Bio 1201 Final QUESTIONS AND ANSWERS
Which of the following is NOT an endocrine organ?
Hypothalamus, Ovary, Thyroid, Adrenal Glands
Hypothalamus
As a baby breastfeeds, more oxytocin is released by the mother's posterior
pituitary. This is an example of
feedback inhibition (positive)
Which gland releases hormones that help with the body's response to stress?
Adrenal Gland
Which of the following correctly matches the hormone to its function?
Prolactin: milk production, Calcitonin: decreases levels of Ca2+ in the blood,
Progesterone: preparing and maintaining the uterus
When epinephrine binds to cardiac (heart) muscles cells, it speeds up their
contraction. When it binds to muscle cells of the small intestine, it inhibits their
contraction. Which of the following best accounts for the fact that the same
hormone can have different effects on the muscle cells?
The two types of muscle cells have different signal transduction pathways for
epinephrine and thus have different cellular responses
What is the central nervous system?
Where integration takes place; this includes the brain and nerve cord (spinal cord)
What is the periphal nervous system?
the sensory and motor neurons that connect to the CNS, which carries info in and out of
the CNS, all the other nerves throughout the body
How are sensory neurons, interneurons, and motor neurons different?
Sensory neurons: transmit info about external stimuli such as light, smell, touch
Interneurons: analyze and interpret info
Motor neurons: transmit signals to muscle cells, causing them to contract
How is an electrical neuron signal different from a chemical neuron signal?
, Electrical: long distance, gap junctions
Chemical: short distance, use neurotransmitters
Where does a signal enter a neuron? Where does it exit?
Enters through the dendrite and exits through the synapse terminal (axon)
What is meant by the term "resting potential"? What are the concentrations of K+
and Na+ associated with this state?
Resting potential: the membrane potential of a neuron not sending signals
-lots of K+ channels, fewer Na+ channels
-negative membrane potential
-neuron is not signaling
How do changes in membrane potential occur? What type of membrane transport
protein is associated with these changes?
occur bc neurons contain gated ion channels that open and close in response to stimuli
(ap)
-voltage gated ion channels
What needs to happen so that an action potential can be fired?
depolarization (sodium ions cause membrane potential to be less negative)
What are the 5 stages of action potential firing and what is happening in each?
1. resting potential-neuron is resting
2. depolarization-sodium channels begin to open
3. action potential- sodium rushes into the cell causing the inside of the cell to be
positive
4. falling phase of action potential- positive charge flows out of the cell, sodium
channels close, potassium channels open taking positive charge out of the cell
5. undershoot-occurs when the charge drops below the initial resting potential, making
the potassium pumps close, the pumps then help restore the initial resting potential
As an action potential is fired, the neuron is finally able to communicate with the
neighboring cell. What exactly is happening at the chemical synapse of a neuron?
point where neurotransmitters sit in between pre and post synaptic neuron
How is the post-synaptic cell receiving the neurotransmitter from the pre-synaptic
cell? What are the two types of postsynaptic signals that can be created?
Which of the following is NOT an endocrine organ?
Hypothalamus, Ovary, Thyroid, Adrenal Glands
Hypothalamus
As a baby breastfeeds, more oxytocin is released by the mother's posterior
pituitary. This is an example of
feedback inhibition (positive)
Which gland releases hormones that help with the body's response to stress?
Adrenal Gland
Which of the following correctly matches the hormone to its function?
Prolactin: milk production, Calcitonin: decreases levels of Ca2+ in the blood,
Progesterone: preparing and maintaining the uterus
When epinephrine binds to cardiac (heart) muscles cells, it speeds up their
contraction. When it binds to muscle cells of the small intestine, it inhibits their
contraction. Which of the following best accounts for the fact that the same
hormone can have different effects on the muscle cells?
The two types of muscle cells have different signal transduction pathways for
epinephrine and thus have different cellular responses
What is the central nervous system?
Where integration takes place; this includes the brain and nerve cord (spinal cord)
What is the periphal nervous system?
the sensory and motor neurons that connect to the CNS, which carries info in and out of
the CNS, all the other nerves throughout the body
How are sensory neurons, interneurons, and motor neurons different?
Sensory neurons: transmit info about external stimuli such as light, smell, touch
Interneurons: analyze and interpret info
Motor neurons: transmit signals to muscle cells, causing them to contract
How is an electrical neuron signal different from a chemical neuron signal?
, Electrical: long distance, gap junctions
Chemical: short distance, use neurotransmitters
Where does a signal enter a neuron? Where does it exit?
Enters through the dendrite and exits through the synapse terminal (axon)
What is meant by the term "resting potential"? What are the concentrations of K+
and Na+ associated with this state?
Resting potential: the membrane potential of a neuron not sending signals
-lots of K+ channels, fewer Na+ channels
-negative membrane potential
-neuron is not signaling
How do changes in membrane potential occur? What type of membrane transport
protein is associated with these changes?
occur bc neurons contain gated ion channels that open and close in response to stimuli
(ap)
-voltage gated ion channels
What needs to happen so that an action potential can be fired?
depolarization (sodium ions cause membrane potential to be less negative)
What are the 5 stages of action potential firing and what is happening in each?
1. resting potential-neuron is resting
2. depolarization-sodium channels begin to open
3. action potential- sodium rushes into the cell causing the inside of the cell to be
positive
4. falling phase of action potential- positive charge flows out of the cell, sodium
channels close, potassium channels open taking positive charge out of the cell
5. undershoot-occurs when the charge drops below the initial resting potential, making
the potassium pumps close, the pumps then help restore the initial resting potential
As an action potential is fired, the neuron is finally able to communicate with the
neighboring cell. What exactly is happening at the chemical synapse of a neuron?
point where neurotransmitters sit in between pre and post synaptic neuron
How is the post-synaptic cell receiving the neurotransmitter from the pre-synaptic
cell? What are the two types of postsynaptic signals that can be created?
