Organization of the Human Body Chapter 1 Organization of the Human Body

Human Body Understanding the normal body is basis for analyzing disease Structure Functions

Studies of the Human Body Anatomy Study of body structure Physiology Study of body function

Levels of Organization Chemicals Cells Tissues Organs Body systems Organism

Checkpoint 1-1: In studying the human body, one may concentrate on its structure or function. What are these two studies called? Anatomy and physiology

Body Systems Protection, support and movement Coordination and control Integumentary Skeletal Muscular Coordination and control Nervous Endocrine Circulation Cardiovascular Lymphatic Nutrition and fluid balance Respiratory Digestive Urinary Production of offspring Reproductive

Metabolism and Its Regulation Types of metabolism Catabolism Complex substances are broken down into simpler compounds Nutrients in food broken down into compounds used by the body for growth, repair and energy Anabolism Simple compounds used to make materials used for growth, function and tissue repair Amino acids used to make proteins

Metabolism

Homeostasis Fluid balance Extracellular – fluids outside the cells Blood Lymph Interstitial fluid (fluid between the cells)

Homeostasis Feedback Control system based on returning information to the source Negative Keeps body conditions within a normal range by reversing any upward of downward shift Positive A given action promotes more of the same Continues until stimulus stops or an outside force stops it

Negative feedback. The classic example used to illustrate negative feedback is the house thermostat . As in any feedback loop, there is a stimulus (temperature change), a sensor (a thermometer), a comparator (the thermostat setting), and an effector (the furnace).

Negative feedback in the endocrine system. When glucose increases in the blood (as in after a meal), the pancreas secretes insulin, which causes body cells to use more glucose. The subsequent drop in blood sugar level signals the pancreas to reduce insulin secretion. As a result of insulin’s reaction, the secretion of insulin is reversed.

Comparison of positive and negative feedback In negative feedback, the result of an action reverses the stimulus. In positive feedback, the result of an action stimulates further action. This positive feedback continues until the stimulus is removed or an outside force stops the cycle.

The Effects of Aging Obvious Not visible Wrinkles Gray hair Decreased kidney function Loss of bone mass Formation of deposits in blood vessels

Checkpoint 1-2: Metabolism is divided into a breakdown phase and a building phase. What are these two phases called? Catabolism – compound substances broken down into simpler compounds Anabolism – Simple compounds are used to manufacture needed materials

Checkpoint 1-3: What type of system is mainly used to maintain homeostasis? Negative feedback

Directions in the Body Consistent terms are used to designate position and direction to avoid awkwardness and inaccuracy.

Directional Terms Superior Ventral (anterior) Dorsal (posterior) Above or in a higher position The head is the superior part of the body Ventral (anterior) Toward the front of the body (belly) The sternum is in the ventral part of the thorax Dorsal (posterior) Toward the back of the body The sacrum is in the dorsal part of the pelvis Cranial Toward the head Caudal Toward the feet Toward the tail in four-legged animals

Directional Terms Medial Lateral Proximal Distal Toward the midline of the body The tibia is medial to the fibula Lateral Toward the side of the body The humerus is lateral to the clavicle Proximal Nearer the origin of a structure The elbow is proximal to the wrist The proximal part of the alimentary canal is the mouth Distal Farther away from the origin The knee is distal to the hip The distal part of the stomach is called the pylorus

Directional terms ZOOMING IN •What is the scientific name for the position in which this subject is standing? The anatomical position

Planes of Division Frontal (coronal) Sagittal Transverse (horizontal) Divides the body into anterior and posterior parts Sagittal Divides the body into right and left parts The mid-sagittal plane divides the body into EQUAL right and left halves Transverse (horizontal) Divides the body into superior and inferior parts

Planes of division. ZOOMING IN •Which plane divides the body into superior and inferior parts? Transverse (horizontal) Which plane divides the body into anterior and posterior parts? Frontal (Coronal)

Tissue Sections Cross section Longitudinal (transverse) section Cut made perpendicular to the long axis A cut across a sausage to make a circle Longitudinal (transverse) section Cut made parallel to the long axis Cutting a banana lengthwise to make a banana split Oblique section Cut made at any angle

Tissue sections.

Cross-sections in imaging Images taken across the body through the liver and spleen by Computed Tomography (CT)

Checkpoint 1-4: What are the three planes in which the body can be cut? Frontal, sagittal, transverse What kind of plane divides the body into halves? Mid-sagittal

Body Cavities Internally, the body is divided into spaces, or cavities, that contain organs. The two main cavities are the dorsal and ventral cavities

Body cavities, lateral view. ZOOMING IN • What cavity contains the diaphragm? Thoracic cavity

Dorsal Cavity Two main cavities Cranial Spinal Contains the brain Contains the spinal cord

Ventral Cavity Has two main cavities separated by diaphragm Thoracic Pericardial cavity Pleural cavity Mediastinum Abdominopelvic Abdominal (superior) cavity Pelvic (inferior) cavity

The thoracic cavity.

Checkpoint 1-5: There are two main body cavities, one posterior and one anterior. Name these two cavities. Posterior – dorsal Anterior - ventral

Regions of the Abdomen Epigastric Umbilical (navel) Hypogastric Right and left Hypochondriac Right and left Lumbar Right and left Inguinal (iliac)

Quadrants of the Abdomen Right upper Left upper Right lower Left lower

The nine regions of the abdomen.

Quadrants of the abdomen.

Checkpoint 1-6: Name the three central regions and the three left and right lateral regions of the abdomen. Central regions Epigastric Umbilical (navel) Hypogastric Lateral regions Right and left Hypochondriac Right and left Lumbar Right and left Inguinal (iliac)

The Metric System Each multiple is indicated by a prefix. Kilo- X 1,000 Centi- 1/100 Milli- 1/1,000 Micro- 1/1,000,000

Units of Length Meter Kilometer (km) Centimeter(cm) Millimeter(mm) The basic unit of length is the meter (m) Kilometer (km) Equal to a 1000 meters Centimeter(cm) Equal to 1/100 of a meter (there are 100 centimeters in a meter Millimeter(mm) Equal to 1/1000 of a meter (there are 1000 millimeters in a meter)

Comparison of metric and British systems 1 mm = 0.04 inch, or 1 inch = 25 mm 1 cm = 0.4 inch, or 1 inch = 2.54 cm 1 m = 3.3 feet, or 1 foot = 30 cm

Units of Weight Gram(g) Kilogram(kg) Milligram(mg) The basic unit of weight 30 g are about equal to 1 ounce Kilogram(kg) 1 kilogram = 1000 gram 1 kilogram = 2.2 pounds (lb) Milligram(mg) 1 milligram = 1/1000 gram (1 gram = 1000 mg) Drug doses are usually stated in g or mg.

Units of Volume Liter Milliliter Basic measure for volume One liter is equal to 1.06 quarts Milliliter There are 1000 ml in one liter 5 ml = 1 teaspoon 15 ml = 1 tablespoon 1 fluid oz contains 30 ml

Temperature Celsius (centigrade) scale To convert Celsius to Fahrenheit °F = 9/5 °C + 32 Ex. To convert 35 °C to °F °F = (9/5 x 35) + 32 = 63 + 32 = 95 °F To convert Fahrenheit to Celcius °C = 5/9 (°F –32) Ex. To convert 80 °F to °C °C = 5/9(80 – 32) = 5/9 (48) = 26.8 °C

Checkpoint 1-7: Name the basic units of length, weight, and volume in the metric system. Length Meter Kilometer Centimeter Millimeter Weight Gram Kilogram Milligram Volume Liter Milliliter