmajor types of GLANDS: Sudiferous (sweat) and Sebaceous (oil) Glands.

6. Oil Glands are connected byTiny Ducts (Exocrine Glands)to Hair Follicles. Sebum coats the surface of the skin and the shafts of hair, preventing excess water loss and lubricating and softening the skin and hair.

HAIR1. Hair is produced by cells at the base of structures called Hair Follicles.

Hair protects and insulates the body.2. Hair Follicles are tube-like pockets of epidermal cells that extend into

the dermis. Tiny Muscle fibers attach to Hair Follicles contract and pull hair upright when you are cold or afraid, producing Goose Bumps.

3. Individual hairs are actuallylarge columns of dead cellsfilled with Keratin.

4. Rapid cell growth in the Hair Root causes hair togrow longer. Hair gets itscolor from Melanin.

5. Hair Follicles are in close contact with Sebaceous Glands.

NAILS Nails grow from an area of rapidly dividing cells know as the Nail

Matrix or Nail Root and is located near the tips of the fingers and toes.

Nails rest on a bed of tissue filled with blood vessels, giving the nails apinkish color.

Nails grow at a rate of 0.5 to 1.2 mm perday, with fingernails growing fasterthan toenails.

Place the number on the diagram on your worksheet

Reproductive Systems Function:

Produces reproductive cells; in females, nurtures and protects developing embryo

Major Structures:Testes, epididymis, vas deferens, urethra, and penis (in males); ovaries, Fallopian tubes, uterus, vagina (in females)

Types of Cells: Sperm Cells – male reproductive cells created in the male reproductive systemOva – female egg cells created in the female reproductive system

Works Closely With: endocrine system to receive sex hormones Slideshow of Conception

fetus at 8 weeks

Testes develop in the abdomen and descend into the scrotum just before birth. This is important since sperm can not develop at normal body temperature and must be kept approximately 2° C lower.

Scrotum - fold of the body wall which aids the reproductive process in different ways:

Fig. 46.9

Ovaries are the female gonads. Located in the abdominal cavity and enclosed in a

tough protective capsule. Attached by mesentery to the uterus. Each ovary contains follicles.

The remaining female reproductive structures are:

Cervix: neck of the uterus, that opens into the vagina.

Vagina: thin-walled chamber that forms the birth canal.