Final Exam Flashcards

1
Q

A group of cells working together to perform a function is a __________

A

Tissue

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2
Q

The four different types of tissues are _______

A

Epithelial
Connective
Muscle
Nervous

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3
Q

When food enters the stomach, gastric cells will increase blood flow to the stomach without any need for external signaling. This homeostasis mechanism is known as _______

a. Dynamic Equilibrium
b. Extrinsic Regulation
c. Autoregulation
d. Feed-Forward Regulation

A

c. Auto-regulation

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4
Q

Which of the following statements is false, regarding pinocytosis?

a. Pinocytosis is a method of endocytosis
b. Pinocytosis allows a cell to bring in substances from the extracellular environment
c. Pinocytosis is less specific than receptor-mediated endocytosis
d. Pinocytosis is more specific than phagocytosis

A

c. Pinocytosis is less specific than receptor mediated endocytosis

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5
Q

This is the most abundant and widely distribute tissue type in the body.

a. Epithelial
b. Connective
c. Muscle
d. Nervous

A

b. Connective

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6
Q

This tissue type is a covering and lining tissue. It also includes glands.

a. Epithelial
b. Connective
c. Muscle
d. Nervous

A

a. Epithelial

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7
Q

Epithelial tissue are found ________.

a. Attaching muscle to bone
b. Lining hollow organs
c. Under the skin providing padding
d. Within the brain

A

c. Under the skin providing padding

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8
Q

What is not true of epithelial cells?

a. They are bound together to form sheets
b. They are richly vascularized
c. They have a free surface
d. They regenerate readily

A

b. They are richly vascularized

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9
Q

Epithelial cells are specialized to ______.

a. Actively contract and produce many types of movements
b. Protect, support, and bind together other tissues
c. Receive stimuli and conduct electrical signals to all parts of the body
d. Secrete, filter, and absorb

A

d. Secrete, filter, and absorb

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10
Q

What is not true of connective tissues?

a. It contains both cells and noncellular, nonliving material
b. Its matrix is produced by the cells within the tissue
c. Its matrix contains fibers
d. All connective tissues contain elastic fibers

A

d. All connective tissues contain elastic fibers

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11
Q

This epithelial tissue has many cell layers. It forms the outer layer of the skin.

a. Stratified squamous
b. Stratified columnar
c. Pseudostratified columnar
d. Transitional

A

a. Stratified squamous

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12
Q

This tissue type is capable of changing its shape and stretching. It lines the urinary bladder and ureters.

a. Smooth muscle
b. Transitional epithelium
c. Stratified squamous epithelium
d. Dense irregular connective tissue

A

b. Transitional epithelium

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13
Q

This connective tissue consists of large round densely packed cells with the nucleus pushed to one side.

a. Adipose
b. Reticular
c. Hyaline Cartilage
d. Blood

A

a. Adipose

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14
Q

This connective tissue is made of hard calcified matrix and stores calcium and other minerals.

a. Dense irregular
b. Elastic cartilage
c. Bone (osseous)
d. Hyaline cartilage

A

c. Bone (osseous)

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15
Q

The cells found in the lacunae of cartilage are called _____.

a. Fibroblasts
b. Neutrophils
c. Osteocytes
d. Chondrocytes

A

d. Chondrocytes

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16
Q

This type of connective tissue is found under the epithelial, packaging organs, and surrounding capillaries.

a. Areolar
b. Dense elastic
c. Elastic cartilage
d. Reticular

A

a. Areolar

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17
Q

This tough, strong, connective tissue is found directly beneath the epithelial tissue of the skin. It is packaged with collagen fibers that run in all different directions.

a. Dense regular
b. Dense irregular
c. Dense elastic tissue
d. Bone (osseous) tissue

A

b. Dense irregular

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18
Q

This connective tissue is packed with parallel collagen fibers, attaches muscles to bone, and can withstand great stress when pulled in one direction.

a. Dense regular
b. Dense irregular
c. Areolar
d. Fibrocartilage

A

a. Dense regular

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19
Q

Select the statement about selective (or differential) permeability that is false:

a. It allows nutrients to enter the cell
b. It keeps cellular wastes inside the cells
c. It prevents undesirable wastes from entering the cells
d. It keeps valuable proteins inside cells

A

b. It keeps cellular wastes inside cells

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20
Q

Membrane transport may be passive or active. Select the active process from the list below.

a. Simple diffusion
b. Filtration
c. Osmosis
d. Phagocytosis

A

d. Phagocytosis

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21
Q

A membrane transport process is active if it requires _____.

a. A concentration gradient
b. A pressure difference
c. Energy provided by ATP
d. Kinetic energy of molecules

A

c. Energy provided by ATP

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22
Q

These molecules move through the lipid portion of the plasma membrane by simple diffusion.

a. CO2 and O2
b. Glucose
c. K+ and Ca2+
d. NA (+) and CL (-)

A

a. CO2 and O2

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23
Q

A solution is said to be isotonic if it contains _______.

a. More non penetrating solute particles than the interior of the cells
b. Fewer non penetrating solute particles than the interior of the cells
c. The same number of non penetrating solute particles as the interior of the cells.

A

c. The same number of non penetrating solute particles a the interior of the cells

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24
Q

The force that causes water and solutes to cross cells membranes by filtration is ______.

a. Concentration gradient
b. Hydrostatic pressure
c. Energy provided by ATP
d. Kinetic energy of molecules

A

b. Hydrostatic pressure

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25
Q

Which statement about vesicular transport is true?

a. Endocytosis transports particles/molecules out of the cell
b. Exocytosis transports particles/molecules into the cell
c. Phagocytosis is used to move cell wastes out of the cell
d. Pinocytosis is used to take liquids into a cell

A

d. Pinocytosis is used to take liquids into a cell

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26
Q

The addition of saturated fatty acids to the plasma membrane would ______ membrane fluidity, and the addition of unsaturated fatty acids would ______ membrane fluidity.

a. Increase, Decrease
b. Decrease, Increase
c. Increase, Increase
d. Decrease, Decrease

A

b. Decrease, Increase

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27
Q

A _______ in molecular size and a _______ in temperature result in an increased rate of diffusion.

A

Decrease

Increase

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28
Q

Active processes ________.

a. Included osmosis
b. Move fats and respiratory gases through cell membranes
c. Move substances against (up) a concentration gradient and/or electrical gradient
d. Require a hydrostatic pressure gradient

A

c. Move substances against (up) a concentration and/or electrical gradient

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29
Q

The transport of a certain molecule exhibits the following characteristics: i) the molecule moves down its concentration gradient, ii) at concentrations above a given level, the rate of transport does not increase, and iii) cellular energy is not required for transport. Name the type of transport this molecule is using.

A

Facilitated Diffusion

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30
Q

Negative feedback loops are far more common than positive feedback loops. Describe what a negative feedback loop is, and give one physiological example of when this occurs.

A

Negative feedback loop is when the body tries to counteract an external change.
Example: Control of body temperature

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31
Q

The matrix of bone contains 2/3 calcium salts and 1/3 collagen fibers and contains a small volume of ground substance. Explain, specifically, the physiological benefit of having this composition.

A

The matrix of bone being 2/3 calcium and 1/3 collagen makes the bone strong (calcium salts) but still flexible (collagen fibers) so that when you break a bone, it doesn’t shatter.

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32
Q

The form of homeostasis that humans maintain requires that we stay within a “range of living.” This is known as:

a. Feedforward equilibrium
b. Dynamic equilibrium
c. Their enzymes are unable to function very well in an acidic environment
d. Both a and c are correct

A

d. Dynamic equilibrium

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33
Q

When a cell is placed into a hypotonic solution, its volume will _____ because of the movement of _____.

a. Increase; water into the cell
b. Increase; solute into the cell
c. Decrease; water out of the cell
d. Decrease; solute out of the cell

A

a. Increase; water into the cell

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34
Q

In order for simple diffusion to occur, the only requirement is that a concentration gradient exists.

a. True
b. False

A

a. True

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35
Q

______, which is found in the plasma membrane of cells, is the only type of lipid that is referred to as being amphipathic.

A

Phospholipids

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36
Q

Briefly, please describe what is meant by the term amphipathic. In addition, specifically explain how this term applies to the type of lipid that you listed above.

A

Amphipathic means one side is polar/hydrophilic and one side is non-polar/hydrophobic.
This applies to phospholipids because they make up the plasma membrane.

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37
Q

Most animal cells contain 8.5% sucrose in the cytosol. If you placed red blood cells in a 5% sucrose solution, would this be considered isotonic, hypertonic, or hypotonic? What effect would this solution have on the red blood cells, and why might you observe this?

A

Hypotonic. It would cause the cell to go through hemolysis because the movement of solute into the cell would cause it to swell and potentially burst.

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38
Q

Parts of life arranged from most complex to simplest

A
Organisms
Organ system
Organ
Tissue
Cellular
Molecular
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39
Q

Which of the following would be LEAST likely to undergo SIMPLE diffusion across the plasma membrane?

a. Estrogen, a hydrophobic steroid hormone
b. A molecule of oxygen
c. A molecule of carbon dioxide
d. A hydrophilic calcium ion

A

d. A hydrophilic calcium ion

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40
Q

Within the human body, the vast majority of homeostasis is controlled by negative feedback loops.

a. True
b. False

A

a. True

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41
Q

The plasma membrane is often referred to as a “fluid-mosaic model.” Explain below why this is so

A

Because fluid is always in flux

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42
Q

Describe the effect that the addition of saturated phospholipids would have on the plasma membrane.

A

Saturated phospholipids would cause the plasma membrane to be more dense and rigid due to the phospholipids pushing together

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43
Q

During the maintenance of homeostasis, the _______ is responsible for carrying out a specific change within the body.

a. Effector
b. Integration center
c. Receptor
d. Stimulus

A

a. Effector

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44
Q

The ability of out bodies to predict upcoming changes in homeostasis and, as a result, sufficiently prepare for these changes, is known as _______.

A

Feed forward regulation

45
Q

Rate of transportation/Substrate concentration graph. Explain what you graphed data reveals about how membrane transport occurs.

A

Membrane transport occurs very quickly at first due to plenty of membrane proteins to carry things through the membrane, then starts to slow down the more you put in because you start running out of protein channels that are available. Channels also become saturated.

46
Q

In which of the following would the speed of action potential propagation be the fastest?

  1. Unmyelinated fiber of 10mm diameter
  2. Myelinated fiber of 10mm diameter
  3. Myelinated fiber of 20 mm in diameter
  4. Unmyelinated fiber of 20mm in diameter
  5. Myelinated fiber of 5mm in diameter
A
  1. Myelinated fiber of 20mm in diameter
47
Q

When the membrane potential reaches a charge of +30mV, which ion channels close (be specific)?

A

Voltage gated sodium channels

48
Q

When the membrane potential reaches a charge of +30 mV, which ion channels open?

A

Voltage gated potassium channels

49
Q

The “all-or-nothing” principle states that

  1. Every stimulus, regardless of strength, will produce identical action potentials
  2. Any stimulus great enough to bring the membrane to threshold will produce an identical action potential
  3. The greater the magnitude of the stimulus, the greater the strength of the action potential
  4. Any stimulus great enough to open ion channels on the membrane of a neuron will produce identical graded potentials
  5. None of the above are correct
A
  1. Any stimulus great enough to bring the membrane to threshold will produce an identical action potential
50
Q

In which of the following neuron types would you expect to only find in the brain and/or spinal cord?

  1. Bipolar neurons
  2. Unipolar neurons
  3. Afferent neurons
  4. Motor neurons
  5. Anaxonic neurons
A
  1. Anaxonic
51
Q

Monosynaptic reflexes are known for producing precise, refined reflex responses.

  1. True
  2. False
A
  1. False
52
Q

When a second IPSP arrives at a single synapse before the effects of the first IPSP have disappeared, which of the following occur?

  1. Spatial summation
  2. Temporal summation
  3. Depolarization
  4. Threshold is reached
  5. Action potential
A
  1. Temporal summation
53
Q

If voltage-gated sodium channels were unable to close their inactivation fares, the absolute refractory period would be

  1. Longer
  2. Shorter
  3. Not affected
A
  1. Longer
54
Q

Inhibitory post synaptic potentials

  1. Result in local depolarizations
  2. Result in local hyperpolarizations
  3. Increase membrane permeability to sodium ions
  4. Prevent the efflux of potassium ions
  5. Prevent the efflux of calcium ions
A
  1. Result in local hyperpolarizations
55
Q

Describe two mechanisms by which neurotransmitters are cleared from a synaptic cleft

A
  1. Binding to receptors on the post synaptic membrane

2. AChE breaks down AcH

56
Q

A neurotransmitter is released into a synapse and functions to prevent the postsynaptic neuron from firing an action potential. Th molecule is most likely binding to which type of receptor?

A

Chemically gated K+

57
Q

The following are steps involved in a typical neural reflex

  1. Activation of a sensory neuron
  2. Activation of a motor neuron
  3. Response by an effector
  4. Arrival of a stimulus and activation of a receptor
  5. Information processing
A
  1. Arrival of a stimulus and activation of a receptor
  2. Activation of a sensory neuron
  3. Information processing
  4. Activation of a motor neuron
  5. Response be an effector
58
Q

During an action potential, rapid depolarization is the result of which substance?

  1. Calcium
  2. Potassium
  3. Sodium
  4. Sodium channels
  5. More than one of the above are correct
A
  1. Potassium
59
Q

Temporal summation is unique in that it allows our neurons to summate IPSPs with EPSPs

  1. True
  2. False
A
  1. False.
    Why? Temporal summation is rapid and monosynaptic which means it only binds to one synapse and only IPSP or EPSP. Not both.
60
Q

The _____ nervous system is responsible for controlling the stimulation, or relaxation, of visceral organ tissues within our body.

A

Autonomic

61
Q

In order to have a resting membrane potential, you must have a semi-permeable membrane.

  1. True
  2. False
A
  1. True
62
Q

_______ are cells that are responsible for assuring that the environment is optimal for neurons of the peripheral nervous system to function properly.

A

Neuroglia Satellite

63
Q

Explain, in detail, why action potentials are able to travel only in one direction down an axon.

A

Action potentials only move in one direction down the axon because the action potential moved by segments and at the previous segment the voltage gated channels are already open or inactive (refractory periods)

64
Q

Define the term “membrane potential”

A

The electric potential of a membranes internal environment compared to its external environment

65
Q

The strength of a signal that is relayed by a neuron is determined primarily by which of the following?

  1. The peak of the action potential
  2. The degree of depolarization of the neuron
  3. The degree to which a neuron hyper polarizes
  4. The frequency of action potential firing
A
  1. The frequency of action potential firing
66
Q

_______ neurons carry information into the central nervous system

  1. Efferent
  2. Afferent
  3. Anaxonic
  4. Multipolar
A
  1. Afferent
67
Q

List and describe the two types of propagation used to carry an action potential down an axon.

A

Continuous–unmyelinated, every step along the way; slower

Saltatory–myelinated, jump-skips the internodes; faster

68
Q

Pain sensory receptors in your skin would most likely send action potentials using which type of propagation?

A

Saltatory

69
Q

It requires more than one EPSP in order for a neuron to reach threshold.

  1. True
  2. False
A
  1. True
70
Q

List two mechanisms used to establish the resting membrane potential.

A
  1. Leak channels

2. Sodium-potassium pump

71
Q

List two types of ion channels responsible for generating an action potential

A

Voltage gated sodium

72
Q

Name the neurotransmitter released at a cholinergic synapse

A

Acetylcholine

73
Q

Name the neurotransmitter known as a “feel good” neurotransmitter where low production is associated with a chronic depressive state.

A

Serotonin

74
Q

This neuroglia cell is responsible for the myelination of peripheral neuronal axons

  1. Ependymal cells
  2. Schwann cells
  3. Satellite cells
  4. Oligodendrocytes
A
  1. Schwann cells
75
Q

This neuroglia cell in the CNS maintains the blood brain barrier

  1. Oligodendrocytes
  2. Schwann cells
  3. Astrocyte
  4. Ependymal cells
A
  1. Astrocyte
76
Q

List two mechanisms that describe how a neuromodulator might affect the method in which a neuron sends or receives a message at a neural synapse.

A
  1. Number of receptors

2. Can block the receptor

77
Q

Given the fact that compact bone tissue does not readily allow for diffusion of gases and nutrients, which of the following structures are utilized by osteocytes to connect lacunae with each other for nutrient exchange.

a. Marrow cavity
b. Canaliculi
c. Matrix
d. Lamellae

A

b. Canaliculi

78
Q

Within skeletal muscle, one would expect to find the endomysium directly surrounding

a. The entire skeletal muscle
b. Muscle Fascicles
c. Muscle fibers
d. Sarcomeres

A

c. Muscle fibers

79
Q

Which of the following acts as an ATPase during the contraction cycle of skeletal muscle?

a. Troponin
b. Tropomyosin
c. The tail portion of myosin
d. The head portion of myosin
e. G and F-actin molecules

A

d. The head portion of myosin

80
Q

Bone is enclosed by an outer covering known as the ______.

A

Periosteum

81
Q

The part of the osteon where a capillary and venule run to control blood supply to the osteon is the _________.

A

Central Canal

82
Q

Mature bone cells that make up most of the population of cells in bone tissue are called ___________

A

Osteocytes

83
Q

The cell type found in bone that is responsible for removing and recycling bone matrix are ________.

A

Osteoclast

84
Q

Describe two differences between compact and spongy bone.

A
Compact:
1. Found in the shaft of long bones
2. Withstand force from one direction
Spongy:
1. Less dense than compact bone
2. Withstand stress from wide range of directions
85
Q

Unlike compact bone, spongy bone is not very strong. Describe where you might find spongy bone and list one reason why spongy bone is an advantage over compact bone.

A

Top/bottom of long bone (epiphyseal); withstand stress for wide range of directions

86
Q

The primary difference between endochondral and intramembranous ossification is that

a. Endochondral ossification occurs prior to puberty, while intramembranous ossification occurs following the onset of puberty
b. Intramembranous ossification occurs prior to puberty, while endochondral ossification occurs following the onset of puberty
c. Endochondral ossification begins with a cartilaginous template, while intramembranous ossification does not
d. Intramembranous ossification beings with a cartilaginous template, while endochondral ossification does not.

A

c. Endochondral ossification begins with cartilaginous template while intramembanous ossification does not.

87
Q

The outermost layer of compact bone where bones grow in diameter is called the ________.

a. Lacunae
b. Trabeculae
c. Osteon
d. Central Canal

A

a. Lacunae

88
Q

______ is a muscle structure composed of sarcomeres lined up one after the other

a. Fascicles
b. Fibers
c. Myofibrils
d. Perimysium
e. Epimysium

A

c. Myofibrils

89
Q

______ are remnants of old osteons that have been rearranged to fill gaps between newer osteons

A

Interstitial Lamellae

90
Q

With regards to bones, define appositional growth

A

Appositional growth is the bone growing in diameter

91
Q

During endochondral ossification, the formation of bone in the secondary ossification is incomplete. Describe why this is significant for bone growth from childhood to full adult height.

A

This is significant for bone growth from childhood to full adult because it allows for puberty to occur. After puberty occurs, the bone will then complete its growth

92
Q

During a typical skeletal muscle contraction, think filaments

a. Move towards to z lines
b. Move in a way that decreases the zone of overlap
c. Pull on thick filaments to increase the zone of overlap
d. Are pulled by thick filaments to decrease the zone of overlap
e. Collectively move towards the m line

A

e. Collectively move toward the m line.

93
Q

Within skeletal muscle, the active sites are present on molecules of

a. Tropomyosin
b. Actin
c. Troponin
d. The myosin tail
e. The myosin tail

A

b. Actin

94
Q

During a skeletal muscle twitch, if the resting length of the muscle fiber was increased, how would this affect the ability of that muscle fiber to produce tension?

a. It would decrease the amount of tension produced by the muscle fiber
b. It wold increase the amount of tension produced by the muscle fiber
c. It would not change the amount of tension produced by the muscle fiber

A

a. It would decrease the amount of tension produced by the muscle fiber.

Why?
If the resting length of muscle fibers was increased past its normal length, that would mean there would be a pulled/stretched muscle, which is weaker and produced less tension. (Zone of overlap is reduced)

95
Q

The type of bone that is adapted to withstand stress from a wide range of directions is ______ bone.

a. Spongy
b. Compact
c. Irregular
d. Flat
e. Lamellar

A

a. Spongy

96
Q

_______ is a period of skeletal muscle contraction without any time for relaxation.

A

Tetanus

97
Q

Acetylcholine receptors are present on the sarcolemma. When they bind acetylcholine molecules, they cause the muscle fiber to depolarize which results with the release of which ion from the sarcoplasmic reticulum?

a. Potassium
b. Calcium
c. Magnesium
d. Sodium

A

b. Calcium

98
Q

The shaft region of a long bone is also referred to as the _______.

A

Diaphysis

99
Q

The head region of a long bone is also referred to as the _______.

A

Epiphysis

100
Q

Name the hormone secreted in response to decreased levels of calcium in the blood.

A

Parathyroid hormone

101
Q

_________ is the connective tissue found in skeletal muscle that surround individual muscle fascicles

A

Perimysium

102
Q

List and describe the three different types of muscle tissue and their key features (physical appearance, number of nuclei, ability to divide, involuntary/voluntary control)

A
  1. Skeletal: Attaches to the skeleton, voluntary control
  2. Cardiac: Helps the heart. Involuntary control
  3. Smooth: Non striated, uni-nuclear, divide, involuntary
103
Q

List 3 functions of bones

A

Strength
Structure
Storage

104
Q

List the two components of a motor unit

A

Muscle fiber

Motor neuron

105
Q

Which type of motor unit is associated with strength and power?

A

Large muscular

106
Q

_______ stores oxygen in muscle tissue for immediate use in muscle tissue in response to short intense bursts of exercise, but quickly (6 seconds) runs out of its stores

A

Myoglobin

107
Q

Describe two main differences in using anaerobic fermentation for short term energy and aerobic respiration for long term energy in muscle tissues

A
Anaerobic
1. No oxygen needed
2. Runs through supply quickly (6-10ish seconds)
Aerobic
1. Oxygen needed 
2. Used for longer exercises
108
Q

During a time of continual muscle contraction, muscle tension is maintained though a process referred to as Asynchronous Motor Unit Recruitment. Define this term and give one example of why it is helpful.

A

Asynchronous Motor Recruitment uses different motor units at different times while a muscle is contracted to keep the muscle tension strong. This is helpful if you are doing wall sits in gym class and you have to use a muscle for a long period of time.

109
Q

How does a muscle contract and relax?

A
  1. Acetylcholine is released at neuromuscular junction which produces an action potential
  2. Electrical impulse travels down T-Tubules– triggering calcium release into sarcoplasmic reticulum
  3. Calcium binds to troponin - Displacing tropomyosin - activating the myosin head. It then binds to actin forming a cross bridge, myosin performs a power stroke = myosin head moves closer to M-line
  4. Sarcomere shortens = Muscle tension
  5. ACH is broken down = end action potential gradient
  6. Sarcoplasmic reticulum reabsorbs calcium
  7. Tropomyosin returns to normal position - covering active sites on actin
  8. Contraction ends and muscle relaxes