study of structure and shape of the body and its parts and their relationships with one another
all the structures (muscles, bones, blood vessels, nerves, etc.) in particular region of the body, such as the abdomen or leg, are examined at the same time
a subdivision of developmental anatomy, concerns developmental changes that occur before birth
Levels of Structural Organization
1. Chemical Level: Atoms combine to form molecules
2. Cellular Level: Cells are made up of molecules
3. Tissue Level: Tissues consist of similar types of cells
4. Organ Level: Organs are made up of different types of tissues
5. Organ System Level: Organ systems consist of different organs that work together closely
6. Organism Level: Human organisms are made up of many organ systems
tiny building blocks of matter, combine to form molecules such as water, sugar, and proteins
a structure composed of two or more tissue types that performs a specific function for the body
the living body composed of all 11 organ systems; highest level of structural organization. represents the sum total of all structure levels working together to keep us alive.
the external covering of the body, or the skin
Functions: waterproofs the body, protects deeper tissue, helps regulate body temperature
consists of bones, cartilages, ligaments, and joints
Functions: supports the body, provides framework, causes movement
the muscles of the body; skeletal muscles for the muscular system
Functions: to contract or shorten, for movement to occur
the body's fast-acting control system. Consists of the brain, spinal cord, nerves, and sensory receptors
Functions: sensory receptors detect stimuli from outside and inside the body, and send these messages to the central nervous system (brain, spinal cord) so that it is informed about what is going on
control body activities; endocrine glands produce chemical molecules called hormones and release them into the blood to travel to relatively distant target organs.
the primary organs of this system are the heart and blood vessels
Functions: carries oxygen, nutrients, hormones, and other substances to and from the tissue cells where exchanges are made
complements that of the cardiovascular system
Functions: picks up fluid leaked from blood vessels and returns it to blood, houses white blood cells
a tube running through the body from mouth to anus. Organs include oral cavity, esophagus, stomach, small and large intestine, and rectum.
Functions: break down food and deliver the products to the blood for dispersal to the body cells
removes the nitrogen containing wastes from the blood and flushes them from the body in urine. This system is composed of the kidneys, ureters, bladder, and urethra.
Other Functions: maintains body's water and salt (electrolyte) balance, and regulating the acid-base balance of the blood
exists primarily to produce offspring.
Males: Testes produce sperm. Scrotum, penis, accessory glands, and the duct system
Females: Ovaries produce eggs. Consists of uterine tubes, uterus, and vagina
the body's ability to maintain relatively stable internal conditions even though the outside world changes continuously; dynamic state of Equilibrium
all homeostatic control mechanism are processes involving at least 3 components that work together
receptor, control center, effector
some type of sensor that monitors the environment and responds to changes called stimuli, by sending information (input) to the control center along the afferent pathway
determines the set point, which is the level or range at which a variable is to be maintained, and information (output) then flows from the control center to the effector along the efferent pathway
Negative Feedback Mechanism
the output shuts off the original effect of the stimulus or reduces its intensity- goal: preventing sudden severe changes within body.
* (hormonal by endocrine system) control of blood volume by antidiuretic hormone. as blood volume drops, receptors in the body sense this change, and the hypothalamus of the brain stimulate the release of ADH to the blood. this change in turn prompts the kidneys to reabsorb more water and return it o the bloodstream. the rising blood volume then ends the stimulus for ADH release.
Positive Feedback Mechanism
the result or response enhances the original stimulus so that the response is accelerated. also called cascades because of the waterfall effect it has.
Disturbance of Homeostasis, when usual negative feedback mechanisms are overwhelmed and destructive positive feedback mechanisms take over. *heart failure
example of positive feedback
enhancement of labor contractions and blood clotting. Labor: as contractions increased more oxytocin released.
the body is erect with feel slightly apart, palms facing forward and the thumbs point away from the body.
allows us to explain where one body structure is in relation to another. *lateral, superior, ventral(anterior), etc
dorsal body cavity
which protects the fragile nervous system organs, divided by cranial cavity and vertebral cavity
principle of complementary of structure and function
what a structure can do depends on its specific form.
* bones can support and protect body organs because they contain hard mineral deposits.
Necessary life functions
maintaining boundaries, movement, responsiveness, irritability, digestion, metabolism, reproduction, and growth.
maintaining its boundaries
so that its internal environment remains distinct from the external environment surrounding it.
activities promoted by the muscular system, on the cellular level the muscle's cells ability to move by shortening is more precisely called contractility
ability to sense changes (in the stimuli) in the environment and then respond to them.
*if you cut your hand on broken glass, a withdrawal reflex occurs-you involuntarily pull your hand away from the painful stimulus.
it the breaking of ingested foodstuffs to simple molecules that can be absorbed into the blood. the nutrient-rich blood is then distributed to all body cells by the cardiovascular system.
"state of change" is broad term that includes all chemical reactions that occur within body cells and regulated by hormones secreted by endocrine system glands.
occurs at the cellular and organismal level. cells divide producing two identical daughter cells then maybe then used for body growth or repair.
goal: is to maintain life. (nutrients, oxygen, water, normal body temperature, appropriate atmospheric pressure)
60-80% of body for body secretions and excretions. lose it by evaporation from the lungs and skin in body excretions
normal body temperature
must be maintained. as it drops below the norm, metabolic reactions become slower and slower and finally stop. when it is too high, chemical reactions occur at a frantic pace and body proteins lose their characteristic shape and stop functioning.