NERVOUS
Which type of cell forms myelin around axons in the peripheral nervous system?
What are Schwann cells?
Put these in order from simplest to most complex: organ, organism, cell, tissue, organ system.
Cell → tissue → organ → organ system → organism
In simple diffusion, molecules move from an area of _____ concentration to an area of _____ concentration.
What are high to low?
What transport mechanism uses ATP directly to move substances against their concentration gradient?
What is primary active transport?
These are the structural and functional units of the nervous system.
What are neurons?
Which CNS glial cell forms myelin?
What are oligodendrocytes?
These are the four primary tissue types.
What are muscle, nervous, epithelial, and connective tissue?
A red blood cell is placed into a solution with a higher solute concentration than the cell. Will the cell swell or shrink?
What is shrink?
The sodium-potassium pump moves how many sodium ions out of the cell and how many potassium ions into the cell per ATP?
3 Na⁺ out and 2 K⁺ in.
Which part of a neuron primarily receives incoming signals and conducts graded impulses toward the cell body? Which part of a neuron conducts action potentials away from the cell body?
What are dendrites? What is the axon?
Which glial cells act like the immune cells of the CNS by phagocytizing pathogens and cellular debris?
What are microglia?
A physician examines a tissue containing cells surrounded by abundant extracellular material containing protein fibers and ground substance. Which primary tissue type is most likely being examined, and what feature makes it different from epithelial tissue?
What is connective tissue? It has abundant extracellular matrix surrounding its cells.
A red blood cell is placed in a hypotonic solution. In which direction will water move?
What is into the cell?
Glucose enters a cell by moving down the sodium concentration gradient. What type of transport is this?
What is secondary active transport?
A sensory receptor detects a painful stimulus in your hand. The neuron carrying that information toward the CNS is classified as what?
What is a sensory/afferent neuron?
This is the glial cell that helps regulate the extracellular environment of neurons, contributes to the blood-brain barrier, and takes up excess neurotransmitters.
What is an astrocyte?
A structure contains epithelial tissue, connective tissue, nervous tissue, and muscle tissue. What level of organization does this structure represent?
What is an organ?
Two solutions have the same osmolality, but one contains a solute that can freely cross the cell membrane and the other contains a solute that cannot. Can they necessarily be considered equally isotonic? Explain.
No. Tonicity depends on whether the solute can cross the membrane. A permeable solute may enter the cell and cause water to follow, changing cell volume.
A neuron is sitting at approximately −70 mV. The membrane suddenly becomes much more permeable to Na⁺. Will the membrane potential become more positive or more negative? Explain.
More positive, because Na⁺ has a high concentration outside the cell and its equilibrium potential is positive. Increasing Na⁺ permeability drives the membrane potential toward the Na⁺ equilibrium potential.
A neuron has several dendrites and one axon. What structural classification does it belong to, and is this type common or uncommon?
What is a multipolar neuron, and it is the most common type?
A patient has damage to the myelin surrounding peripheral axons. Would you expect Schwann cells or oligodendrocytes to be involved?
Schwann cells, because they produce myelin in the PNS. Oligodendrocytes produce myelin in the CNS.
A researcher removes a tissue sample and finds cells embedded within a semi-solid ground substance. The cells are called chondrocytes. What type of connective tissue is this, and what major role does it play during development?
What is cartilage? It serves as a template for the developing skeleton.
A student drinks an extremely concentrated salt solution. The osmolarity of their extracellular fluid increases. Which direction will water move relative to their cells?
Out of the cells, because the extracellular environment has a higher effective solute concentration.
A drug completely inhibits the Na⁺/K⁺ pump. Predict two major consequences this would have on a cell.
A patient has a peripheral nerve that has been cut. Why does it have a better chance of regeneration than a severed CNS axon?
Schwann cells can form a regeneration tube and release growth factors, whereas CNS regeneration is inhibited by several factors including inhibitory proteins and glial scars.