structural organization of the human body Flashcards
name the structural organisation of the body in order
chemical level, cellular level, tissue level, organ level, organ system and organism
describe Chemical level
- simplest level
- atoms combined to make molecules, which associate to for organelles that form part of cells.
- atoms: nucleus, electron, proton and neutron
describe cellular level
- smallest structural unit of living things
- vary in size and shape to reflect their function
- cells in complex organisms such as humans form tissues
- made up of molecules
describe tissue level
- groups of similar cells that share a similar function
- 4 Basic tissue types: epithelial, muscle, connective tissue and nervous tissue
describe organ level
discrete structure composed of at least 2 tissue types that performs a specific function
describe organ system
- organs that work together to accomplish a common purpose
- highest level of organization
e.g. - respiratory system (lungs, diaphragm, bronchial tree, trachea)
- digestive system (esophagus, stomach, liver, pancreas, intestines)
- renal system (kidneys, ureter, bladder)
- nervous system (brain, spinal cord, nerves)
what does the organized system do
- organ systems work co-operatively to promote the well-being of the entire body.
- every organism has to separate its internal environment from its external environment.
Name the 11 organ systems
integumentary system, skeletal system, muscular system, digestive system, lymphatic system, urinary system, nervous system, cardiovascular system, endocrine system, respiratory system and reproductive system.
What are the functional characteristics of the integumentary system
- external body covering
- protection of deeper tissues from injury
- sensory receptors (pain, pressure, texture)
- temperature regulation (sweat, blood circulation)
- synthesizes vitamin D and houses cutaneous (pain, pressure) receptors and sweat and oil glands.
- cell fluid maintenance
- detection of stimuli
- includes: epidermis, dermis, hypodermis, associated glands, hair and nails.
What are the functional characteristics of the skeletal system
- supports and protect body organs
- provides muscle framework for movement
- formation of blood cells in bones
- storage of minerals
- consists of bones, cartilage, ligaments and tendons
What are the functional characteristics of the muscular system
- movement of body or parts of
- heat production
- allows manipulation of the environment, locomotion and facial expression
- composed of muscle fibers
What are the functional characteristics of the digestive system
- breaks food down into smaller units for distribution by blood to body cells (metabolism)
-eliminates wastes via excretion (indigestible foodstuffs, dead re blood cells) - includes mouth, esophagus, stomach, small intestine, large intestine, liver, pancreas, gallbladder and anus.
What are the functional characteristics of the lymphatic system
- recovers fluid that leaks from blood vessels into tissues
- disposes of cellular debris
- houses white blood cells, involved in immunity
- the immune response mounts the attack against foreign substances within the body
- include bone marrow
What are the functional characteristics of the urinary system
- eliminates nitrogenous wastes from body
- regulates water, electrolyte and acid-base balance in blood
- includes renal pelvis, kidneys, ureters, bladder and urethra
What are the functional characteristics of the nervous system
- body control system
- responds to internal and external changes by activating appropriate muscles and glands
- includes brain, spinal cord and a complex network of nerves
