Chapters 35 and 36 (Human Body Unit p.1) Flashcards
what do the levels of organization in a multicellular organism include?
cells, tissues, organs, and organ systems
what structures make up the nervous system?
brain, spinal cord, peripheral nerves
what is the function of the nervous system?
recognizes and coordinates the body’s response to changes in its internal and external environments
what structures make up the integumentary system?
skin, hair, nails, sweat and oil glands
what is the function of the integumentary system?
serves as a barrier against infection and injury; helps to regulate body temperature; provides protection against ultrviolet radiation from the sun
what structures make up the respiratory system?
nose, pharynx, larynx, trachea, bronchi, bronchioles, lungs
What is the function of the respiratory system?
provides oxygen needed for cellular respiration and removes excess carbon dioxide from the body
what structures make up the digestive system?
mouth, pharynx, esophaagus, stomach, small and large intestines, rectum
what is the function of the digestive system?
converts foods into simpler molecules that can be used by the cells of the body; absorbs food; eliminates waste
what structures make up the excretory system?
skin, lungs, kidneys, uretors, urinary bladder, uretha
what is the function of the excretory system?
eliminates waste products from the body in ways that maintain homeostasis
what structures make up the skeletal system?
bones, cartilage, ligaments, tendons
what is the function of the skeletal system?
supports the body; protects internal organs; allows movement; stores mineral reserves; provides a ssite for blood cell formation
what structures make up the muscular system?
skeletal muscle,smooth muscle, cardiac muscle
what is the function of the muscular system?
works with skeletal system to produce voluntary movement; helps to circulate blood and move food through the digestive system
what structures make up the circulatory system?
heart, blood vessels, blood
what is the function of the circulatory system?
brings oxygen, nutrients, and hormones to cells; fights infection; removes cell wastes; helps to regulate body temperature
what structures make up the endocrine system?
hypothalamus, pituitary, thyroid, parathryoids, adrenals, pancreas, ovaries, testes
what is the function of the endocrine system?
controls growth development, and metabolism; maintains homeostasis
what structures make up the reproductive system?
testes, epididymis, vas deferens, uretha, and penis; ovaries, fallopian tubes, uterus, vagina
what is the function of the reproductive system?
produces reproductive cells; in females, nurtures and protects developing embryo
what structures make up the lymphatic/immune systems?
white blood cells, thymus, spleen, lymph nodes, lymph vessels
what are specilaized cells?
cells that are uniquely suited to perform a particular function.
what is epithelial tissue?
glands and tissues that cover interior and exterior body surfaces.
what is connective tissue?
provides support for the body and connects it’s parts
what is nervous tissue?
transmits nerve impulses throughout the body.
what is muscle tissue?
along with bones, enables the body to move
what is homeostasis?
the process by which organisms keep internal conditions relatively constant despite changes in external environments. Homeostasis in the body is maintained by feedback loops
what is feedback inhibition?
the process in which a stimulus produces a response that opposes the original stimulus
what does the nervous system do?
controls and coordinates functions throughout the body and responds to internal and external stimuli.
what are neurons?
cells that transmit impulses
sensory neurons
carry impulses from the sense organs to the spinal cord and brain
motor neuorns
carry impulses from the brain and the spinal cord to muscles and glands
interneurons
connect sensory and motor neurons aand carry impulses between them
cell body
largest part of neuron; contains the nucleus and most of the cytoplasm; most of the metabolic activity of the cell takes place here
dendrites
extensions that branch off from the cell body; carry impulses from the environment or form other neurons toward the cell body.
axon
long fiber that carries impulses away from the cell body
myelin sheath
an insulating membrane that surrounds the axon in some neurons; surrounds a single long axon leaving many gaps called nodes
resting potential
the electrical charge across the cell membrane of a neuron in its resting state
how does an impulse begin?
when a neuron is stimulated by another neuron or the environment
action potential
the reversal of charges, from negative to positive, is called a nerve impulse
synapse
the location at which a neuron can transfer an impulse to another cell
neurotransmitters
chemicals used by a neuron to transmit an impulse across a synapse to another cell
what is the function of the central nervous system?
to relay information, process information, and analyze information
meninges
connective tissue that surrounnds both the brain and the spinal cord
cerebrospinal fluiid
baths the brain and spinal cord and acts as a shock absorber that protects the central nervous system
cerebellum
the largest and most prominent region of the human brain; responsible for the voluntary, or conscious, activities of the body
cerebrum
second largest region of the brain; located at the back of the skull; coordinates and balances the actions of the muscles so that the body can move gracefully and efficiently
brain stem
connects the brain and the spinal cord; regulate the flow of information between the brain and the rest of the body.
hypothalamus
the control center for recognition and analysis of hunger, thirst,fatigue, anger, and body temperature
thalnamus
recieves messages from all of the sensory receptors throughout the body and then relays the information for further processing
reflex
a quick automatic response to a stimulus
What does the sensory division of the peripheral nervous system do?
transmits impulses from sense organs to the central nervous system. The motor division transmits impulses from the central nervous system to the muscles or glands
reflex arc
the pathway that an impulse travels from your foot back to your leg
sensory receptors
neurons that react directly to stimuli from the envionment, includiing light, sound, motion, chemicals, pressure, and changes in temperature
what are the five general categories of sensory receptors?
pain receptors, thermoreceptors, mechanoreceptors, chemoreceptors, and photoreceptor
pupil
tiny muscles in the iris adjust the size of the pupil to regulate the amount of light that enters the eye
lens
small muscles attached to the lensss change its shape to help you adjust your eyes’ focus to near or distant objects
retina
photoreceptors are arranged in a layer in the retina. The photoreceptors convert light energy into nerve impulses that are carried to the central nervous system.
rods
a type of photoreceptor that is extremely sensitive to light, but they do not distinguish different colors
cones
photoreceptors that are less sensitive than rods, but they do respond to light of different colors, producing color vision
cochlea
a fluid filled part of the inner ear
semicircular canals
monitor the position of your body, especially your head, in relation to gravity
taste buds
sense organs that detect taste
drug
any substance, other than food, that changes the structure or function of the body.
stimulants
a type of drug that increases heart rate, blood pressure, and breathing rate. In addition , stimulants increase the release of neurotransmitters at some synapses in the brain
depressants
a type of drug that slows down heart rate, lower blood pressure, relax muscles, and relieve tension
what does cocaine cause?
the sudden release in the brain of a neurotransmitter called dopamine.
what are opiates?
they mimic natural chemicals in the brain known as endorphins, which normally help to overcome sensations of pain.
what is alcohol?
a depressant that slows done the rate at which the central nervous system functions.
what is fetal alcohol syndrome?
a group of birth defects caused by the effects of alcohol on the fetus.
drug abuse
the intentional misuse of any drug for nonmedical purposes
addiction
an uncontrollable dependence on a drug
what does the skeletal system do?
supports the body, protects internal organs, provides for movement, stores mineral reserves, and provides a site for blood cell formation
bones
a solid network of living cells and protein fibers that are surrounded by deposits of calcium salts.
periosteum
a tough layer of connective tissue
haversian canals
a network of tubes that contain blood vessels and nerves
bone marrow
soft tissue found inside bone cavaties
cartilage
a type of connective tissue made up of protein fibers such as collagen and flexible elastin
ossification
the process in which cartilage is replaced by bone
joint
a place where one bone attaches to another bone
how are joints classified?
depending on their type of movement; they can be immovable, slightly movable, or freely movable
ligaments
strips of tough connective tissue that hold bones together in a joint
what are the three types of muscle?
skeletal, smooth and cardiac
myosin
a protein contained in thick filaments
actin
a protein that makes up thin filaments
when does a muscle contract?
when the thin filaments in the muscle fiber slide over the thick filaments
neuromuscular junction
the point of contact between a motor neuron and a skeletal muscle cell
acetylcholine
a neurotransmitter that is released from the vesicles in an axon terminal
tendons
tough connective tissue that joins skeletal muscles to bones
why is regular exercise important?
it helps maintain muscular strength and flexibility
integumentary system
serves as a barrier against infection and injury, helps to regulate body temperature, removes waste products from the body, and provides protection against ultraviolet radiation from the sun.
epidermis
the outer layer of the skin
keratin
a tough fibrous protein that makes up hair and nails
melanin
a dark brown pigment produced by melanocytes, helps protect the skin from UV light
dermis
the inner layer of the skin
what are the two major glands contained in the dermis
sweat glands and sebaceous glands (oil glands)
hair follicles
tubelike pockets of epidermal cells that extend into the dermis. the base where hair grows
