Test 3 Quizzes
What is the usual age of onset for Huntington's disease?
30-50 years old
Approximately what percent of the mammalian body is composed of water?
70%
How do parallel fibers in the cerebellum control the duration of a response?
By altering the velocity of action potentials from Purkinje cells
Speaking, piano playing, athletic skills, and other rapid movements would be most impaired by damage to which structure?
Cerebellum
More Native American Pimas are overweight now than in the early 1900s because of a change in which aspect of their lives?
Diet
In movement the, ____ muscle straightens the arm.
Extensor
Anorexia is a problem stemming from a lack of appetite.
False
In Huntington's disease, earlier onset is associated with slower deterioration over time.
False
In skeletal muscles, every axon releases dopamine.
False
People with cerebellar damage are faster at shifting their attention to a particular visual location.
False
Stomach distension is necessary to produce satiety.
False
What is the relationship of genetics to Huntington's disease?
It is caused by a dominant gene on chromosome 4.
What is the effect of MPTP?
It kills the neurons that release dopamine.
What area of the brain is largely responsible for detecting osmotic pressure?
OVLT and subfornical organ
What kind of thirst is produced by an increased concentration of solutes in the blood?
Osmotic
Which of the following would most likely happen with damage to the prefrontal cortex?
Poorly planned movements
Why did mammals evolve a body temperature of 37 degrees Celsius?
They benefit from being as warm as possible and as fast as possible.
What is one reason why animals with a lesion in the lateral hypothalamus eat so little?
They experience a decreased cortical response to the smell and sight of food.
A fish swimming in cold water can swim rapidly, but fatigues much faster.
True
A striated muscle controls movement of the body in relation to the environment.
True
Control of a single muscle is distributed over a population of cells in the motor cortex.
True
Huntington's disease is controlled by an autosomal dominant gene.
True
Parkinson's symptoms usually don't appear until 70-80% of the substantia nigra neurons have died.
True
The more glutamine repeats that a person has, the earlier the age of onset of Huntington's disease.
True
The motor cortex can become active when imagining movement.
True
The prefrontal cortex plans movements according to their probable outcomes.
True
The stretch reflex is caused by a stretch of the muscle.
True
The symptoms of cerebellar damage resemble those of alcohol intoxication.
True
The prefrontal cortex plans movements according to their probable outcomes.
True
It is believed that exposure to herbicides and pesticides is ____.
a contributing factor in some cases of Parkinson's disease
A physician taps you just below the knee to check a reflex that is based on information from which kind of receptor?
a muscle spindle
Which of the following is an example of a ballistic movement?
a reflexive knee jerk
Axons release ____ at junctions with skeletal muscles.
acetylcholine
Moving a leg or arm back and forth requires opposing sets of muscles called ____.
antagonistic muscles
Poikilothermic organisms have body temperatures that ____.
are the same as the temperatures of their environments
The structure composed of the caudate nucleus, putamen, and globus pallidus is the ____.
basal ganglia
In its normal form, part of the gene that controls Huntington's disease repeats its sequence of bases ____.
between approximately 11-24 times
Leptin is produced by ____.
body fat
Which basal ganglia structure(s) is/are important for receiving input from sensory areas of the thalamus and the cerebral cortex?
caudate nucleus and putamen
Chronically high insulin levels lead to increased appetite by ____.
causing a high percentage of available glucose to be stored as fat
Vasopressin raises blood pressure by ____.
constricting the blood vessels
What effect does the hormone angiotensin II have?
constriction of blood vessels
Glucagon stimulates the liver to ____.
convert glycogen to glucose
More Native American Pimas are overweight now than in the early 1900s because of a change in which aspect of their lives?
diet
What is one of the main symptoms of Parkinson's disease?
difficulty initiating movements
The small intestine ____.
digests proteins, fats, and carbohydrates
The lateral preoptic area and surrounding parts of the hypothalamus control ____.
drinking
Genetic factors have their greatest impact on Parkinson's disease in cases that involve ____.
early onset of the disease
After damage to the lateral hypothalamus, animals ____.
eat less
An advantage of maintaining a constant body temperature is that it ____.
enables an animal to stay equally active at all environmental temperatures
After damage to the preoptic area, an animal ____.
fails to shiver and sweat sufficiently
Angiotensin II acts on the kidney to retain more sodium.
false
Purkinje cells are ____.
flat cells in sequential planes
The term ____ refers to temperature regulation and other biological processes that keep body variables within a fixed range.
homeothermic
Your posterior pituitary is most likely to release antidiuretic hormone (ADH) ____.
if you are very thirsty
Vasopressin and angiotensin II are similar in that they both promote ____.
increased blood pressure
A Golgi tendon organ responds to ____.
increases in muscle tension
The premotor cortex ____.
is active during preparations for a movement and less active during movement itself
A fever ____.
is part of the body's defense against an illness
The role of heredity in late-onset Parkinson's disease ____.
is probably not as great as with early onset Parkinson's disease
The POA/AH monitors body temperature partly by monitoring ____.
its own temperature
An animal has trouble digesting its food after damage to the ____.
lateral hypothalamus
When bacteria, viruses, fungi, or other intruders invade the body, it mobilizes ____ to attack them.
leukocytes
Movements near the midline of the body, such as bending and turning of the trunk, are controlled by which motor system?
medial tract
Most young mammals stop nursing, at least partly, due to the loss of what ability?
metabolizing the sugar in milk
What is the first point in the digestive system where enzymes begin to break down food?
mouth
A motor program is a ____.
movement that, once triggered, continues automatically until its completion
A sudden stretch of a muscle excites a feedback system that opposes the stretch. This message starts in the ____.
muscle spindles
Very brief electrical stimulation of the motor cortex results in:
muscle twitching.
Processes that reduce any discrepancies from the set point are known as ____.
negative feedback
A contraction of equal force in antagonist muscles of the arm would result in ____ of the arm.
no movement
Which area of the hypothalamus seems to be critical for the ending of meals?
paraventricular nucleus
A proprioceptor is sensitive to the ____.
position and movement of a part of the body
For most obese individuals, giving them leptin would ____.
produce little effect
The brain gets part of its information regarding low osmotic pressure from ____.
receptors around the third ventricle
Taste and other mouth sensations contribute to ____.
satiety
The psychological disorders that accompany Huntington's disease could be mistaken for which of the following?
schizophrenia
In order to elicit movement, the motor cortex ____.
sends axons to the brainstem and spinal cord
What type of muscle controls movements of internal organs?
smooth
Ghrelin is associated with ____ in the periphery and ____ in the brain.
stomach contractions; excitation of the arcuate nucleus
A physician who asks you to cross your legs and then taps just below the knee is testing your ____ reflexes.
stretch
A muscle spindle responds to the ____.
stretch of the muscle
In Parkinson's disease, which pathway in the brain degenerates?
substantia nigra to caudate nucleus and putamen
Cells in the preoptic area of the hypothalamus monitor which temperatures?
their own and the skin
A common misconception is that eating turkey increases the body's supply of ____, which enables the brain to make chemicals that make you sleepy.
tryptophan
What is a common symptom of Huntington's disease?
twitches, tremors, and writhing that interfere with voluntary movement
Mirror neurons are active when ____.
watching others perform movements
Mirror neurons are active when:
watching others perform movements.
Mirror neurons are active when ____.
watching others perform movements
The large intestine ____.
absorbs water and minerals
In its normal form, part of the gene that controls Huntington's disease repeats its sequence of bases ____.
between approximately 11-24 times
L-Dopa, a common treatment for Parkinson's disease, is a drug that ____.
increases the brain's production of dopamine
The presymptomatic test for Huntington's disease enables one to predict not only who will get the disease but also ____.
the approximate age of onset