Nervous and Endocrine System Flashcards
are irritable, and they tend to respond to all changes happening in their internal and external environment
animals
may be brought by changes in terms of the amount of food, water, oxygen, and even waste materials
internal stimuli
Example of external stimuli:
temperature
pH
moisture
light
gravity
pressure
ability to respond to changes occurring within the animal’s body and its external environment
irritability
three principal components of irritability:
reception of stimulus
conduction of signal
response by an effector
three distinct functions of irritability
sensory
integrative
motor
function of irritability that detects changes in internal and external environment
sensory
function that brings sensory information together and make decisions that are acted upon by using motor functions
integrative
functions to responds to stimuli by initiating muscular contraction or glandular secretion
motor
Composed of hydra, jellyfish, sea anemones
cnidarians
have the simplest nervous system organization with a nerve net
cnidarians
cnidarians have this network of nerve cells that are connected to the receptors in the epidermis
protoneurons
which directions does the single impulse travels producing a generalized response or contraction in cnidarians
all direction
Composed of sea stars, sea urchins, sea cucumbers
echinoderms
have a ring-like nervous system, no brain
echinoderms
where the nervous system of echinoderms has ring around with five nerves radiating outward
esophagus
have a linear/bilateral/ladderlike nervous system
flatworms
Have a distinct ganglia or “brain” connected to two main nerve trunks/cords that run posteriorly and laterally to various body parts of the body
flatworms
has a centralized nervous system and has two ventral nerve cords, with a pair of ganglia, afferent and efferent neurons in each body segment
annelids
Centralized nervous system but have larger ganglia and developed sense organs
arthropods
Centralized nervous system with a embryonically with a
single, hollow, dorsal nerve cord
vertebrates
animals that exhibit cephalization
vertebrates
With anteriorly located brain connected to spinal cord and nerves (cranial and spinal nerves)
vertebrates
also called nerve cells and serve as the functional unit of the nervous system
neurons