Health Science study guide

what is a neuron?

the basic structural unit of the nervous system

what is a dendrite?

appendages that are designed to receive communications from other cells.

what is an axon?

where electrical impulses from the neuron travel away to be received by other neurons.

what is the myelin sheath?

an insulating layer, or sheath, that forms around nerves, including those in brain & spinal cord.

what is the cell body?

the compact section of a nerve that contains the nucleus and the cytoplasm.

what is the difference between afferent and efferent nerves?

afferent nerves carry information to the brain. efferent nerves carry motor information to the muscles and glands.

what is the function of the pons?

conducts messages to other parts of the brain. reflex actions including chewing, tasting, and saliva production. assisting in respiration.

what is the function of the medulla?

regulating heartbeat, respiration, swallowing, coughing, and blood pressure.

what is the function of the cerebellum?

muscle coordination, balance, posture, and muscle tone.

what is the function of the pituitary gland?

growth and development. controls all other endocrine glands.

what is the function of the frontal lobe?

emotions, personality, morality, intellect, and speech.

what is the function of the parietal lobe?

sensory, motor, pain, heat, and touch.

what is the function of the occipital lobe?

vision.

what is the function of the temporal lobe?

hearing and smelling.

what is a synapse? where does it happen?

the site of transmission of electric nerve impulses. it occurs between 2 nerve cells or between a neuron and a gland or muscle cell.

what makes up the PNS?

12 cranial nerve pairs and 31 spinal nerve pairs.

what is amyotrophic lateral sclerosis? is it treatable?

a chronic, degenerative neuromuscular disease. there is no cure but drugs may slow progress.

what is a cerebrovascular accident? is it treatable?

aka a stroke. when the blood flow to the brain is impaired, resulting in a lack of oxygen and a destruction of brain tissue. "clot busting" drugs can restore blood flow.

what is multiple sclerosis? is it treatable?

a chronic, progressive, disabling condition resulting from a degeneration of the myelin sheath in the CNS. no cure but physical therapy and muscle relaxants are used to maintain functional ability for as long as possible.

what is shingles? is it treatable?

an acute inflammation of nerve cells. treatments is directed towards relieving pain and itching.

what is cerebral palsy? is it treatable?

a disturbance in voluntary muscle action caused by brain damage. no cure. physical, occupational, and speech therapy are important. drugs, muscle relaxants, casts, braces, and/or orthopedic surgery.

what is parkinson's? is it treatable?

a chronic progressive involving degeneration of brain cells. no cure. drugs are used to relieve symptoms, physical therapy can also be used.

what is meningitis? is it treatable?

inflammation of the meninges of the brain and/or spinal cord. antibiotics, antipyretics, anticonvulsants, and/or medications for pain and cerebral edema.

what is epilepsy? is it treatable?

a seizure syndrome associated with abnormal electrical impulses in the neurons of the brain. no cure. anticonvulsant drugs.

functions of epithelial tissue?

cover the surface of body & line internal organs & form gland. protection and secretion.

functions of connective tissue?

support, protect, and give structure.

functions of muscle tissue?

power & movement

functions of nervous tissue?

control & coordinate.

what are the frontal and coronal planes?

separates the body into front and back parts.

what is the transverse plane?

separates the body into top and bottom parts but will never be equal.

superior

above

inferior

below

medial

towards middle

lateral

away from middle

anterior

moving towards front (forward)

posterior

moving towards back (backwards)

superficial

towards outside

deep

inside

proximal

on a diagonal. towards midline

distal

on a diagonal. away midline

what is the ventral cavity?

made up of thoracic, abdominal, and pelvic cavities.

what is the dorsal cavity?

made up of cranial and spinal cavities.

what organs are in the hypogastric region?

small intestine, bladder, and uterus.

what happens in the epidermis?

cells grow from underneath and move to the top where they die. keratinization (the hardening of cells) occurs. Melanocytes produce melanin.

what happens in the dermis?

fingerprints are formed. blood vessels supply nutrients to the skin.

what happens in the hypodermis?

temperature regulation and storage. insulation. the connection between skin and underlying muscle.

what are active cells?

act as a repair system for the body

what happens to the body when temperature rises?

blood vessels dilate and you start to sweat

what happens to the body when tmperature falls?

blood vessels constrict and you start to shiver

what are melanocytes?

cells that produce melanin which gives your skin color.

what bones are in the axial skeleton?

the bones in your skull, neck, and vertebrae.

what bones are in the appendicular skeleton?

arms, pelvis, and legs.

how many bones are in the body?

you are born with 300 but adults have 206.

what are the types of vertebrae and how many are there?

cervical (1-7) thoracic (1-12) lumbar (1-5) sacral (1-5) coccyx(1-4)

describe skeletal muscle.

attached to bone and causes body movement that is voluntary.

what is a strain?

an injury to muscle or a band of tissue that connects muscle to bone.

what is a sprain?

an injury to the tissue that connects two bones.

what is origin?

where a muscle attaches to a bone, the end that does not move.

what is insertion?

the end that moves when a muscle contracts.

a simple fracture

a crack in the bone

a colles fracture

a crack in the distal radius

a communuted fracture

a break into 3+ pieces

a compound fracture

when bone breaks through the skin

a depressed fracture

occurs in hollow bone. a concave fracture

a dislocation

bone is removed from the joint

a greenstick fracture

bone is bent until splintering occurs

an impacted fracture

bone crushes into itself

a spiral fracture

bone twists while breaking

what is the yellow?

thalamus

what is the orange?

hypothalamus

what is the red?

pituitary gland

the midbrain

what is the purple?

what is the light blue?

pons

what is the medium blue?

medulla

what is the dark blue?

spinal cord

what is the light purple?

corpus callosum

what is the light green?

the cerebellum

open wound descriptions

an injury involving an external break in body tissue involving the skin.

inflammation

tissues are injured by bacteria or toxins and cells release chemicals that cause blood vessels to leak fluid into tissue causing swelling

diarthrosis (synovial) joints

freely moveable. ex: ball and socket or hinge

amphiarthrosis joints

slightly moveable. ex: attachment of ribs to thoracic vertebrae and symphysis pubis

synathrosis joints

immovable. ex: suture joints in cranium

process of smelling

1. breath in
2. air stimulates the olfactory cells
3. impulse travels to temporal lobe through the olfactory nerve
4. temporal nerve determines smell

process of hearing

1. sound enters external canal
2. sound hits eardrum which vibrates & send sound into middle ear
3. sound travels from middle ear to inner ear.
4. vestibulocochlear nerve is stimulated. impulse travels to the temporal lobe.

process of seeing

1. impulse occurs
2. light rays enter eye
3. optic nerve receives impulse
4. message travels to the occipital lobe

process of tasting

1. eat or drink something
2. flavors are broken down & stimulate taste buds
3. brain (pons) interprets which taste buds were activated

what are lymph vessels?

they're found throughout the body in almost all tissues that have blood vessels- pick up lymph and connect to lymph nodes

What are T cells?

develop stem cells in the red bone marrow

what are the innate defenses?

1. Species resistance
2. mechanical barriers
3. chemical barriers
4. natural killer cells
5. inflammation
6. phagocytosis
7. fever

describe species resistance

certain animals are non-susceptible to certain pathogens

describe mechanical barriers

physically block pathogens from entering body

describe chemical barriers

destroy pathogens on the outer surface, body openings, & inner linings.

describe natural killer cells

lymphocytes that respond quickly to pathogens like viruses & cancer cells

describe phagocytosis

phagocytes ingest or engulf other cells of particles

describe fever

higher temperature releases lymphocytes

what is primary immune response?

1. activation of B cells or T cells
2. plasma cells release antibodies into the lymph
3. antibodies are transported to the blood and then throughout the entire body

what is secondary immune response?

some B cells remain dormant as memory cells. if the same antigen is encountered again, these memory cells enlarge and respond rapidly

how many days does primary immune response take?

lasts 5-10 days.

how many days does secondary immune response take?

lasts 1-2 days

what is cellular immune response?

- T cells originating in red bone marrow
- primarily located in lymphatic tissue and make up 70-80% of the circulating lymphocytes in the blood
- interact directly with antigens or antigen-bearing agents to destroy them