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 1
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 2
•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. 4
•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 _______________ 5
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 _______________ 6
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 _______________ 8