Chapter 1 Notes

The Human Organism

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Overview of Anatomy and Physiology

• Anatomy– the scientific discipline that investigates

the body’s structure. Ex. Anatomy describes the shape and size of bones.

• Physiology– the scientific investigation of the

processes or functions of living things.

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Types of Anatomy• Gross Anatomy- structures examined

without a microscope.– Systemic- studied system by system.– Regional- studied area by area.– Surface- external form and relation to deeper

structures as x-ray in anatomic imaging.

• Microscopic Anatomy- structures seen with a microscope.– Cytology: cellular anatomy.– Histology: study of tissues.

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Topics of Physiology

• Reveals dynamic nature of living things.• Considers operations of specific organ

systems.– Cell physiology- examines processes in cells– Neurophysiology- focuses on the nervous

system– Pathology– Exercise Physiology

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Structural & Functional Organizations

• Chemical level– Atoms– Molecules

• Cell level• Tissue level• Organ level• Organ system level• Organism level

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Terminology and the Body Plan

• Anatomical Position- body erect, face forward, feet together and palms face forward

• Other Body Positions– Supine: lying face

upward.– Prone: lying face

downward.

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Directional TermsSuperior- A structure above another.Inferior- A structure below another.Anterior- The front of the body. Posterior- The back of the body.Dorsal-Back area. Ventral-Stomach area.Proximal- Closer to the point of attachment to the

body than another structure.Distal- Farther from the point of attachment to the

body than another structure.Medial- Toward the midline of the body.Lateral- Away from the midline of the body.Superficial- Toward or on the surface. Deep- Away from the surface, internal.

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Body Terms

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Characteristics of life• Organization- condition in which there are

specific relationships and functions.• Metabolism- all chemical reactions of the

body.• Responsiveness- ability to sense changes and

adjust.• Growth• Development- changes over time.

– Differentiation- change from general to specific.

– Morphogenesis- change in shape of tissues, organs.

• Reproduction- new cells or organisms.

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CONCEPT CHECK!1. What is the difference between anatomy and

physiology?-A: study of the structures & parts of an organism-P: study of the processes & functions

2. What are the levels of organization of living things? Describe them.

-cells, tissues, organs, organ systems, organisms

3. What is metabolism?-all the chemical reactions in the body

4. What is the difference between growth and development?

-growth: increase in height or mass-development: changes over time (differentiation &

morphogenesis)

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Body Parts and Regions• Upper limb- consists of the arm, forearm,

wrist, & hand.

• Lower limb- consists of the thigh, leg, ankle, and foot.

• Central region of body- consists of the head, neck and trunk.– Trunk: divided into the thorax (chest), abdomen,

and pelvis.

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Body Planes• Sagittal plane- divides the body vertically into

right & left portions– Midsagittal/Median- divides the body into equal

right and left halves.– Parasagittal- runs vertically through the body to one

side of the midline

• Transverse (Horizontal)- divides the body into superior & inferior portions.

• Frontal (Coronal)- divides the body into anterior and posterior parts.

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Body Cavities• Thoracic Cavity- surrounded by the rib cage

– Mediastinum- contains the heart, thymus gland, trachea, esophagus, blood, & vessels.

– Diaphragm- large muscle that separates upper & lower cavities

• Abdominal Cavity– Contains the stomach, intestines, liver, spleen, pancreas, and

kidneys.

• Pelvic Cavity– Contains the urinary bladder, part of the large intestines, and

the internal reproductive organs.

• Ambdominopelvic- large double cavity below breathing muscle

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Serous Membranes

• Serous membranes- covers the organs & lining of the trunk cavities.– Visceral-thin membrane that covers the organs

within the cavity.– Parietal- wall of body cavity that covers its surface.

• Pericardial cavity- surrounds the heart

• Pleural cavity- surrounds each lung.

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Systems of the BodySystems Studied • Integumentary-consists of skin, hair, nails & sweat glands• Skeletal-protects/supports body, produces blood cells, & stores

minerals (bones)• Muscular-consists of muscles (movement)• Nervous-consists of brain & spinal cord, nerves & receptors• Vascular-blood• Circulatory-consists of the heart and blood vessels• Respiratory-exchanges gases btn the blood & air & regulates

blood pH• Digestive-breaks down food & absorbs nutrients• Reproductive-ability to reproduce new offspring

Not Studied…But still important to the body • Endocrine-consists of glands that secrete hormones• Lymphatic-maintains tissue fluid balance & absorbs fat• Urinary-removes waste products from the circulatory system &

regulates blood pH

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Homeostasis• Values of variables

fluctuate around the set point to establish a normal range of values.

• Set point- the ideal normal value of a variable.– What is the set point

for body temperature?

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Negative Feedback

• Most systems of the body are regulated by negative-feedback mechanisms that maintain homeostasis.

• 3 Components– Receptor: monitors the value of some

variable (Ex. Blood Pressure)– Control Center: establishes the set point

around which the variable is maintained– Effector: can change the value of the

variable.

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Negative Feedback

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Positive Feedback• When a deviation occurs, response is

to make deviation greater.– Leads away from homeostasis.– Can result in death.