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
• “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