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HUMAN BODY Part III Name: __________________________Period: _______

The Nervous System

Functions

•To receive _____________________ about what is happening both _______________

and _______________ your body

•To direct the ___________ in which your body _______________ to this information

•To help maintain _______________

Responding to Information

•_______________ – any _______________ or signal in the environment that can make

an organism _______________

•_______________ – what your body does in _______________ to a _______________

Maintaining Homeostasis

•This system _______________ the body to _______________ appropriately to the

information it _______________

–Ex. You are hungry so your body tells you it’s time to _______________

The Neuron

•They are the _______________ that carry information through your _______________

system (aka _______________ cells)

•Nerve _______________ are the _______________ that a neuron carries

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Structure of a Neuron

•Has a large cell body that contains the _______________, threadlike extensions called

_______________, and an _______________

–Dendrites – carry impulses DOWN & _______________ the cell body

–Axon – carries impulses _______________ from the cell body

–Nerve – a _______________ of nerve fibers

Kinds of Neurons

•There are three kinds of neurons found in the body

–1. _______________ neurons – pick up _______________ from the internal or

external environment and _______________ to a nerve _______________

–2. _______________ –_______________ nerve impulses from one

_______________ to another

–3. _______________ neurons – sends an _______________ to a _______________

or gland, and they _______________ in response

How a nerve impulse travels…

•1. _______________ neuron _______________ the stimuli from environment

•2. _______________ in brain _______________ the impulses and makes you

_______________ what is going on

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•3. _______________ neuron carries the impulses to the _______________ and the

muscles carry out the _______________

Synapses

•The tiny _______________ between each _______________ and the next

_______________

•** For a nerve impulse to be carried along, it must _______________ the synapse

between the axon and the next structure. The axon tip releases _______________ that

help the impulse cross the synapse **

Divisions of the Nervous System

•1. __________________________________________________________ (CNS)

–The _______________ and _______________ _______________

•2. __________________________________________________________ (PNS)

–Contains all of the _______________ located _______________ of the ________

CNS

•The ____________________________________ of the body

•There are three main regions of the brain that receive and process information

–_______________ – Interprets input from _______________

–_______________ – coordinates actions of your _______________

–_______________ – controls body’s _______________ actions

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Spinal Cord

•This is the _______________ between your _______________ and the

_______________

PNS

•A network of nerves that _______________ out from the CNS and _______________ it

to the rest of your body

•Both ____________________________ and ____________________________actions

•Can be divided into two groups: _______________ and __________________Systems

Somatic Nervous System

•Control _______________ actions such as using a fork or tying your shoes

Autonomic Nervous System

•Controls _______________ actions

–For example: regulates the contractions in the smooth muscles

Reflexes

•An _______________ response that occurs _______________ and _______________

conscious control (you don’t have to think about it!)

•Help to _______________ the body

Sample Reflex Action

•1. Touch a sharp object. As you pull your hand away, _______________ impulses

travel to your _______________. You feel the pain.

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•2. Nerve impulses return to _______________ neurons in your hand and you pull your

hand away

•3. Nerve impulses travel to your _____________________________

•4. _______________ neurons in your fingertip _______________ a pain stimulus

•5. Ouch!

Nervous system injuries

•______________________________– a _______________ injury of the brain

•Spinal Cord injuries –_______________ become _______________ and nerve

impulses _______________ pass through them

5 Senses and their organs

•1.

•2.

•3.

•4.

•5.

Endocrine System

Characteristics

•Produces _______________ that control the body’s daily _______________ as well as

long term changes such as _______________ and _______________

•Made up of _______________ that produce the chemicals that control body

_______________

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Endocrine Glands

•Produce and release their chemical products directly into the ____________________

and the _______________ carries the _______________ throughout the ___________

–Example chemical is a _______________ (****they turn on, turn off, speed up or slow

down the activities of different _______________ and _______________ ******)

Hormones

•Hormones only interact with certain _______________ cells that _______________ the

hormone’s chemical structure

Endocrine Glands

•Hypothalamus- the link between the _______________ and _______________

systems

•Pituitary- regulates _______________ and ____________________________

•Thyroid- releases _______________ from the cells

•Parathyroid

•Adrenal

•Thymus

•Pancreas

•Ovaries (_______________)

•Testes (_______________)

Reproductive System

Sexual Reproduction

•Involves the production of _______________ by the female and _______________ by

the male, which join together during _______________

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Male Reproductive System

•Specialized to produce _______________ and the hormone _______________

•Structures include the _______________, _______________ and _______________

–Testes produce sperm inside of coiled _______________

–_______________ also produce testosterone which is a hormone that controls the

_______________ characteristics of men

Sperm Production

•The testes are located in an ______________ pouch of skin called the _____________

–The external location keeps the testes about _______________ lower than the usual

body temperature

–This is important because _______________ need the slightly cooler conditions to

develop _______________

Path of Sperm Cells

•Sperm _______________ in the _______________ and mix with _______________

produced by nearby glands. This mixture of fluids is known as _______________.

•Semen leaves the body through the _______________ which is a tube in the

_______________

Female Reproductive System

•Role is to produce _______________ and to nourish a developing _______________

until birth

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•Organs include: _______________, ___________________________________,

_______________, and _______________

–Ovaries produce _______________

–Ovaries produce _______________ that triggers the development of

_______________ characteristics

Path of the Egg Cell

•Each ovary is located near a _______________ tube which is a passageway for eggs

as they go _______________ the _______________ to the _______________

•The uterus is a _______________ _______________ organ

•The egg then enters the _______________ which is a muscular passageway that leads

to the _______________ of the body

Menstrual Cycle

•A _______________ cycle of changes

•During this cycle, an _______________ develops in an _______________. At the

same time, the uterus _______________ for the arrival of an _______________

Stages of the Menstrual Cycle

•1. Egg starts to _______________ in an _______________

•2. _______________ of _______________ begins to thicken

•3. _______________ egg is released from the _______________ into a

_____________________________________________

•4. If _________ fertilized, the extra _______________ and _______________ pass out

of the body through the _______________