The Human Body: An Orientation

Chapter 1
Name the different levels of structural organization that make up the human body- from micro to macro
organ system
organismal level
What is the Chemical Level in relation to the structural organization of the human body?
the simplest level. Made up of atoms that combine to form molecules such as water and proteins
What is the cellular level in relation to the structural organization of the human body?
the smallest living units.
Define Tissues
groups of similar cells that have a common function.
What are the 4 basic tissue types?
connective tissue
nervous tissue
What does the epithelium cover?
the body surface and lines the cavities of hollow organs
What is the function of muscle tissue?
What is the function of connective tissue?
supports and protects the body organs
What is the function of nervous tissue?
provides a means of rapid internal communication by transmitting electrical impulses
What makes up an organ?
at least two tissue types that perform a specific function for the body
What is the organ system level?
organs that are working together to accomplish a common purpose
What is the organismal level?
the highest level and represents the sum total of all structural levels working together to keep humans alive.
What is the principle of complementarity of structure and function?
function always reflects structure.
What are the necessary life functions?
maintain boundaries
respond to environmental changes
take in and digest nutrients
carry out metabolism
dispose of wastes
What does it mean to maintain boundaries?
keeping internal environment remains distinct from the external environmental surroundings.
What organ system maintains boundaries?
The Integumentary system
How does the body provide movement?
from the muscles pulling on the skeletal system
What is responsiveness or irritability?
the ability to sense changes in the environment and then respond to them.
What is digestion?
the breaking down of ingested foodstuffs to simple molecules that can be absorbed into the blood.
What is metabolism?
a broad term that includes all chemical reactions that occur within the body cells.
What is catabolism?
Breaking down
What is anabolism
synthesizing (building up)
How is metabolism regulated?
by the hormones secreted by the endocrine system glands.
How many organ systems does the human body have?
Name the 12 organ systems
Integumentary system
skeletal system
muscular system
nervous system
endocrine system
cardiovascular system
lymphatic system
respiratory system
digestive system
urinary system
Male reproductive system
female reproductive system
What is excretion?
the process of removing wastes from the body
What are the two types of reproduction?
Cellular reproduction and organismal reproduction
What is cellular reproduction?
the dividing of cells to produce identical daughter cells
What is growth?
an increase in size of a body part or the organism
How many survival needs does a human have
Name the 4 survival needs of humans
normal body temp
appropriate atmospheric pressure
Define homeostasis
a dynamic state of equilibrium
What is homeostatic control
communication within the body
What are the parts of the homeostatic control system?
the receptor
the control center
the effector
Define variable
the factor or event being regulated
what is a receptor?
a type of sensor that monitors the environment and responds to stimuli
What are the 5 stages of the homeostatic control system?
1. stimulus produces change in variable
2. receptor detects change
3. input information sent along afferent pathway to control center
4. output information sent along efferent pathway to effector
5. response of effector feeds back to reduce the effect of stimulus and returns variable to homeostatic level.
What is the purpose of the integumentary system?
external body covering
protects deeper tissues from injury
synthesizes vitamin D
houses sweat and oil glands
What is the purpose of the skeletal system?
protects and supports body organs
provides framework for the muscles to use to cause movement
blood cells are formed within the bones
store minerals
What is the purpose of the muscular system?
allows manipulation of the environment
facial expression
maintains posture
produces heat
What is the purpose of the nervous system?
fast acting control system of the body
responds to external and internal changes by activating appropriate muscles and glands
What is the purpose of the endocrine system?
glands that secrete hormones that regulate growth, reproduction, and nutrient use and metabolism
What is the purpose of the cardiovascular system?
*blood vessels transport blood to carry oxygen, carbon dioxide, nutrients and wastes
*heart pumps blood
What is the purpose of the lymphatic system?
*picks up fluid leaked from blood vessels and returns blood
*disposes of debris in the lymphatic system
*houses white blood cells involved in immunity
*causes the immune response to attack against foreign substances within the body.
What is the purpose of the respiratory system
*keeps blood constantly supplied with oxygen
* removes carbon dioxide
* exchanges gases through the walls of the air sacs of the lungs
What is the purpose of the digestive system?
*breaks down food into absorbable units that enter the blood for distribution to body cells
*indigestible foodstuffs are eliminated as feces
What is the purpose of the urinary system?
*Eliminates nitrogenous wastes from the body
* Regulates water, electrolyte and acid-base balance of the blood.
What is the purpose of the male & reproduction systems?
*to produce offspring
* ducts and glands aid in the delivery of sperm to to the female reproductive tract
* Ovaries produce eggs and female sex hormones
* Mammary glands of female breasts produce milk to nourish the newborn
What is the negative feedback mechanism?
output shuts off the original effect of the stimulus or reduces its intensity.
What are positive feedback mechanisms?