Full final

Peripheral Nervous System (PNS)

One of the two major divisions of the nervous system

Central Nervous System (CNS)

One of the two major divisions of the nervous system

Central Nervous System (CNS) structures

Brain and spinal cord

Peripheral Nervous System (PNS) role

Carries messages between the CNS and the rest of the body

Dendrites

Carry messages toward the cell body

Axon

Transmits impulses away from the cell body

Myelin

Insulates and protects the axon; speeds up nerve impulses

Cell Body

Controls the neuron and contains the nucleus

Direction of nerve impulses

Dendrites → Cell Body → Axon

Cerebellum

Regulates muscle movements

Temporal Lobe

Processes hearing, memory, and language

Ventricles

Contain and circulate cerebrospinal fluid

Meninges

Membrane layer absorbs impulses

Sympathetic division

Responsible for fight or flight

Parasympathetic division

Responsible for rest and digest

Reflex arc order

Sensory Receptor → Afferent Neuron → Brain/Spinal Cord → Efferent Neuron → Motor Response

Multiple Sclerosis

Myelin sheath is damaged or destroyed

Importance of myelin

Helps nerve impulses travel quickly and efficiently

encephal/o

Brain

-paresis

Partial paralysis

-mnesia

Memory

Why cerebellum damage affects balance

The cerebellum controls muscle coordination and balance, so damage causes unsteady movements

Cerebrospinal fluid importance

Cushions and protects the brain and spinal cord and transports nutrients

Cornea

The clear front window that refracts light and provides most optical power

Iris

The colored part of the eye that regulates the amount of light entering by changing pupil size

Retina

The light-sensitive inner lining containing rods and cones that convert light into electrical signals

Sclera

The tough white outer layer that protects the eyeball and maintains shape

Lens

A transparent biconvex structure that changes shape to focus light on the retina

Optic Nerve

Carries visual information from the retina to the brain’s occipital lobe

Light pathway through eye

Cornea → Pupil → Lens → Retina → Optic Nerve

-opia

Vision condition

dacry/o

Tears

Hyperopia

Farsightedness

Cataracts

Lens becomes cloudy causing blurred vision and possible blindness

Color Blindness

Deficiency in cone cells causing difficulty distinguishing colors

Myopia

Nearsightedness where light focuses in front of retina causing distant objects to appear blurry

Hyperopia disorder

Farsightedness where light focuses behind retina causing close objects to appear blurry

Importance of cornea

Primary refractive surface that focuses light onto the retina

Optic nerve damage result

Partial or total permanent vision loss even if eye is healthy

Auricle/Pinna

External ear flap that captures and funnels sound waves into the ear canal

Tympanic Membrane

Eardrum that vibrates in response to sound waves

Cochlea

Snail-shaped fluid-filled structure containing hair cells that convert vibrations into nerve impulses

Auditory Nerve

Carries auditory information from the cochlea to the brain

Semicircular Canals

Three fluid-filled loops detecting head rotation and maintaining equilibrium

Sound pathway

Outer Ear → Ear Canal → Tympanic Membrane → Ossicles → Cochlea → Auditory Nerve

Vertigo

Medical term for dizziness

Otology

Study of the ear

Structure that changes vibrations into nerve impulses

Cochlea

Structures maintaining equilibrium

Semicircular canals and vestibule

Why inner ear problems cause dizziness

Fluid or hair cell problems send incorrect movement signals to the brain causing vertigo

Hearing loss from lack of nerve impulse conversion

Cochlea may not function properly

Pupils not adjusting to bright light

Damage to iris

Importance of special senses

Allow organisms to detect environmental dangers and communicate

Endocrine system communication

Uses hormones

Hormones travel through

Blood

Endocrine system works closely with

Nervous system

Pituitary Gland

Produces many hormones that stimulate other hormones

Thyroid Gland

Produces thyroxine that stimulates metabolism

Adrenal Glands

Produce adrenaline

Pancreas

Regulates blood sugar with insulin and glucagon

Homeostasis

Keeping the body in balance and able to carry out cellular processes

Importance of homeostasis

Too much or too little hormone disrupts cellular processes

Insulin

Lowers blood sugar levels

Glucagon

Raises blood sugar levels

Blood glucose after sugary meal

Blood glucose levels increase

Hormone responding to high blood sugar

Insulin

Organ releasing insulin

Pancreas

Fight or flight hormone

Adrenaline

Hormone released during long-term stress

Cortisol

Stress body change

High blood pressure

Stress body change

Shutting down sperm and egg production

ADH function

Tells kidneys to conserve water

Importance of water balance

Regulates blood pressure and homeostasis

Pituitary gland called master gland

Controls release of many other hormones

Why pancreas belongs to endocrine and digestive systems

Secretes hormones in response to digestion

Hyperthyroidism

Overproduction of thyroid hormones increasing metabolism

Diabetes

Pancreas does not release enough insulin

External respiration

Exchange of gases between lungs and blood

Oxygen movement in external respiration

Oxygen moves from bloodstream into tissues

Carbon dioxide movement in external respiration

Carbon dioxide moves from tissues into bloodstream and is exhaled

Oxygen in inhaled air

21%

Oxygen in exhaled air

16%

Alveoli

Air sacs of lungs

Internal respiration

Exchange of gases between blood and body cells

Oxygen movement in internal respiration

Oxygen moves from blood to body cells

Carbon dioxide movement in internal respiration

Carbon dioxide moves from body cells to blood

Why cells need oxygen

To produce ATP through cellular respiration

Internal respiration definition

Exchange of oxygen and carbon dioxide at the cellular level

Mediastinum

Space in the middle of the chest

Bronchi

Two main airways branching from the trachea

Hilum

Entry and exit point for blood vessels, nerves, lymphatic tissue, and bronchi

Lungs

Organs divided into lobes

Singular of bronchi

Bronchus

Larger lung

Right lung

Right lung lobes

3

Left lung lobes

2

Air pathway

Nasal cavity → Pharynx → Larynx → Trachea → Bronchi → Bronchioles → Alveoli

Gas exchange structures

Alveoli and lung capillaries

Conducting structures

Trachea, bronchi, bronchioles

Alveolus/Alveoli

Tiny air sacs where oxygen and carbon dioxide are exchanged