CH.1 The study of body function

steps of scientific Method

1. Observation, 2. hypothesis, 3. prediction, 4. experiment, 5. analyze, 6. conclude, 7. Modify and Repeat, 8. share

how many phases in human tirals?

3 phases of clinical study on humans

what are the 3 phases of clinical study on humans?

Phase1: test drug on healthy human volunteers Phase2: test drug on people with particular dieasease (target population) Phase3: test on large number of people phase4: test other applications for drug

Components of Feedback loops

Sensors, integration center, effector

skeletal muscle tissue

Voluntary, has cell organized in striations, most associated with bones of the skeleton that are pulled to produce movement.

cell potency

a cell's ability to differentiate into other cell types.

hypothesis

a tentative explanation for a specific phenomenon that has been observed

theory

a widely accepted explanatory idea or statement that is wide in scope and supported by a large body of evidence.

multipotent

ability to differentiate into a limited to a narrow range of possibilities that can become several related cells. e.g. bone marrow cells can become any type of blood cell

toipotent

ability to differentiate into any cell type e.g. zygotes

pluripotent

ability to differentiate into any of the three germ layers-ectoderm, mesoderm, and endoderm e.g. embryonic cells

hypodermis

adipose tissue for padding and insulation: not technically a part of the skin

simple columnar epithelium

allows for absorption as found in the wall of the small intestine.

simple squamous epithelium

allows for rapid diffusion as in the alveoli of the lungs

simple cuboidal epithelium

allows for secretion of substances as in various glands

intracellular

area inside the cells: contains 65% of total body water

extracellular

area outside the cells; contains 35% of total body water

integrating center

assesses change around a set point and sends instructions to an effector

stem cells

basic and general cells that are undifferentiated and can dfferentiate into specialized calls and can divide to make more stem cells.

cell

basic unit of structure and function of living things

organism

being where all systems work in coordination

positive feedback

causes the action of the effectors to amplify the changes away from homeostasis

Negative feedback

causes the action of the effectors to counteract the changes e.g. body temp.

Levels of organization

cell, tissue, organ, system, organism.

intrinsic regulation

cells "built into" the organs being regulated sense a change and signal to neighboring cells to respond appropriately.

bone

cells called osteoblasts trap mineral salts, forming concentric layers of calcified material around a central canal filled with blood vessels and nerves.

connective tissue

characterized by a matrix made up of protein fibers, extracellular material, and specialized cells

loos(areolar) connective tissue

collagen fibers scattered loosely with room for blood vessels and nerves--hypodermis of skin and holding organs in place.

cartilage

composed of cells called chondrocytes trapped in spaces called lecunae surrounded by a semi-solid ground substance: non-vascularized.

connective tissue proper

composed of protein and a gel like ground substance

Homeostasis

constancy of the internal environment.

dermis

dense irregular connective tissue containing exocrine glands, hair follicles, sense receptors, and blood vessels.

dense regular connective tissue

densely packaged collage fiber with regular pattern appearance and little room for ground substance--tendons and ligaments.

dense irregular

densely packaged collagen fiber with irregular pattern appearance-deep dermis of skin

glands

derived from cells of epithelial membranes

sensors

detect change and send information to the integrating center.

epithelial tissue

forms the membranes that cover body surfaces, line inside or hollow organs, and glands;

Nervous Tissue

found in brain, spinal cord, and nerves. composed of neurons and neuroglia.

smooth muscle tissue

found in walls of digestive, urinary and reproductive organs, blood vessels, and bronchioles of lungs (hollow organs), not striated, involuntary

cardiac muscle Tissue

found only in heart, fibers are short, branched, and interconnected both physically and electrically. striated, involuntary

system

group of organs that work together to perform related functions.

tissue

group of similar cells that perform similar function

organ

group of two or more tissues that make up structural and functional units.

what are the organ systems?

integumentary, nervous, endocrine, skeletal, muscular, circulatory, immune, respiratory, urinary, digestive and reproductive system.

epidermis

keratinized stratified squamous epithelium to protect against water loss and abrasion

antagonistic effectors

maintain homeostasis by opposing effectors that move conditions in opposite directions which causes a dynamic constancy. e.g. when you are hot, you sweat.

effector

makes the appropriate adjustments to counter the change from the set point.

stratified epithelia tissue

multiple layers that provide protection

simple epithelial tissue

one layer specialized for transport of substances

stratified epithelial tissues

provide protection, cells of tissue are held together by structures called junctional complexes.

endocrine glands

secrete chemicals called hormones into capillaries within the tissue

exocrine glands

secrete chemicals through a duct to outside of a membrane

differentiated cells

specialized cells

Muscle Tissue

specialized for contraction; 3 types: skeletal muscle, cardiac muscle and smooth muscle

adipose connective tissue

specialized type of loose connective tissue

principle

statement or fact meant to explain in concise terms and action or set of actions; generally to be true and universal

vivo studies

studies on animals to see if same effect occurs in vivo(within a living create) and if there are any toxic effects.

Physiology

study of biological function; how the body works

comparative physiology

study of comparative functions of various animals

Pathophysiology

study of how disease or injury alters physiological processes

vitro studies

studying the effects of a chemical on cells in vitro (cells cultured outside of body)

teeth

the dentin of tooth is similar to bone and is made by cells in the pulp; the outer enamel is harder than bone or dentin

extrinsic regulation

the nervous or endocrine systems regulate the organ. (effect on multiple organs)

tissue development

tissues composed of highly specialized cells that arise from three embryonic germ layers: endoderm:internal layer mesoderm-middle layer ectoderm-outside layer