science biology (ecosystems & body systems) Flashcards
what is cellular respiration?
oxygen + glucose –> carbon dioxide + water
what are the different body systems?
-digestive
-respiratory
-circulatory
-excretory
what is the major organ for each body system?
digestive : stomach
respiratory : lungs
circulatory : heart
excretory: kidneys
food contains ________________?
complex nutrients
how is food broken down into simple substances?
through chemical digestion
carbohydrates –> ______________
glucose
how are these simple substances absorbed?
through the walls of the small interstine
where are the simple substances taken (digestive)?
they are taken to the capillieres and into the blood stream (through diffusion)
what is diffusion?
the random movement of particles from an area of high concentration to an area of low concentration until equilibrium.
how does the respitory system work?
Air diffuses in / out of the respiratory system through a process of
ventilation (inhalation/exhalation)
what happens during gas exchage?
-Oxygen diffuses from air in the alveolus
into the blood capillaries
-Carbon dioxide diffuses from the blood capillaries into air in the
alveolus
how does the circulatory system work?
Blood is pumped by the heart throughout the circulatory system in a
network of arteries and veins, and tiny vessels called capillaries.
what does blood in the circulatory system contain?
The blood contains gases, nutrients and wastes which will be
supplied and removed by the other systems.
what is urea?
Urea is a waste product from protein metabolism (breakdown) in the
liver
what does the circulatory system supply to cells?
-oxygen gas
-glucose & other nutrients
what does the circulatory system remove from cells?
-carbon dioxide
-waste and urea
what is homeostasis?
The maintenance of a constant internal environment
what are some conditions of homeostasis?
water regulation
* temperature regulation
* gas concentrations
what is the nervous system?
The nervous system is a network of nerves which communicates between the brain and the other systems of the body.
what is the cns?
cns is the central nervous system which includes the brain and the spine.
what is the pns?
pns is the perpiphial nervous system, which includes nerves all around the body.
what is a stimuli?
Changes in the environment which can be detected by receptor cells
