ANAPHY-Introduction to the Human body

Anatomy

• Science of body structures and the relationships among them

• Initially studied through dissection

Physiology

• Science of body functions

• How the body parts work

Chemical, Cellular, Tissue, Organ, System, Organismal Level

Levels of Structural Organization

Chemical Level

very basic level

Atoms

smallest units of matter participating in chemical reactions

Carbon, Hydrogen, Oxygen

give three ex. of atoms

Molecules

2 or more atoms joined together

ex. Deoxyribonucleic acid (DNA), Glucose

Cellular Level

Molecules combine to form cells

cells

• basic structural and functional units of an organism composed of chemicals

• smallest living units in the human body

• eg. Epithelial cells, muscle cells

Tissue level

• A group of cells and the materials surrounding them that work together to perform a particular function

Epithelial, Connective, Muscular, Nervous

What are the 4 basic types of tissues?

Epithelial tissue

covers the body surfaces; lines hollow organs and cavities; forms glands

skin, lining of organs

examples of epithelial tissue (2)

Connective tissue

connects, supports, and protects organs while distributing BVs to other tissues

fats, bones, ligaments, tendons, cartilage

examples of connective tissue (5)

Muscular tissue

contracts to make body parts move and generate heat

smooth muscle, heart muscle, skeletal muscle

examples of muscular tissue (3)

Nervous tissue

carries information from 1 part of the body to another thru nerve impulses

brain, sciatic nerve

examples of nervous tissue (2)

sciatic nerve

It is the longest and largest nerve in the body

Organs

• composed of 2 or more different types of tissues

• have specific functions and recognizable shapes

• ex. stomach, skin, bones, heart

Organ Level

different types of tissues are joined together

System Level

• consists of related organs with a common function

• All ________ influence one another

• Sometimes, an organ can be part of more than one

11

There are a total of ___ systems

Organismal Level

• Organism: any living individual

• consists of all parts of the body functioning together

Noninvasive Diagnostic Technique

• surface assessment without inserting any instrumental or device thru the skin or body opening

• can be done thru: Inspection, Palpation, Auscultation, Percussion

Inspection

• physical appearance

• checking or observing the patient

Palpation

• touch the patient (always ask for consent)

Auscultation

• medical practice of listening to internal body sounds

• primarily using a stethoscope

Percussion

a physical exam technique where a doctor taps the body to listen for sounds

Basic Life Processes

• certain processes distinguish living organisms from nonliving things

Metabolism, Responsiveness, Movement, Growth, Differentiation, Reproduction

What are the 6 most important life processes?

Metabolism

• sum of all chemical processes occurring in the body

• 2 phases: Catabolism and Anabolism

Catabolism

breakdown of complex chemical substances to simpler components

Anabolism

building up of complex chemical substances from smaller, simpler components

Responsiveness

• body’s ability to detect and respond to changes

• different cells respond to environmental changes in characteristic ways

• Nerve cells respond by generating electrical signals (nerve impulses)

• Muscle cells respond by contracting —> generating force to move body parts

Movement

• includes motion of whole body, individual organs, single cells, and even tiny structures inside the cells

Growth

• Increase in body size

• tissues may increase in size due to the amount of material between cells

Hyperplasia

• increase in cell number

• excessive growth or overproduction of cells in a normal tissue or organ

Hypertrophy

• increase in cell size

• enlargement of an organ or tissue due to an increase in the size of its individual self

Differentiation

• development of a cell from unspecialized to specialized state

• 2 types of stem cells: Embryonic and Adult

Stem cells

precursor cells that divide and give rise to cells that undergo differentiation

Embryonic stem cells

Pluripotent and can differentiate into nearly any cell type

Adult stem cells

Multipotent with more limited differentiation potential

Reproduction

• formation of new cells for tissue growth, repair, or replacement through cell division

• Production of a new individual through fertilization

Homeostasis

• The ability to maintain internal stability in an organism in response to environmental changes

Homeostasis

• a self-regulating process that controls internal variables necessary to sustain life.

Endocrine, Nervous systems

2 major systems of homeostasis

maintaining the homeostasis

The endocrine and nervous systems are essential in __________ of the body.

maintain a balance within the body

What is the most important function of homeostasis?

body fluids

dilute watery solutions with dissolved chemicals found inside cells and surrounding them

intracellular fluid, extracellular fluid

2 types of body fluids

Intracellular fluid

fluid within cells

extracellular fluid

fluids outside the body cells

interstitial fluid

ECF filling the narrow spaces between cells of tissues

blood plasma

ECF w/in blood vessels (BVs)

Lymph

w/in lymphatic vessels

cerebrospinal fluid

in and around the brain and spinal cord

synovial fluid

in joints

aqueous humor

water-like fluid in front of the lens

vitreous body

gel-like substance behind the lens

Body fluids

• The proper functioning of the body depends on precise regulation of the composition of their surrounding fluid.

external environment

• space that surrounds the entire body

internal environment

ECF surrounds the cells of the body

true

T or F: Homeostasis is continually disturbed

Physical insults

disruptions from the external envt (intense heat during summer; lack of O2 for a 2-mile run)

disruptions from the internal environment

low blood sugar from skipping breakfast

imbalance from psychological stress

demands of work and school

Nervous system

• sends electrical signals known as nerve impulses (action potentials) to organs that can counteract changes from the balanced state

• typically cause rapid changes

Endocrine system

includes many glands that secrete messenger molecules (hormones) into the blood

feedback systems

• a cycle of events in which the status of the body is monitored, evaluated, changed, remonitored, reevaluated, etc.

monitored variable

body temperature, BP, blood sugar level are examples of?

controlled variable

controlled condition

stimulus

• any disruption that changes a controlled condition

• ex. sudden drop in temperature, sudden lack of oxygen

brain

it is the control center of our body

receptor, control center, effector

3 basic components of feedback system

receptor

• body structure that monitors changes in a controlled condition and sends input to a control center: Afferent pathway

Afferent pathway

information flows toward the control center

input

is in the form of nerve impulses or chemical signals

control center

evaluates the input it receives from receptors and generates output commands when they are needed

brain

sets the narrow range or set point within w/c a controlled condition should be maintained

output from the control center

typically nerve impulses, hormones, or chemical signals

efferent pathway

information flows away from the control center

effector

• body structure that receives output from the control center and produces a response or effect that changes the controlled condition

• nearly every organ or tissue in the body can be an ______

• ex. body temp drops sharply —> brain (control center) sends nerve impulses (output) to skeletal M —> shivering to generate heat and raise temp

Negative feedback system

Reverses a change in a controlled condition (opposite)

Positive feedback system

• strengthens or reinforces a change in one of the body’s controlled condition

• action continues until interrupted by some mechanism or until optimal condition is obtained

• ex. labor - more oxytocin —> more contraction

homeostatic imbalances

• when the cells in our body do not work correctly, homeostatic balance is disrupted

• _____________ may lead to a state of disorder or disease or death

genetics, diet, side effects of medicines, toxins

4 factors that affect homeostasis

disorder

any abnormality in structure or function

disease

more specific term for an illness characterized by a recognizable set of signs and symptoms; alters structures and functions in a characteristic way

local

affects 1 part or limited region of the body

systemic

affects entire body or several parts of it

symptoms

subjective changes in body functions not apparent to observer; eg. nausea, anxiety

signs

objective changes observed and measured by an examiner

anatomical

swelling, rash

physiological

fever, high BP, paralysis