Ch 5 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
