Science T2 Flashcards
Homeostasis
The maintenance of a constant internal environment
Body systems use _____, _____ and _____ to achieve homeostasis
Receptor (senses new variables) Processing Center (finds what to do about it) Effector (acts on the variable)
Negative Feedback Loop
A type of feedback loop where a new variable is counteracted to try get to an ideal setting
Positive Feedback Loop
A type of feedback loop where a new variable is intensified by a response
Diffusion
The movement of molecules from an area of high concentration to an area of low concentration
Osmosis
A special kind of diffusion that involves the diffusion of water across a cell membrane
Active Transport
The movement of molecules from an area of low concentration to an area of high concentration
Cytosis
An active process in which materials move into or out of the cell enclosed as vesicles
Cell Membrane
A biological membrane that separates the interior of all cells from the outside environment
Passive Process
A way for ions and molecules to go through the cell membrane without using energy
Three types of passive processes are ____, ____ and _____.
Simple diffusion, filtered diffusion, osmosis
Excretion
The removal of wastes produced by metabolism within cells
Elimination
The removal of undigested materials from the body
Kidneys
Organs that filter blood to remove wastes (urine)
Ureter
A tube that transports urine from the kidney to the bladder
Bladder
A organ that is the place for the temporary storage of urine.
How does the bladder get urine out of it?
It contracts to squeeze the urine out
Urethra
A tube that transports urine from the bladder to outside of the body.
The three regions of the kidney are:
- _____
- ____
- _____
- Cortex (Outside)
- Medulla (Middle)
- Pelvis (Inside)
Cortex (Outside)
An area in the kidney where the filtration occurs
Medulla (Middle)
An area in the kidney where useful substances are reabsorbed
Pelvis (Inside)
An area in the kidney where urine collects before travelling down to the bladder (via the ureter)
Hypotonic Solutions
Solutions that have a low concentration (makes cells swell)
Hypertonic Solutions
Solutions that have a high concentration (makes cells shrivel up)
Isotonic Solutions
Solutions that are half liquid, half solute (cells stay the same)
Nervous system
A series of tissues and organs that are the prime communication system within the body
Sensory input
Monitoring stimuli occurring inside and outside the body
Integration
Interpretation of sensory input
Motor output
Response to stimuli by activating effector organs
The sympathetic (speed up) division of nerves
A division of nerves that increases the action of the body e.g. increases heart and breathing rate
The parasympathetic (slow down) division of nerves
A division of nerves that decreases the action of the body e.g. decreases heart and breathing rate
Central Nervous System (CNS)
The main nervous system that is made up of the brain and spinal cord
Peripheral Nervous System (PNS)
A group of nerves that are made up of parts of the nervous system outside the brain and spinal cord
The cell membrane is composed mainly of ___ and ___.
Lipids & proteins
Diffusion only occurs when _____________________.
Diffusion only occurs when there is a difference in concentration between the two areas
Why does osmosis work?
Water molecules are very small and so pass through the cell membrane easily.
Osmosis is a ____ process.
Passive process
Cell Body
A section of the neuron that carries out the essential cell processes that keep the cell alive
Dendrites
Short branched extensions from the cell body that receive impulses from other neurons or receptors
Axon
Single (usually) long cylindrical process extending from cell body that transmits nerve impulse away from cell body
Myelin sheath
Bunches of fat around the axon
Nodes of Ranvier
Gaps in the myelin sheath
Synaptic terminal
A part of the neuron at the end of the axons and dendrites that communicate to other neurons
