Chapter 5 Vocab Flashcards
Homeostasis
An organism maintaining a stable constant internal environment (physiological)
Stomata (Stomate)
The opening between two guard cells in the epidermis of a plant leaf through which gases are exchanged with the air
Sensory neurons
Nerve Cells that transmit information from a sense organ to the brain
Physiological response
An automatic change generated by the body of an organism that is triggered by an external or internal stimulus
Motor neurons
A nerve cell that conducts information to muscles or glands
Behavioral response
Actions taken by an organism in response to some stimulus
Reflexes
An involuntary reaction or response to a stimulus
Nervous system
A coordinating mechanism in almost all multicellular organisms that regulates internal body functions and response to external stimuli. In vertebrates, it consists of the brain, spinal cord, nerves, ganglia and receptor/effector organs.
Neurons
A nerve cell (brain, sensory and motor nerves are examples)
Here is a picture of an entire neuron with all of its parts labeled
Hypothalamus
A part of the brain. In humans, it links the nervous system to the endocrine system (which controls hormones and other bodily functions)
Negative feedback
A kind of feedback that creates equilibrium between input and output in a system or process
Positive feedback
A kind of feedback that disturbs or prevents equilibrium between input and output in a system or process. (a response that promotes or increases similar response without regard to equilibrium)
Dendrites
A structure that extends out from a neuron and transmits impulses toward the cell body
Axon
A structure that extends out from a neuron and conducts impulses away from the cell body
Stimulus
A change or signal in the internal or external environment that causes an adjustment or reaction by an organism
Synapse
An open junction between neurons, across which an impulse is transmitted by a chemical messenger called a neurotransmitter
