animal structure and function 2 Flashcards
nerve cells
neurons
Name the three major types of neurons, and describe their function.
- sensory neurons - carry messages to the brain and spinal cord from nerve endings
- motor neurons - carry messages away from the brain and spinal cord to the muscles and glands
- interneurons - found in the brain and spinal cord connecting sensory and motor neurons
a change in the internal or external environment that causes a response
stimulus
a reaction to a stimulus
a response
nerve endings that detect stimuli
receptors
muscles and glands that react to motor neurons
effectors
What two systems does the body usually use to respond to stimuli?
- skeletomuscular
2. endocrine (hormones)
a nervous system that looks like a spider web with no collection of nerve cells - What kind of animals have this?
nerve net - cnidarians
a nervous system that looks like a ladder - What kind of animals have this?
nerve cord - flatworms
small clumps of nerve cells that control specific regions of the body
ganglia
ganglia in the head
cerebral ganglia
a larger collection of nerves that allows for complex behaviors including learning
brain
Name the three major parts of a chordate brain
- cerebrum
- cerebellum
- brain stem
the thinking part of the brain responsible for learning and memory
cerebrum
the balance and coordination part of the brain
cerebellum
the part of the brain the connects to the spinal cord and controls involuntary survival processes like breathing and heart rate
brain stem (medulla oblongata)
the part of the brain for vision
optic lobe
the part of the brain for smell
olfactory bulb
the nerve cord that connects the brain to the rest of the body
spinal cord
What happened to the brain through evolution from fish to amphibians to reptiles and mammals?
larger and more complex
detect light without getting an image
ocelli (eyespots)
an eye made of many lenses, good at detecting motion
compound eye
the ability of an animal to produce an image of their surroundings by sound waves bouncing back to them
echolocation
the concentration of nerves and sensory structures in the heads of organisms
cephalization
a water skeleton, fluid held in a body cavity surrounded by muscle
hydrostatic
an external skeleton
exoskeleton
an internal skeleton
endoskeleton
What is the disadvantage of an exoskeleton?
It can’t grow so it must be molted leaving the animal unprotected
What is the advantage of an endoskeleton?
It grows with the organism and doesn’t need to be molted
What is the advantage of a hydrostatic skeleton?
no structures to build - less energy
Give 2 examples of animals with hydrostatic skeletons.
worms, cnidarians
Give an example of an animal with an exoskeleton
arthropods - insects, spiders, crayfish…
Give an example of animals with an endoskeleton.
echinoderms, fish, amphibians, reptiles, birds, mammals