Human Body Systems Flashcards
Homeostasis
Process by which organisms keep internal conditions relatively constant despite changes in the External environment
Negative feedback
Tends to reduce the input signal that caused it and helps to maintain stability in the system in spite of external changes
Positive feedback
Tends to increase the event that caused it gives the system the ability to access new point of equilibrium
Nervous system
Controls and coordinates functions throughout the body in response to internal and external stimuli
Neurons
Cells that transmit impulses from one spot in the body to
Synapse
Location in which a neuron can transfer an impulse to another nerve cell
Neurotransmitter
Chemicals used by a neuron to transmit an impulse across the synapse to another cell
What is found in the central nervous system
Brain and spinal cord
Brain
The place to which impulses flow and it from which impulses originate
Spinal cord
The communication link between the brain and the rest of the body
Peripheral nervous system
Consists of all the nerves and associated cells that are not part of the brain and spinal cord
Somatic nervous system
Regulates activities that are under the conscious control
Autonomic nervous system
Regulate the activities that are automatic or involuntary
Pain receptors
Found everywhere except the brain and respond to chemicals released by damage to cells
Thermoreceptors
Located in the skin core and hypothalamus and detect variations in temperature
Mechanoreceptors
Found in the skin skeletal muscles and inner ear and respond to touch, pressure, stretching of muscle, sound, and motion
Chemoreceptors
Located in the nose and taste buds and respond to chemicals in the
external environment
Photoreceptors
Found in the eye and are sensitive to light
Digestive system
A continuous tubelike passageway that extends from the mouth to the anus
Digestion
Break down food into molecules the body can use
Absorption
Movement of nutrients into the blood carries nutrients to cells throughout the body
What is the passageway of food throughout the body
Mouth, pharynx, esophagus, stomach, small intestine, large intestine
What are the three accessory organs in the digestive system
Pancreas, liver, and gallbladder
Salivary glands
Make saliva, and begin mechanical and chemical digestion
Esophagus
Muscular tube that leads to the stomach
Peristalsis
Wavelike motion of two muscles contracting to push the bolus down the esophagus
Sphincter
Ring of muscle at the base of the soffit guess prevents material from leaving the stomach
Stomach
Produces chime or a semi fluid mass of digested food
Small intestine
Absorbs nutrients and continues chemical digestion
Large intestine
Eliminates waste and absorbs the water, minerals, and vitamins
Pancreas
Secretes enzymes to break down and makes sodium bicarbonate to neutralize acidic time from stomach
Liver
Produces bile
Bile
Emulsifies fat and breaks down large that globules into smaller ones
Gallbladder
Greenspan located beneath lobe of the liver
Respiratory system
A group of organs working together to bring about oxygen and carbon dioxide the environment
Nasal cavity
Lined with hair for filtering and kept moist by mucus secretion
Pharynx
Located at the back of the mouth and is the common passageway for air and food
Larynx
Located at top of trachea made of cartilage pieces that include the Adams apple and voicebox
Trachea
(Wind pipe) Made of session rings of cartilage which provide protection and flexibility
Bronchi
The trachea divides into two branches the left and the right ____
Lungs
Main organ of the respiratory system
Bronchioles
connect to tiny air sacs called Alvioli
Alveoli
Separate gas from the liquid taking out carbon dioxide from the blood and replacing with oxygen
Breathing
Caused by the diaphragm
Circulatory system
Composed of blood heart and blood vessels
What is the path that blood follows
Vena cava, right atrium, right ventricle, pulmonary artery, lungs, pulmonary veins, left atrium, left ventricle, aorta
Septum
Devides left and right
Atrium
Top half of heart accepts blood and pumps to ventricles
Ventricles
Bottom half of the heart pumps blood to lungs or body
Blood vessel
Includes arteries capillaries and veins
Arteries
Carry blood from the heart to the body
Capillaries
Arterioles branch into these they’re so small that sells must pass through in a single file line
Veins
Blood moves from capillaries into these
Excretory system
Confused of the skin lungs and kidneys main purpose is to remove metabolic waste
Kidneys
Main organ of been excretory system to be shaped organs that have blood flowing into them through the renal artery and out them through the renal vein the waste removed from the blood by the kidney is carried out by the ureter to the urinary Bladder
Infection
When your body is successfully invaded by a pathogen
First-line defense
Primary defense against disease causing microorganisms
Nonspecific
General defense protects body against all infections
Second line defense
If pathogens managed to enter the body the ____ kicks in
List the levels of organization from smallest to largest
Cells, tissues, organs, and organ systems
