The Nervous System of Animals

What do animals use to respond to their internal and external environment?

Nervous system

Behaviors can be an _________ _________ to something or __________ over _________ periods of time

Immediate reaction to something, or gradual over long periods of time

Are all nervous systems the same?

no

How are all nervous systems similar?

They all function similarly to coordinate the body to perform a behavior

What can the nervous system be thought of as ?

The control center of the body

How many animals lack a nervous system?

A few amount of animals, like sponges, and specific species of aquatic worms

Most animals that have a nervous system have what?>

Central and peripheral nervous system

What is the CNS often nicknamed?

“Brain and spine area”

Where is the peripheral nervous system found?

Throughout the body

What are neurons?

Indviual cells that make up the nervous system and are responsible for transmission of electrical impulses

What mediates electric impulses?

Neurotransmitters

What are neurotransmitters?

Molecules released by neurons which transmit electric impulses throughout the body

What do collections of neurons extending from CNS form?

Nerves

The endsof neurons form _______-like structures

Fiber

What are the fiber-like structures that the end of neurons form covered in?

A layer of connective tissue usually found in the PNS

How fast do neurons transmit information?

Milliseconds

Neurons range from what size to what size?

Milliseconds to meters

The length of neuropns depends on what?

Species and where in the body they are found

How are behaviors coordinated within the CNS?

Neurons communicate with one another to coordinate behaviors

Compared to the connected neurons in the PNS what is different about communicating neurons in the CNS?

They aren’;t physically connected or surrounded with connective tissue

How do CNS neurons communicate?

They project specific chemical cues that attract or repel neurons in order to strengthen or diminish signals

Do neurons in the CNS regrow?

Generally no, but some exceptions

Animals are born with how many neurons?>

Almost all their neurons

WHat happens to neurons as the animal grows?

Strength and speed of the connections adapt to improve the animal’s ability to survive its environment

What types of nerves can regrow or modify?

Nerves in the PNS, in order to continue to send sensation to the CNS

What happens if nerves are severed>?

Sensory info from specific muscles or body parts can be prevented fromm going to the brain or vice versa, leading to a lack of sensation or movement

DO nerves of neurons transmit sensory information?

Nerves

In the nerves neuron relationship what do neurons do?

They convert messages from the nerves (sensory info) into perceived information

While sometimes all animals of a species have the same # of neurons and nerves, what is different between them?

The strength and speed at which the nerves transmit signals can vary

What 2 factors have significant influence on the mechanisms that produce behavior?

Environment and development

What is sensation?

The physical detection of stimuli

An animal touching or smelling something is an example of what?

Sensation

Sensations come from what?

Nerves and organs within the body

Are all animals capable of the same forms of sensations?

No

Toothed whales are similar to what 2 animals in the way they smell?

Orcas and dolphins

How do orcas smell?

Without nerves

List 3 animals capable of smelling without nerves

Orcas, dolphins, tootled whales

Which animal is known no navigate mainly through smell?

Sharks

The range of what an animal is capable of sensing is dependent on what?

The species

Humans can hear sounds at the same frequency as what other animal ?

Mice

What additional hearing ability do mice have that humans don't have?

Sense sounds at ultrasonic frequencies that are too loud for humans to hear

Which of the following animals has the simplest nervous system?

Hydra, Sea star, flatworm, bee, octopus, human

Hydra

What is different between a sea stars nervous system and a hydra?

The sea stars have a more centralized location in the middle of the body

What is similar between flatworms and bees nervous system?

They both don't have spines but have central clusters of nerves

What are the central clusters of nerves in flatworms and bees called?

Ganglia

The ganglia in bees and flatworms work similar to what in a human?

The CNS

What animal has the most complex nervous system between all invertebraes?

Octopus

What advantage do vertebraes have to invertebraes in regards to nervous systems?

They have bones to protect their PNS and CNS

What is the phylum of a hydra?

Cnidarians

What is the phylum of a sea star?

Echninoderm

What is the phylum of a bee?

Arthropod

What is the phylum of an octopus?

Mollusk

What flatworm is depicted in Figure 17 of the USAD academic decathlon science guide?

Planarian

What is the flatworm depicted in the USAD science guide known for in regards to its nervous system?

They don't havve spines but have ganglia that work like a CNS

What parts make up the sea stars nervous system? Where are they located?

Nerve ring and radial nerves; Nerve ring is in the center of the sea star and the radial nerves go along each of the arms of the sea star

The hydra’s nervous system is made up of what?

Simple nerve nets

The Nervous system of the Planarian is made up of what parts? Where are the parts located?

Eyespot, central Ganglia, Nerve Cords, and Transverse Nerve; Eyespot is at the top alongside the Central Ganglia, while the nerve cords and run along the length of the worm and the transverse nerves cut across the width of the nerve

What parts make up the nervous system of the bee? Where are they located?

Central ganglia and segmental ganglia; the central ganglia is in the head while the segmental ganglia runs alongside the bottom of its belly

What parts make up the Octopus’ nervous systeM? Where are they located?

Nerves, Brain, Eye, ganglia; the eye and brain are alongside each other in the head while its ganglia is also found in its head alongside lots of nerves. Nerves are also found in its tentacles

The capacity of an animals sensation is unique to what?

Different species

The anatomy for species capacity for sensations has occured as a result of what?

Evolution to help support a species survival

Do sensory abilities vary within a species?

Yes

How do differences in sensory capabilities in a species come to be?

Random mutations or genetic heritability

What are the examples within humans where a mutation caused sensory changes?

Tetrachromats

What are tetrachromats?

Humans that have additional sensory nerves that can detect additional colors

Sensation causes what?

Imemdiete responses to stimuli

What is necessary for an animal to learn and remember how and when to behave?

Perception

What is perception?

The process of converting sensation fromm different cells in the body to interpret and react to the environment by expressing behavior

Sensation is the ____________ record of information while perception is based on _____________ __________ learning that translates the sensation into a behavior

Physical;Memory and learning

What are the specialized neurons in an animals eyes called?

Rods and Cones

How is visual stimuli information transmitted to the brain region?

Nerve Fibers

Does the Brain use one source to build a picture of the environment?

No multiplesources.

Light hitting the eye and skin detecting warm temperatures are what?

Sensations

When lots of light hits the eye and the skin detects warm temperatures what is the consequent perception?

That you are outside somehwere sunny and hot

What happens after repeated exposure to the sensations and consequent perception of being outside?

The connections between the neurons in the brain strengthen and allow for a faster response to the stimuli of beingoutside.

Is perception objective or subjective?

Subjective

What is perception based on>?

Combination of experiences, current emotions, and the types of sensory neurons in the animal

Animals of the same species are capab;le of _________ the same info

Perceiving

How do animals of the same species differ when it comes to perception?

Their behavioral responses to the perceptions may differ

Perception is unique to every _________

individua

Humans can see color as long as what?

They have the physical structures to do so

What happens when the information of color is combined with other sensory info from the brain and past experiences?

Humans perceive the same colors different ways.

What types of animals possess the most complex nervous systems?

Vertebrae animals

When did the vertebrae nervous system evolve?

500 million years ago

The vertebrae nervous system evolved from what other animals nervous systems?

Worms and insects and other simplistic nervous system animals

What is a spinal column?

A series of bones along the animal’s back

What did the spinal column evolve for?

To support a more complicated and intricate system of nerves

What does the spinal column do?

Protect the nerves and neurons and provide sutrctural support to the rest of the body’;s bones

What is the bundle of nerves inside the spinal column colled?

Spinal cord

What does the spinal cord do?

Trnasmit sensory information from the body t the brain and motor commands from the brain to the muscles

The spinal cord is also responsible for ________ behaviors and controls ____________ and ____________ movements in the body

Reflexive; voluntary and involuntary

What 2 parts make up the vertebrae nervous system?

CNS and PNS

What is the PNS broken down into?

The autonomic and somatic nervous systems

The CNS is to what as the PNS is to what?

The control network; communication network

Can the PNs make its own decisions?

Yes, especially In order to quickly respond to danger but it relies on feedback from CNS

What does the PNS encompass?

All the nerves and neurons outside of the brain and spinal cord

Peripheral nerves can only produce what behaviors?

Immediate reflexive or involuntary behaviors

While the PNS needs the brain for complex behavior, what is the CNS’s relationship with behavior?

It needs the PNS for all behavior

What are the 2 main functions of the somatic nervous system?

Receive sensory input and t control movement

Sensory input includes what?

The 5 serves, sounds, smells, tastes, touch and sight