Lab Quiz 2 - 1 Flashcards
A single muscle contraction is called:
A twitch
a single action potential
Type I muscle fibers:
Slow twitch Primarily aerobic lots of mitochondria lots of myoglobin lots of capillaries
Myoglobin:
red protein containing heme which stores oxygen in muscles
Type II muscle fibers:
Fast twitch Primarily anaerobic Few of mitochondria little myoglobin Few capillaries
Tropomyosin:
Troponin is attached to it.
Ca2+ binding to tropomyosin shifts it away from active site of myosin
Troponin:
Blocks crossbridge formation.
Binds to tropomyosin
What is required for muscle contraction to occur?
ATP
Ca2+
Magnesium
Example of a:
- Fast Twitch:
- Slow Twitch:
- Fast Twitch:
Eye - Slow Twitch:
Soleus in lower calf
Motor unit:
Somatic motor neuron, and all muscle fibers it innervates
Motor unit summation:
- Define:
- How does it work?
- Define:
Gradual addition of muscle fibers (one motor unit at a time) - How does it work?
Recruits slow twitch and smaller muscle fibers first, increased signal strength causes additional recruitment of fast twitch muscle fibers
Wave (temporal) summation (muscular innervation):
Muscle contractions build on each other. As they come more and more quickly, the muscle no longer has time to relax. It becomes in a continual state of contraction: tetanus
Tetanus:
Continual state of contraction, results from temporal summation
A sustained contraction (multiple action potentials)
Products of muscles running in:
- Anaerobic:
- Aerobic:
- Anaerobic:
Lactic acid - Aerobic:
CO2 and H2O
Lactic acid and muscle fatigue:
- Define:
- Duration:
- Utilization of lactic acid:
- Define: Lowers pH, causing enzymes in muscle fibers to have reduced activity - Duration: Does not cause longterm fatigue - Utilization of lactic acid: Shuttled to liver for gluconeogenesis
Muscle fatigue:
The inability to sustain a contraction
Glycogen depletion and fatigue:
This will cause fatigue, in longterm
Why can sprinters perform multiple heats in a day but long distance runners cannot.
Sprinters will not deplete glycogen stores, they will simply cause lactic acid build up, which will be taken care of by the liver (gluconeogenesis)
Long distance runners cannot, because glycogen stores will be depleted
What is the device we squeezed in class called?
- What is the range for a male?
- What is the range for a female?
Hand dynamometer - What is the range for a male? 40 - 65 kg (50 average) - What is the range for a female? 20 - 38 (28 average)
What is the fastest number of squeezes I can do in a second?
Why?
~5
< 10
Because necessary time to relax before firing again (Ca2+ must go out and back in)
Parts of a sarcomere:
IZIAHMHA I Z: actin connecting middle line I: Actin only A: All of myosin H: only myosin (where it doesn't overlap with actin) M: middle of myosin H A
Glycerination of muscle has what effect?
Makes membrane permeable
Disrupts the tropomyosin-troponin complex (making Ca2+ unnecessary for muscle contraction)
Anterior:
Posterior:
Anterior (Rostral):
Towards face/front of brain
Posterior (Caudal):
Towards back of head/back of brain
Lateral:
Medial:
Lateral: towards the side
Medial: towards the middle
Dorsal (head):
Ventral (head):
Dorsal (head): towards the top Back (for most of the body) Ventral (head): towards the bottom front (for most of the body)
Frontal plane:
- Divides:
- Other name:
- Divides:
front from back (Can be drawn at any point if it is in the right orientation) - Other name:
Coronal plane
Sagittal plane:
- Divides:
- Mid sagittal plane:
- Divides:
Left from right (Can be drawn at any point if it is in the right orientation) - Mid sagittal plane:
In the brain exists directly between the left and right hemisphere
Horizontal plane:
- Divides:
- Divides:
Top from bottom (makes a horizon line)
(Can be drawn at any point if it is in the right orientation)
Three layers of the meninges:
Dura mater
Arachnoid mater
(subarachnoid space)
pia mater
Dura mater:
Tough outer layer
Arachnoid layer:
runs below the dura mater
Where are blood vessels located on the outside of the brain?
Subarachnoid space (between the arachnoid mater and the pia mater)
Pia mater:
Innermost layer
Only meninges layer which follows the gyri and sulci of the brain
In appearance may be indistinguishable from the brain
What is the brainstem composed of?
The medulla, pons, and cerebellum
Location:
- Pons:
- Medulla:
- Cerebellum:
- Pons:
Bulge above the cerebellum - Medulla:
last inch of the spinal cord (before meeting the brain) - Cerebellum:
mini-brain, posterior to the pons and medulla
Pituitary gland:
- Location:
- Size:
- Location: anterior to the pons ventral to the hypothalamus - Size: pea sized
Olfactory bulbs (there are two):
- Location:
- Nerve route:
- Prior to or after decussation?
- Location:
Ventral portion of the brain, anterior
Under the frontal lobe
What nerves are visible (hint/pun) from the ventral portion?
The optic nerve (cranial II) Optic chiasma (decussation of optic nerve) Oculomotor nerve (cranial nerve III)
Nerve:
Tract:
Nerve: Axons in the PNS
Tract: Axons in the CNS
Longitudinal fissure:
Divides the two halves of the brain
Cranial nerve III:
- Name:
- Function:
- Name:
oculomotor nerve - Function:
Innervates muscles of the eye
Flow of information from eye to the brain:
Optic nerve (cranial II) -> optic chiasma (decussation) -> towards center of brain
Where is the 4th ventricle?
between the pons and cerebellum
anterior to the cerebellum
posterior to the pons
It will be bisected by a midline sagittal cut
When does one end and the other start?
Optic Nerve:
Optic Tract:
Optic Nerve:
Exists prior to the optic chiasma
Optic Tract:
Continues past the optic chiasma
Four lobes and positions:
Outer surface of the brain Frontal: front Parietal: top Occipital: back of head Temporal: side of head
Band of fibers that connect two sides of the CNS is a (usually contains nervous tissue)?
Commissure
Sagittal midline cut will bisect:
Corpus callosum Pineal gland Hypothalamus Cerebellum Pons Medulla Third ventricle hypophysis thalamus
Third ventricle location:
Along the sagittal midline.
Dorsal (right above) the thalamus and hypothalamus
Pineal body (gland) location?
Posterior to the thalamus, on the floor of the third ventricle
Basal ganglia:
- Composed of:
- Location:
- Composed of: Globus pallidus, putamen, and caudate nucleus - Location: Lies just lateral to the third ventricle. Level with the third ventricle A little higher than the thalamus Above the optic chiasma Anterior to the thalamus
Rostral:
Caudal:
Towards face
Towards back of head
Name for cerebellum white matter?
Translation?
Arbor vitae (tree of life)
Lateral ventricles:
- Position:
- Position:
Flanks the brain, dorsal to the 3rd ventricle (and 4th for that matter), also lateral to both.
The corpus callosum is directly above them
Corpus Callosum is a:
Commissure of the brain
Anterior commissure is directly above the:
optic chiasma
Hippocampus:
- Location:
Elongated ridges on the floor of the lateral ventricles
Process of gradual recuitment of additional muscle fibers is called:
Motor Unit Summation
What are the names of the three planes mentioned in class?
frontal (coronal) plane
sagittal plane
horizontal plane
