Inquiry Into Biology Chapters 11 & 12

Front 1

Neurons

Back 1

The basic structural and functional units of the nervous system.

Specialized to respond to physical and chemical stimuli, to conduct electrochemical signals and to release chemicals that regulate various body functions

Front 2

Peripheral Nervous System (PNS)

Back 2

The nerves that carry sensory messages to the central nervous system and nerves that send information from the CNS to the muscles and glands

Front 3

Central Nervous System

Back 3

Consists of the brain and spinal cord. Integrates and processes information sent by nerves.

Front 4

Nervous system

Back 4

The brain and spinal cord, the nerves that emerge from them to the rest of the body.

Front 5

Homeostasis

Back 5

The state of relative stability within the body

Front 6

Glial Cells

Back 6

These out number neurons 10/1

Are about 1/2 the volume of the nervous system

Nourish the neurons

remove waste

defend against infection

provide supporting framework

Front 7

Nerves

Back 7

Are the individual neurons organized into tissues called nerves

Front 8

reflex arc

Back 8

-Are simple connections of neurons that explain reflexive behaviors

-Involuntary responses to certain stimuli called reflexes

-create rapid reaction in times of danger

Front 9

Dendrites

Back 9

Are short branching terminals that receive nerve impulses from other neurons or sensory receptors and relay the impulse to the cell body

Front 10

Cell Body

Back 10

-Contains the nucleus and is the site of the cells metabolic reactions

-processes info from the dendrite

-if the input received is large enough, the cell body relays it to the axons

Front 11

Axon

Back 11

-A neuron typically has one

-Conducts impulses away from the cell body

-range from 1mm to 1m in length

Front 12

Membrane Potential

Back 12

The charge separation across the membrane is a form of potential energy.

Front 13

Schwann Cells

Back 13

- A type of glial cell

-form myelin by wrapping themselves around the axon

Front 14

Myelin sheath

Back 14

- a fatty, insulating layer enclosing some axons

-gives axons glistening white appearance

-protects myelinated neurons and speeds the rate of nerve impulse transmission

Front 15

Resting Membrane Potential

Back 15

The potential difference across the membrane in a resting neuron

Front 16

Polarization

Back 16

The process of generating a resting membrane potential of -70mV

Front 17

Sodium-Potassium Exchange Pump

Back 17

-Uses the energy of ATP to transport sodium ions out of the cells and potassium ions into the cell.

-Exchanges 3 sodium ions for 2 potassium ions

Front 18

Action Potential

Back 18

-In an axon, the changein charge that occurs when the gates of K+ (potassium) channels close and the gates of the Na+ (sodium) channels open after a wave of depolarization is triggered

-considered an all or none event

Front 19

Threshhold potential

Back 19

In a neuronal membrane the minimum change in the membrane potential required to generate an action potential

-usually -55mV

Front 20

Nodes of Ranvier

Back 20

A gap in the myelin sheath insulating the axon of a nyelinated nerve cell; the membrane of an axon exposed and action potentials occur only at these nodes;

-Nerve impulses jump from one node to the next. (Node rhymes with Toad, that just from one pad to another)

Front 21

Depolarization

Back 21

Is the transmembrane potental is reduced to less than the resting potential of -70mV

Front 22

Cholinesterase

Back 22

An enzyme that breaks down the neurotransmitter acetylcholine in synapes

Front 23

Acetylcholine

Back 23

The primary neurotansmitter of both the somatic and parasympathetic nervous systems

Front 24

Neurotransmitters

Back 24

A chemical messenger secreted by neurons to carry a neural signal from one neuron to another; or form a neuron to an effector, such as gland or muscle fiber.

Front 25

neuromuscular junction

Back 25

The synapes between a motor neuron and a muscle cell

Front 26

Synapes

Back 26

A junction between two neurons or between a neuron and an effector (muscle or gland)

Front 27

Refractory period

Back 27

The brief time (a few milli seconds) between triggering of an impulse along an axon and the axons readiness for the next impulse; during this time the axon cannot transmit an impulse

Front 28

Repolarization

Back 28

The return of a nerve to it's resting potential following depolarization

Front 29

Medulla Oblongata

Back 29

The part of the Hindbrain that is attached to the spinal cord at the base of the brain stem;

controls automatic, involuntary responses such as heart rate, constriction and dilation of blood vessels to control blood pressure and the rate and depth of breathing swallowing and coughing

Front 30

Pons

Back 30

Part of the Hindbrain above and in front of the medulla oblongata in the brain stem

-relays center between the neurons between the right and left half's of the cerebrum, the cerebellum, and the rest of the brain

Front 31

Cerebellum

Back 31

The part of the hindbrain involved in unconscious coordination of posture, reflexes and body movement as well as fine, voluntary motor skills

Front 32

Meninges

Back 32

3 layers of tough, elastic tissue within the skull and spine which directly enclose the brain and spinal cord

Front 33

White matter

Back 33

The part of the nervous system that make up the tracts of myelinated nerve fibers, whitish in color; forms the inner region of some areas of the brain, and the outer area of the spinal cord.

Front 34

Grey Matter

Back 34

The part of the nervous system that contains mostly cell bodies, dendrites and short, unmyelinated nerve fibers; brownish grey in color, forms the outer areas of the brain and the H shaped core of the spinal cord.

Front 35

Fovea Centralis

Back 35

A concentration of cones on the retina; located directly behind the lens

Front 36

Hair Cells

Back 36

The mechanoreceptor attached to the basilar membrane in the organ or Corti within the inner ear

Front 37

Hyperopia

Back 37

-Far sightedness

-Caused by the weak ciliary muscles or an eyeball that is too short

Front 38

Inner ear

Back 38

One third of the ear

- Consists of semicircular canals, vestibule and cochlea

Front 39

Membrane Potential

Back 39

An electrical charge separation across a cell membrane; a form of potential energy

Front 40

Middle Ear

Back 40

One third of the ear

-Begins at the tympanum(drum) and ends at the 2 small openings in the wall of the inner ear called the round window and the oval window

Front 41

Myopia

Back 41

Near sightedness

-Ciliary muscles are too strong or an eyeball that is too long

Front 42

Organ of Corti

Back 42

Ear

-Found within the Cochlea of inner ear

-Contains hair cells that detect vibrations in the inner ear and transmit information to auditory nerves

Front 43

Otoliths

Back 43

A calcium carbonate granule associated with sensory receptors for detecting movement in the head and vertebrates

-located in the utricle and saccule in the vestibule of the inner ear.

Front 44

Olfactory Bulb

Back 44

The forebrain where sensory nerve fibers from the nose terminate and transmit Olfactory information to the other areas of the brain

Front 45

Olfactory cells

Back 45

A chemoreceptor for the sense of smell; lines the upper nasal cavity

Front 46

Ossicles

Back 46

The 3 small bones between the tympanum and the oval windows of the middle ear;

-transmit sound waves from the ear drum to the inner ear

Front 47

Tectorial membrane

Back 47

One of two parallel membranes that comprise the organ of corti in the inner ear;

-during the transmission of the sound waves, the basilar membrane vibrates, causing the sensory hairs to flec against the tectorial membrane

Front 48

Utricle

Back 48

The sac like cavity in the vestibule of the inner ear; Contains receptors for gravitational equilibrium

Front 49

Tympanum

Back 49

A round elastic structure within the middle ear that vibrates in response to sound waves;

eardrum

Front 50

TasteBuds

Back 50

Receptor in the bumps on the tongue

Front 51

Sound wave

Back 51

-A small fluctuation in air pressure resulting from sound

-Causes particles to move; the auditory system detect these movements and the brain perceives them as sound.

Front 52

Semi Circular Canals

Back 52

One third of Inner ear components

- 3 fluid filled loops, arranged in 3 different planes.

-contains mechanical receptors that detect head and body rotation

Front 53

Saccule

Back 53

A sac like cavity in the vestibule of the inner ear; contains sensory receptors for gravitational equilibrium

Front 54

Rotational Equalibrium

Back 54

Balance required while rotating the head and body

Front 55

Pinna

Back 55

The outside flap of the ear, made of skin and cartilage

-shaped in a way that enhances sound vibrations and focuses them into the ear.

Front 56

Proprioceptors

Back 56

Mechanoreceptors found in the muscles, tendons and joints;

-senses the body's position and movement to send information about body position tot he brain

Front 57

Outer ear

Back 57

One of three separate segments of the ear

-Consists of the pinna and the auditory canal

Front 58

Oval Window

Back 58

A membrane covered opening in the wall if the inner wall; receives vibrations from the stapes

Front 59

Eustatian Tube

Back 59

The bony passage extending from the middle ear to the throat;

-plays a role in equalizing air pressure on both sides of the eardrum

Front 60

Color Blindness

Back 60

The inability to distinguish between or recognize some colors.

-inherited; more often in men

-Caused by a lack of potential cones, typically red and green

Front 61

Cataracts

Back 61

Cloudy or opaque, grey and/or white area on the lens.

- caused by degeneration of the protein structure of the lens

-prevents the passage of light

Front 62

Cochlea

Back 62

One third of the inner ear

-involved in hearing

-the mechanical energy of the sound is converted into electrochemical impulses that are transmitted to the brain.

Front 63

Basilar Membrane

Back 63

One of two parallel membranes that comprise the organ of Corti in the inner ear.

-Lies along the base of the organ of corti attached to the mechanical receptors known as haircells

Front 64

Blind spot

Back 64

Region of the retina lacking photoreceptors (rods or cones) where the optic nerve leaves the eye;

-is incapable of detecting light

Front 65

Auditory Canal

Back 65

The tube that conducts sound waves from the outer ear to the tympanium(ear drum) of the middle ear; amplifies sound waves, effectively making sound louder

Front 66

Accomodation

Back 66

In the eye, an adjustment made by the ciliary muscles to shape the lens to focus objects at varying distances

Front 67

Astigmatism

Back 67

The uneven curvature of part of the cornea or lens that results in uneven focus and therefore blurry vison

Front 68

Lens

Back 68

A clear flexible part of the ey that focuses images on the retina

Front 69

Vitreous humor

Back 69

Clear-jelly like fluid inside the posterior chamber of the eye;

-helps to maintain the shape of the eyeball and support the surrounding cells

Front 70

Glaucoma

Back 70

When ducts that drain aqueous humor are blocked.

-results in pressure rupture of the blood vessels

-Cell death due to lack of oxygen and nutrients

-Can lead to blindness

Front 71

Aqueous Humor

Back 71

The clear watery fluid in the anterior chamber of the eye.

-maintains shape of the cornea

-provides oxygen and nutrients for surrounding cells including lens and cornea

Front 72

Optic Nerve

Back 72

A nerve that carries messages from photoreceptors in the retina to the brain

Front 73

Cones

Back 73

A type of photoreceptor in the eye that is sensitive to different colors

Front 74

Rods

Back 74

A type of photo receptor in the eye that is more sensitive to light intensity(brightness) than is a cone.

-unable to distinguish color

Front 75

Retina

Back 75

The inner most layer of the eye, containing the photo receptors rods and cones

Front 76

Adaptation

Back 76

A structure, behavior or physiological process that helps an organism survive and reproduce in a particular environment.

Pupil dialation

Front 77

Pupil

Back 77

Aperture in the middle of the iris, the size of which can be adjusted to control the amount of light entering the eye.

Front 78

Iris

Back 78

A doughnut shaped, colored muscle formed from the choroid at the front of the eye; adjusts the central dark pupil to regulate the amount of light that enters the eye

Front 79

Choroid

Back 79

-Vascular membrane of the eye that lies between the retina and the sclera.

-Absorbs stray light rays that are not detected but the photo receptor in the retina

Front 80

Cornea

Back 80

The transparent part of the Sclera at the front of the eye, through which light enters

Front 81

Sclera

Back 81

The white, tough, fibrous protective layer that gives the eye it's shape

Front 82

Mechanoreceptor

Back 82

Sensory receptor that responds the mechanical stimuli, such as that from

-pressure

-sound waves

-gravity

Front 83

Chemoreceptors

Back 83

Sensory receptor that is sensitive to chemical stimuli

-such as taste, smell and blood pH

Front 84

Phtotreceptors

Back 84

Sensory receptor that responds to light stimuli and allows us to sense different levels of light and shades of color.

Front 85

Sensory Adaptation

Back 85

The filtering by the brain of redundant, insignificant sensory information.

Front 86

Preception

Back 86

Interpretation of sensory information by the cerebral cortex

Front 87

Sensation

Back 87

Receiving and processing by the brain of neural impulses from receptors.

ir. skin detects heat, processes information and makes the area warm.

Front 88

Sensory receptors

Back 88

-Cell or group of cells scattered throughout the body that works continually to receive information about the bodies external conditions throughout sensory and internal conditions (glucose,pH, BP and then initiates neural impulses n response)

Front 89

Parasympathetic Nervous system

Back 89

-Autonomic system that regulates involuntary processes in the body.

-works in opposition to the sympathetic nervous system.

-typically activated when the body is at rest.

Front 90

norepinephrine

Back 90

Neurotransmitter released by sympathetic neurons of the autonomic

-Produces excitetory effect on muscles

Front 91

Sympathetic Nervous System

Back 91

-Division autonomic

-regulates involuntary processes.

-works in opposition to parasympathetic.

-Typically activated in stress related situations.

Front 92

Autonomic System

Back 92

In Vertebrates, the division of Peripheral Nervous System that is under involuntary control; regulates glandular secretions and the function of smooth and cardiac muscles

Front 93

Somatic System

Back 93

-IN Vertebrates, division of the PNS that controls voluntary movement of skeletal muscle; conducts signals from the CNS to the skeletal muscles and signals from the sensory receptors in the body of the CNS.

Front 94

Wernickes Area

Back 94

One of two sides of the cerebral cortex

- stores the information involved in language comprehension and the ability to letter words.

-Words make sense, damage results in inability to understand, but mechanics still work.

Front 95

Broca's Area

Back 95

One of two sides of the cerebral cortex

-Coordinates the muscles for speaking ad translates thought into speech.

Front 96

Frontal Lobes

Back 96

-Integrates information from other parts of the brain; and controls reasoning, critical thinking, memory and personally.

Brocas area- language use, motor areas control various aspects of precise voluntary movement.

Front 97

Parietal Lobes

Back 97

1 of 4 lobes- Receives and process sensory information from the skin, and helps process info. about the bodies position and orientation.

Front 98

Temporal Lobes

Back 98

-Shapes and processing of visual information

-Main function is auditory reception

-Understanding speech and retrieving visual and verbal memories.

Front 99

Occipital Lobes

Back 99

1 of 4 lobes

-receives and analyzes visual information

-Is needed for recognition of what is being seen.

Front 100

Corpus Callosum

Back 100

-White matter that joins the two cerebral hemispheres of cerebrum.

-Sends messages from one side to another

-Telling each half of the brain what the other is doing.

Front 101

Cerebral Cortex

Back 101

-The thin outer covering of grey matter

-responsible for language, memory, personality, conscious thought and others associated with thinking and feeling.

Front 102

Cerebrospinal fluid

Back 102

-Dense clear fluid

-Acts as a shock absorber to cushion the brain

-Found in ventricles of brain, central canal of the spinal cord.

-Transport hormones, white blood cells and nutrients across to the cells of the brain and spinal cord.

Front 103

Blood-Brain Barrier

Back 103

-Protective barrier formed by glial cells and blood vessels that separates the blood from the CNS

-Selectively controls the entrance of substances into the brain from the blood.

Front 104

Cerebrum

Back 104

-The largest part of the brain

-Right hemisphere and left hemisphere

-Center for intellect, memory, consciousness and language.

-Interprets and controls the response to sensory information.

Front 105

Hypothalamus

Back 105

The region of the forebrain just below the cerebral hemispheres, under the thalamus; a center f the autonomic nervous system responsible for the integration and correlation of many neural and endocrine functions; helps to regulate the bodies internal environment as well as behavior, pituitary by releasing hormones.

Front 106

Thalamus

Back 106

-The sensory relay center at the base of the forebrain that governs the flow of information from all other parts of the nervous system, mainly between the fore and hindbrain and between the areas of the sensory system (except smell) and cerebellum.

Front 107

Midbrain

Back 107

Part of the brain found above the pons in the brain stem.

-relays visual and auditory information between the areas of the hindbrain and the forebrain and plays an important role in eye movement and control of skeletal muscles.