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Cell Biology
49.
The cells that make up multicellular organisms send, receive, and respond to a variety of signals. Synaptic signaling is a form of cell-to-cell communication in which…
a cell produces a signal released into the bloodstream to be carried to specific distant organ.
adjacent cells pass molecules from one cell\'s cytoplasm to another through cell junctions.
the same cell that produces a signal also responds to the signal.
a neuron produces a chemical that induces changes in local, nearby, neurons.
50.
Match each description to the appropriate signal transduction stage.
reception transduction response
A. phytochrome receptor is activated by light signal. B, Specific genes are expressed. C. Proteins are activated through phosphorylation cascade. D. Second messenger activates specific protein kinase.
The cells that make up multicellular organisms send, receive, and respond to a variety of signals. Synaptic signaling is a form of cell-to-cell communication in which…
a cell produces a signal released into the bloodstream to be carried to specific distant organ.
adjacent cells pass molecules from one cell\'s cytoplasm to another through cell junctions.
the same cell that produces a signal also responds to the signal.
a neuron produces a chemical that induces changes in local, nearby, neurons.
50.
Match each description to the appropriate signal transduction stage.
reception transduction response
A. phytochrome receptor is activated by light signal. B, Specific genes are expressed. C. Proteins are activated through phosphorylation cascade. D. Second messenger activates specific protein kinase.
Cell Biology
37. The kidney of a given land animal has particularly short loops of Henle. Predict the type of environment in which this animal lives.
desert
wetland
temperate forest
arid mountain range
48. The cells that make up multicellular organims send, receive, and respond to a variety of signals. Which of the following is an example of direct signaling?
During wound healing, platelet cells produce a growth factor that induces nearby cells to divide.
Junctions between adjacent plant cells connect their cytoplasms and allow them to share molecules.
Mutated cancer cells produce as well as respond to growth signals, resulting in tumor growth.
Pancreas cells produce and release insulin into the bloodstream to induce liver cells to uptake and use glucose.
desert
wetland
temperate forest
arid mountain range
48. The cells that make up multicellular organims send, receive, and respond to a variety of signals. Which of the following is an example of direct signaling?
During wound healing, platelet cells produce a growth factor that induces nearby cells to divide.
Junctions between adjacent plant cells connect their cytoplasms and allow them to share molecules.
Mutated cancer cells produce as well as respond to growth signals, resulting in tumor growth.
Pancreas cells produce and release insulin into the bloodstream to induce liver cells to uptake and use glucose.
Cell Biology
32. Organisms use a variety of excretory systems to filter metabolic wastes out of their body fluid (blood, coelomic fluid, or hemolymph). Match each organism to the type of filtration structure it contains.
Prontonephridia metanephridia malpighian tubules Nephrons
annelids insects humans flatworms arachnids molluscs roitfers birds
36
Match each function to its site of action in the nephron.
glomenulus proximal convoluted tubule descending limb of loop of Henle Distal convoluted tubule ascending limb of loop of Henle collecting duct
1, regulation of NaCl and K in bodily fluids by secreting K and reabsorbing NaCL 2. transport of filrate to renal pelvis. 3. filration of blood plasma 4. reabsorption of water only, increasing solute concentration of filtrate 5. reabsorption of nutrients such as glucose. 6. reabsorption of salt only, during filtrate.
Prontonephridia metanephridia malpighian tubules Nephrons
annelids insects humans flatworms arachnids molluscs roitfers birds
36
Match each function to its site of action in the nephron.
glomenulus proximal convoluted tubule descending limb of loop of Henle Distal convoluted tubule ascending limb of loop of Henle collecting duct
1, regulation of NaCl and K in bodily fluids by secreting K and reabsorbing NaCL 2. transport of filrate to renal pelvis. 3. filration of blood plasma 4. reabsorption of water only, increasing solute concentration of filtrate 5. reabsorption of nutrients such as glucose. 6. reabsorption of salt only, during filtrate.
Cell Biology
30
Freshwater and marine fish inhabit waters with different osmotic properties, so they regulate osmolarity in different ways. Classify each of the osmoregulation properties as relevant to freshwater fish or marine fish.
1. ingest large amounts of water and salt through mouth. 2. constantly gain water by osmosis. 3. excrete large amounts of water in urine. 4. gain salt ions through gills.
5. constantly lose water by osmosis. 6. excrete large amount of salt in urine. 7. Excrete large amounts of salt through gills. 8. Ingest little to no water by mouth.
31.
What is the primary benefit for an animal to excrete nitrogenous waste as uric acid?
Uric acid requires less energy to synthesize than urea.
Uric acid helps an animal to conserve water.
Uric acid increases efficiency of kidney function.
Uric acid improves gastric absorption of nucleic acids.
Freshwater and marine fish inhabit waters with different osmotic properties, so they regulate osmolarity in different ways. Classify each of the osmoregulation properties as relevant to freshwater fish or marine fish.
1. ingest large amounts of water and salt through mouth. 2. constantly gain water by osmosis. 3. excrete large amounts of water in urine. 4. gain salt ions through gills.
5. constantly lose water by osmosis. 6. excrete large amount of salt in urine. 7. Excrete large amounts of salt through gills. 8. Ingest little to no water by mouth.
31.
What is the primary benefit for an animal to excrete nitrogenous waste as uric acid?
Uric acid requires less energy to synthesize than urea.
Uric acid helps an animal to conserve water.
Uric acid increases efficiency of kidney function.
Uric acid improves gastric absorption of nucleic acids.
Cell Biology
27
Which of the following statements describes saltatory conduction?
Conduction occurs exclusively at nodes of Ranvier.
Voltage-gated sodium channels open, depolarizing unmyelinated axons.
Voltage-gated potassium channels open, depolarizing myelinated axons
Conduction occurs along unmyelinated axons, decreasing conduction velocity.
28
What is temporal summation?
combination of postsynaptic potentials due to the repeated stimulation of a single synapse
predisposition for a neuron to be excited due to previous stimuli shifting the baseline potential towards threshold
addition of postsynaptic potentials due to the simultaneous stimulation of multiple synapses
interaction between inhibitory postsynaptic potentials and excitatory postsynaptic potentials
Which of the following statements describes saltatory conduction?
Conduction occurs exclusively at nodes of Ranvier.
Voltage-gated sodium channels open, depolarizing unmyelinated axons.
Voltage-gated potassium channels open, depolarizing myelinated axons
Conduction occurs along unmyelinated axons, decreasing conduction velocity.
28
What is temporal summation?
combination of postsynaptic potentials due to the repeated stimulation of a single synapse
predisposition for a neuron to be excited due to previous stimuli shifting the baseline potential towards threshold
addition of postsynaptic potentials due to the simultaneous stimulation of multiple synapses
interaction between inhibitory postsynaptic potentials and excitatory postsynaptic potentials
Cell Biology
23.
What is an equilibrium potential
the potential across a membrane at which flow of a specific ion into the cell equals the flow out of the cell
the difference in positive and negative charge across the membrane of an unstimulated, resting cell
the transmembrane potential at which there is no movement of any individual ions into or out of the cell
26
Action potentials in neurons involve opening and closing of voltage-gated Na and K ion channels. Place the events of an action potential in order, starting and ending with a cell at its resting membrane potential.
1. K rushes out the cell, causing repolarization 2. a graded potential brings the membrane to threshold potential. 3. K channels fully open, and Na channel inactivation gates close. 4. Na rushes into cell, causing membrane depolarization. 5. Fast Na and slow K channels are activated. 6. K channels close slowly resulting in hyperpolarization Na channel gate reset
What is an equilibrium potential
the potential across a membrane at which flow of a specific ion into the cell equals the flow out of the cell
the difference in positive and negative charge across the membrane of an unstimulated, resting cell
the transmembrane potential at which there is no movement of any individual ions into or out of the cell
26
Action potentials in neurons involve opening and closing of voltage-gated Na and K ion channels. Place the events of an action potential in order, starting and ending with a cell at its resting membrane potential.
1. K rushes out the cell, causing repolarization 2. a graded potential brings the membrane to threshold potential. 3. K channels fully open, and Na channel inactivation gates close. 4. Na rushes into cell, causing membrane depolarization. 5. Fast Na and slow K channels are activated. 6. K channels close slowly resulting in hyperpolarization Na channel gate reset
Cell Biology
19.
Which of the following describes how neurons use neurotransmitters to communicate with one another?
The axons of one neuron connect to the axons of another neuron to relay information through neurotransmitter release.
At synapses, dendrites release neurotransmitters that are recognized by proteins on axons.
Axons fuse with dendrites to produce a continuous cellular body that allows neurotransmitters to flow from one neuron to another.
At synapses, axons release neurotransmitters that are recognized by proteins on dendrites.
21.
Select the descriptions that apply to the sodium-potassium pump. More than one answer
Sodium ions and potassium ions move into and out of the plasma membrane by osmosis.
The pump helps to maintain the concentration of sodium and potassium ions in living cells.
The pump is an active mechanism for transporting ions through the plasma membrane.
The concentration gradient of the ions determines the direction of movement through the pump.
Which of the following describes how neurons use neurotransmitters to communicate with one another?
The axons of one neuron connect to the axons of another neuron to relay information through neurotransmitter release.
At synapses, dendrites release neurotransmitters that are recognized by proteins on axons.
Axons fuse with dendrites to produce a continuous cellular body that allows neurotransmitters to flow from one neuron to another.
At synapses, axons release neurotransmitters that are recognized by proteins on dendrites.
21.
Select the descriptions that apply to the sodium-potassium pump. More than one answer
Sodium ions and potassium ions move into and out of the plasma membrane by osmosis.
The pump helps to maintain the concentration of sodium and potassium ions in living cells.
The pump is an active mechanism for transporting ions through the plasma membrane.
The concentration gradient of the ions determines the direction of movement through the pump.
Cell Biology
What is the primary benefit for an animal to excrete nitrogenous waste as uric acid?
Uric acid requires less energy to synthesize than urea.
Uric acid is highly toxic to predators.
Uric acid increases efficiency of kidney function.
Uric acid improves gastric absorption of nucleic acids.
Uric acid helps an animal to conserve water.
The kidney of a given land animal has particularly short loops of Henle. Predict the type of environment in which this animal lives.
a. temperate forest
b. arid mountain range
c. desert
d. wetland
Uric acid requires less energy to synthesize than urea.
Uric acid is highly toxic to predators.
Uric acid increases efficiency of kidney function.
Uric acid improves gastric absorption of nucleic acids.
Uric acid helps an animal to conserve water.
The kidney of a given land animal has particularly short loops of Henle. Predict the type of environment in which this animal lives.
a. temperate forest
b. arid mountain range
c. desert
d. wetland
Cell Biology
Which of the following statements describes saltatory conduction?
Voltage-gated sodium channels open, depolarizing unmyelinated axons
Voltage-gated potassium channels open, depolarizing myelinated axons.
Conduction occurs exclusively at nodes of Ranvier.
Conduction occurs along unmyelinated axons, decreasing conduction velocity.
What is temporal summation?
addition of postsynaptic potentials due to the simultaneous stimulation of multiple synapses
interaction between inhibitory postsynaptic potentials and excitatory postsynaptic potentials
combination of postsynaptic potentials due to the repeated stimulation of a single synapse
predisposition for a neuron to be excited due to previous stimuli shifting the baseline potential towards threshold
Voltage-gated sodium channels open, depolarizing unmyelinated axons
Voltage-gated potassium channels open, depolarizing myelinated axons.
Conduction occurs exclusively at nodes of Ranvier.
Conduction occurs along unmyelinated axons, decreasing conduction velocity.
What is temporal summation?
addition of postsynaptic potentials due to the simultaneous stimulation of multiple synapses
interaction between inhibitory postsynaptic potentials and excitatory postsynaptic potentials
combination of postsynaptic potentials due to the repeated stimulation of a single synapse
predisposition for a neuron to be excited due to previous stimuli shifting the baseline potential towards threshold
Cell Biology
Select the descriptions that apply to the sodium-potassium pump. (more than one answer)
The concentration gradient of the ions determines the direction of movement through the pump.
The pump helps to maintain the concentration of sodium and potassium ions in living cells.
Sodium ions and potassium ions move into and out of the plasma membrane by osmosis.
The pump is an active mechanism for transporting ions through the plasma membrane.
What is an equilibrium potential?
the state at which positive and negative charge distribution for an ion across a membrane is equal, therefore there is no net ion movement
the potential across a membrane at which flow of a specific ion into the cell equals the flow out of the cell
the transmembrane potential at which there is no movement of any individual ions into or out of the cell
the difference in positive and negative charge across the membrane of an unstimulated, resting cell
The concentration gradient of the ions determines the direction of movement through the pump.
The pump helps to maintain the concentration of sodium and potassium ions in living cells.
Sodium ions and potassium ions move into and out of the plasma membrane by osmosis.
The pump is an active mechanism for transporting ions through the plasma membrane.
What is an equilibrium potential?
the state at which positive and negative charge distribution for an ion across a membrane is equal, therefore there is no net ion movement
the potential across a membrane at which flow of a specific ion into the cell equals the flow out of the cell
the transmembrane potential at which there is no movement of any individual ions into or out of the cell
the difference in positive and negative charge across the membrane of an unstimulated, resting cell
