Upgrade to remove ads
Only $2.99/month

BIO Lesson 13

Terms in this set (58)

A neurotransmitter used at the neuromuscular junction and in the autonomic nervous system; controls muscle contraction.
Acetylcholine
An enzyme that destroys acetylcholine and helps regulate muscle contraction.
Acetylcholinesterase
A protein of muscle tissue; makes up the thin filaments.
Actin
An electrical signal that travels along an axon, from a neuron to another neuron, a muscle cell, or a gland cell.
Action potential
Molecular movement that depends on the input of energy, which is necessary when the molecules to be moved are large or are being moved against their concentration gradient; one way that neurotransmitters are returned to the axon terminals.
Active transport
Peripheral neuron that brings information into the central nervous system; includes sensory neurons
Afferent neuron
Shrink or decrease in size, as in a muscle.
Atrophy
The involuntary branch of the peripheral nervous system consisting of the sympathetic and parasympathetic neurons
Autonomic nervous system
A projection from a neuron that transmits impulses away from the cell body.
Axon
A type of muscle tissue, located only in the heart, that causes the heart to pump blood through the body. These muscle cells, which are fused together and connected by gap junctions, contain many more mitochondria than other types of muscle cells.
Cardiac muscle
The part of an organism's nervous system that includes the brain and spinal cord and coordinates all nervous activity.
Central nervous system
A branched projection from a neuron that receives signals from the external environment or from other neurons.
Dendrite
A change in membrane potential, whereby the inside of the cell becomes less negative compared to the outside of the cell.
Depolarization
Peripheral neuron taking information away from the central nervous system; includes motor and autonomic neurons.
Efferent neuron
A protein that initiates and accelerates a chemical reaction in a living organism; these proteins take part in chemical reactions on the inside and outside surfaces of the plasma membrane. Involved in clearing neurotransmitters from the synapse.
Enzyme
"White" muscle fiber used for brief, powerful movements; metabolism is anaerobic and they have relatively weak endurance.
Fast twitch muscle fibers
Inability of muscle to contract.
Flaccid paralysis
The body's use of physical and chemical processes to maintain a consistent internal environment.
Homeostasis
Increase in size, as in a muscle.
Hypertrophy
An extracellular fluid that surrounds and bathes cells; consists mainly of water and also contains nutrients, raw materials, and waste products.
Interstitial fluid
An atom that carries an electrical charge, positive or negative, because it has either gained or lost an electron or electrons from its normal, stable configuration.
Ion
A type of neuron that stimulates action by conveying signals to muscles or glands and initiating a body's response to stimuli.
Motor neuron
Fatty coating insulating the axon.
Myelin sheath
A protein of muscle tissue; makes up the thick filaments.
Myosin
A control mechanism in which sensors detect changes in the internal environment and trigger effectors to counteract the change; one of the chief strategies by which organisms maintain homeostasis.
Negative feedback
A group of neurons bundled together with connective tissue.
Nerve
Network of cells (neurons), present in all multicellular animals other than sponges, that collects information about the organism's internal and external environments, processes that information, and sends signals to muscles and glands in response to the information.
Nervous system
The "excitable" cell within the nervous system that receives and transmits signals; made up of three distinctive elements: dendrites, a cell body, and an axon.
Neuron
Drug that affects the nervous system.
Neurotoxin
A chemical of the nervous system that transmits signals to adjacent cells.
Neurotransmitter
Part of the autonomic nervous system associated with being rested and well fed.
Parasympathetic neuron
The part of an organism's nervous system that transmits information to and from the central nervous system; includes the afferent (or sensory) neurons and efferent (or motor and autonomic) neurons.
Peripheral nervous system
Waves of smooch muscle contractions that propel food along the digestive tract.
Peristalsis
The study of the internal functions of organisms.
Physiology
A control mechanism in which a deviation from normal internal conditions causes an increase or acceleration of the change.
Positive feedback
A protein in the plasma membrane that binds to specific chemicals in the cell's external environment to regulate processes within the cell; for example, cells in the heart have receptor proteins that bind to adrenaline.
Receptor
Plasma membrane of a muscle cell; receives acetylcholine from a motor neuron as part of the muscle contraction process.
Sarcolemma
Smooth endoplasmic reticulum of a muscle cell; releases calcium that allows actin and myosin to bind and contract a muscle.
Sarcoplasmic reticulum
Antidepressant medications (including Prozac and Zoloft) that block serotonin from being reabsorbed and recycled by the cells (neurons) that released it, prolonging its effect. The net result for the individual is generally an elevated mood, because of serotonin's prolonged stay in the synapse.
Selective serotonin reuptake inhibitors (SSRIs)
A neurotransmitter used especially in the brain; produces feelings of contentment and satiation when released.
Serotonin
A type of muscle tissue, usually attached to bones, that is responsible for generating most of the movement in animals; accounts for about 40% of human body weight and has a striped appearance. Also called voluntary muscle.
Skeletal muscle
"Red" muscle fiber used for endurance activites; metabolism is oxidative/aerobic and fibers contain lots of mitochondria, capillaries, and myoglobin.
Slow twitch muscle fibers
A type of muscle tissue found in the walls surrounding blood vessels, the stomach and intestines, bladder, and many other organs and inner "tubes" within the body. It generates slow, rhythmic contractions that can gradually move blood, food, or other substances through the organ; not under conscious control.
Smooth muscle
Part of the autonomic nervous system associated with stress or exercise.
Sympathetic neuron
The site where a neuron communicates with another neuron, muscle cell, or gland.
Synapse
State of constant contraction of muscle.
Tetanus or tetanic paralysis
Invagination of the sarcolemma delivering action potentials deep into muscle fiber; part of muscle contraction process.
t-tubule
The duration between a contraction and relaxation when a muscle contracts; a minimum unit of contraction.
Twitch
How do the electrical signals that initiate cellular contraction pass between cardiac muscle cells?
Electrical signals in the form of moving ions pass through gap junctions.
An action potential is initiated by:
the opening of a large number of sodium ion channels.
Each neuron has two different extensions from its main central body, these are called the:
dendrites and axons.
The peripheral nervous system:
contains motor neurons.
receives information from an organism's environment.
All of these are true.
transmits signals to muscles and glands.
All of these are true.
Neurons conduct and receive information from other neurons in the form of electrical currents. The receiving end of the neuron is the _______________ while the conducting end of the neuron is the ______________. In between one neuron's conductor and other's neuron's receiver is a space called the ______________.
dendrite; axon; synapse.
Which of the following is NOT true about a synapse?
it can be a connecting point to another neuron
All of these are true about a synapse.
it can be a connecting point to a muscle
it can be a connecting point to a gland that secretes a hormone
All of these are true about a synapse.
Neurotransmitters in a synaptic cleft have all of the following possible fates EXCEPT:
inactivation by acetylcholine in the synaptic cleft.
Which of the following is NOT a type of neurotransmitter?
caffeine
Which of the following is NOT one of the major categories of vertebrate muscle cells?
respiratory muscle
When action potentials spread through a muscle fiber and causes a minimum unit of contraction, this is called a:
twitch
THIS SET IS OFTEN IN FOLDERS WITH...