A&P: Unit 1Body Organization

11 Organ Systems of the Body

Integumentary System• Includes: The skin• Function: Protects

deeper tissue, regulates body temperature, synthesizes Vitamin D

11 Organ Systems of the Body

Muscular System• Includes: Skeletal

muscles, cardiac muscles, smooth muscles, and tendons

• Function: contract to allow movement, maintains posture

11 Organ Systems of the Body

Skeletal System• Includes: Bone,

Cartilage, Ligaments, Joints

• Function: Supports body, Protects certain cavities, Stores minerals

11 Organ Systems of the Body

Digestive System• Includes: Mouth,

Esophagus, Stomach, Small and Large Intestine, Rectum, and Liver

• Function: Breaks down food to deliver nutrients to the body cells; undigested food leaves body as feces

11 Organ Systems of the Body

Respiratory System• Includes: Nasal

Passages, Pharynx, Larynx, Trachea, Bronchi, and Lungs

• Function: Supplies blood with oxygen and removes carbon dioxide

11 Organ Systems of the Body

Cardiovascular System• Includes: Heart, Blood

Vessels (Veins, Arteries, and Capillaries)

• Function: Carries oxygen, carbon dioxide, nutrients, hormones, wastes, etc. through the body in blood

11 Organ Systems of the Body

Nervous System• Includes: Brain,

Spinal Cord, Nerves, and Sensory Receptors

• Function: detect and respond to internal & external changes by activating appropriate muscles and glands

11 Organ Systems of the Body

Urinary System• Includes: Kidneys,

Ureters, Bladder, and Urethra

• Function: Eliminates nitrogenous wastes from the body, maintains body’s water and salt balance, regulates pH of the blood

11 Organ Systems of the Body

Lymphatic System• Includes: Lymphatic

vessels, Lymph Nodes, Spleen, Thymus, Tonsils

• Functions: Picks up fluid leaked from blood vessels and returns it to blood, cleanses blood, house white blood cells (involved with immunity)

11 Organ Systems of the Body

Endocrine System• Includes: Glands -

including pineal, pituitary, thyroid, thymus, adrenal, pancreas, testis (males), and ovaries (females)

• Function: secretion of hormones that regulate body activities (growth, reproduction, and metabolism)

11 Organ Systems of the Body

Reproductive System• Males

Includes: testes, scrotum, penis, glands, duct system

Function: Produces sperm and carries to the outside of the body

11 Organ Systems of the Body

Reproductive System, con’t• Females

Includes: uterus, ovaries, fallopian tubes, vagina

Function: Produces eggs, serves as locations for fertilization and development of the fetus

Levels of Organization• From smallest unit to largest unit:

– Chemical Level: atoms and compounds– Cells: smallest unit of all living things– Tissues: similar cells with common function

• There are 4 types of tissue – Epithelial, Connective, Muscle, and Nervous

– Organ: composed of two or more tissue types

– Organ System: organs that cooperate to accomplish a common goal

– Organism: highest level of organization

Homeostasis

• The body’s ability to maintain relatively stable internal conditions – needed for life

• “homeo-” is unchanging, “-stasis” is standing still

• This is another goal that your organ systems work together to achieve

Homeostasis

• With homeostasis, your body isn’t really “standing still”, but it’s trying to!

• It’s like a tight-rope walker – you want to stay on the wire, but sometimes other forces affect you (the wind, a slippery rope, noises, etc.)

• You must react to overcome the forces and re-balance yourself over the wire.

• Homeostasis works the same way…• It attempts to keep an internal balance within

your body.

Homeostasis

• Communication/coordination within the body is achieved mainly by the Nervous and Endocrine Systems, but many of the systems participate in some extent

• A response is triggered by some change in the norm

Homeostasis

• Most control mechanisms are “Negative Feedback Systems” – inhibit a change– Examples include body temperature, heart

rate, blood pressure, breathing rate, and blood levels of gases & nutrients

Homeostasis

Homeostasis

• “Positive Feedback Systems” are rare because they actually try to push your body out of the normal balance to react to an event that has occurred

• Examples include…

Homeostasis

• Birth– Oxytocin (causes contractions) is released

due to pressure on the cervix– Ends when the fetus is expelled

• Bleeding– clotting yields more clotting, which is

eventually stopped by stopped blood flow

Homeostasis

Language of Anatomy

• Terms with precise meanings are used to help medical and healthcare professionals communicate effectively with one another about the human body.

• You are responsible for the following terms and being able to apply them!

Language of Anatomy

• Anatomical Position– Feet parallel– Arms hanging at sides– Palms facing forward– Thumbs pointing away

from body

• Don’t forget… his left is on your right-hand side!!!

RIGHT LEFT

Body Position

• Supine– Laying Face-up

• Prone– Laying Face-Down

Directional Terms

• Superior (Cranial)– Toward the head– Above

• Inferior (Caudal)– Away from the Head– Below

Directional Terms

• Anterior (Ventral)– Toward the front of the

body– In front of

• Posterior (Dorsal)– Toward the back of the

body– Behind

Directional Terms

• Medial– Toward midline– Inner side

• Lateral– Away from midline– Outer Side

Directional Terms

• Intermediate– Between a medial and

lateral structure

Directional Terms

• Proximal– Closer to the

attachment point of a limb to the body trunk

• Distal– Farther from the

attachment point of a limb to the body trunk

Directional Terms

Directional Terms

• Superficial– Towards the body

surface

• Deep– Away from the body

surface– More internal

Directional Terms

• Ipsilateral– On the same side of

the body

• Contralateral– On opposite sides of

the body

Planes of the Body

• Median (Midsagittal) Plane – divides into equal right and left sections

• Frontal (Coronal) Plane – divides into anterior and posterior parts

• Transverse Plane – divides into superior and inferior parts

Body Cavities

• What kinds of organs might be found in the Dorsal Cavity?

• What kinds of organs might be found in the Ventral Cavity?– Which of these organs

would be specific to the Thoracic Cavity?

– To the Abdominopelvic Cavity?

Abdominopelvic Cavity

• Why would this cavity be vulnerable to damage?

• Because it is so large, it is helpful to break up this cavity into smaller sections for study

• One system used by medical personnel uses quadrants

Abdominopelvic Cavity

• Another system used by anatomists, divides it into 9 regions– “epi” is upon, “gastric”

is stomach– “hypo” is below– “Iliac” is the superior

part of hip bone– “lumbus” is loin– “chondro” is cartilage