Midterm #1 (Units 1-3) Flashcards

1
Q

Define: physiology

A

the science of the functioning of living organisms

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2
Q

Define: Homeostasis

A

a state of body equilibrium or stable internal environment of the body. (maintenance of a stable internal environment)

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3
Q

What is blood maintained at?

A

Blood is maintained at a relatively constant composition to provide the stable conditions necessary for cell function.

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4
Q

T or F: The external environment is variable?

A

True

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5
Q

T of F: The internal environment must be stable otherwise it will not work.

A

True

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6
Q

List the levels of structural organization:

A

1) Chemical level
2) Cellular level
3) Tissue level
4) Organ level
5) System level
6) Organismal Level

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7
Q

What is blood categorized as?

A

blood is categorized as connective tissue

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8
Q

Define: Homeostatic imbalance

A

A disturbance in homeostasis resulting in stress or disease.

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9
Q

Which structure is a single heaviest organ in the mammalian body?

a) Liver
b) Spleen
c) Pelvic Bones
d) Brain
e) Other

A

e) Other - the correct answer is “Skin”

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10
Q

How is the internal environment separated from the external environment?

A

By the skin

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11
Q

Who coined the term”homeostasis”?

A

Walter Cannon

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12
Q

____ generated by metabolism is lost through the skin and mucous membranes.

A

Heat

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13
Q

______ are the portals for the movement of chemicals from the environment into the organism and vice versa.

A

Specialized organ system

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14
Q

What does homeostatic control rely on?

A
  • Constant monitoring of the composition of blood
  • Responding to changes in blood
  • Most systems operate in a negative feedback manner
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15
Q

The body communicated through ____ and _______ control systems.

A

neural and hormonal

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16
Q

What does the receptor (sensor + integrator) do?

A

Responds to changes in the environment and sends information to control center.

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17
Q

What does the control center do?

A
  • Determines set point
  • Analyzes information
  • Determines appropriate response.
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18
Q

What does the effector do?

A

Provides a means for response to the stimulus.

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19
Q

What does negative feedback do?

A
  • Includes most homeostatic mechanisms
  • Shuts off the original stimulus, or reduces the intensity
  • Works like a household thermostat.
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20
Q

What does positive feedback do?

A

Increases the original stimulus to push the variable farther. (only happens in blood clotting, before ovulation, and during the birth of a baby.)

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21
Q

Define: Anatomy

A

Study of the parts of the structure and shape of the body and its parts.

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22
Q

What is physiology the study of?

A

Physiology is the study of the organ systems that maintain homeostasis. ( is the study of the processes that organ systems use to carry out their function.)

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23
Q

What are elements?

A
  • fundamental units of matter
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24
Q

96% of the body is made up of what four elements?

A
  • Carbon (C)
  • Oxygen (O)
  • Hydrogen (H)
  • Nitrogen (N)
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25
Q

What are atoms?

A
  • building blocks of elements
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26
Q

What is the most important acid for food breakdown/digestion?

A

Hydrochloric acid

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27
Q

_______ compounds:

  • Lack carbon
  • Tend to be simpler compounds
  • Include water, salts, and some acids and bases
A

Inorganic

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28
Q

_______ compounds:

  • Contain carbon
  • Most are covalently bonded
  • Include carbohydrates, lipids, proteins, nucleic acids, ATP
A

Organic

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29
Q

What is the most abundant inorganic compound in the body?

A

Water

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30
Q

All physiological processes take place in an ______ medium.

A

Aqueous

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31
Q

What are the vital properties of the inorganic compound water:

A
  • High heat capacity
  • Polar/Solvent properties
  • Chemical reactivity
  • Cushioning
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32
Q

Which inorganic compound easily dissociates into ions in the presence of water into electrically charged currents?

A

Salts (electrolytes)

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33
Q

A balance of _____ is essential for all physiological processes.

A

electrolytes

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34
Q

What is the neutralization reaction?

A

Acids and bases react to form water and a salt

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35
Q

____ release hydrogen ions and are proton donors.

A

Acids

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36
Q

____ release hydroxyl ions and are proton acceptors.

A

Bases

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37
Q

A pH below 7 is:

A

Acidic

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38
Q

A pH above 7 is:

A

Basic

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39
Q

A pH of 7 is:

A

Neutral

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40
Q

All life forms are made up of molecules that are _______.

A

Carbon based

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41
Q

Carbohydrates consist of:

A
  • carbon
  • hydrogen
  • oxygen
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42
Q

What are the three major categories of lipids?

A
  • Fats and oils (used to store energy)
  • Cholesterol (essential for the production of steroid hormones)
  • Phospholipids (major component of cell membranes)
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43
Q

The major component of fats and oils is a class of lipids called _________.

A

triglycerides (three molecules of fatty acids are combined with one molecule of glycerol)

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44
Q

Approximately ___% of total body cholesterol is synthesized within body tissues; only ___% is obtained from diet.

A

85%, 15%

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45
Q

Phospholipids contain _____ fatty acids instead of _____.

A

two, three

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46
Q

_______ accounts for over half of the body’s organic matter.

A

Proteins

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47
Q

What do proteins do?

A
  • Provide construction materials for body tissues

- Play a vital role in cell function

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48
Q

What do proteins contain?

A
  • Carbon
  • Oxygen
  • Hydrogen
  • Nitrogen
  • Sometimes sulfur
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49
Q

What are proteins built from?

A

Amino Acids ( 20 different amino acids make up tissue proteins.

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50
Q

What is the amino acid structure of protein?

A
  • Contain an amine group
  • Contain an acid group
  • Vary only by R groups
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51
Q

______ protein chains undergo conformational changes, including the formation of helices, and parallel chains within the molecule, and further folding to make the functional tertiary protein structure.

A

Primary

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52
Q

_____ structure is the number and arrangement of multiple folded protein subunits in a multi-subunit complex.

A

Quaternary

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53
Q

Proteins comprise over ___% of the body

A

50%

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54
Q

______ are related to proteins, but the chains of amino acids are much shorter.

A

Peptides

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55
Q

ATP is made in cell organelles called _________.

A

Mitochondria

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56
Q

Adenosine triphosphate (ATP) is composed of a nucleotide built from:

A
  • ribose sugar
  • adenine base
  • three phosphate groups
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57
Q

How is energy released?

A

by breaking a high energy phosphate bond

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58
Q

How is ATP replenished?

A

by oxidation of food fuels

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59
Q

What are the uses of ATP?

A
  • Drive energy-absorbing chemical reactions
  • Drive transport of certain solutes across cell membrane
  • Activate contractile proteins to perform mechanical work
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60
Q

Damage to the _____ may result in the disruption of normal cell processes.

A

DNA

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61
Q

The three varieties of RNA are:

A
  • messenger (mRNA)
  • transfer (tRNA)
  • ribosomal (rRNA)
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62
Q

____ are groups of cells that are similar in structure and function.

A

tissues

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63
Q

Cells that connect body parts are:

A
  • fibroblasts

- erythrocytes

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64
Q

Cells that cover and line body organs are:

A

Epithelial cells

65
Q

Cells that move organs and body parts are:

A

Skeletal muscle cells

66
Q

Cells that store nutrients are:

A

Fat cells (adipose cells)

67
Q

Cells that fight disease are:

A

Macrophage (white blood cells)

68
Q

Cells that gather information and control body functions are:

A

Nerve cells

69
Q

Cells of reproduction are:

A

Sperm

70
Q

What are the three main regions of a cell?

A
  • Plasma membrane
  • Cytoplasm
  • Nucleus
71
Q

_____ are finger-like projections that increase surface area for absorption.

A

Microvilli

72
Q

List three cell junctions:

A
  • Tight junctions (Impermeable)
  • Desmosomes (Anchoring)
  • Gap junctions (Communicating)
73
Q

_____ junctions seal cells together in an epithelium in a way that prevents even small molecules from leaking from one side of the sheet to the other.

A

Occluding (tight)

74
Q

______ junctions mechanically attach cells to their neighbours or to the extracellular matrix.

A

Anchoring (desmosomes)

75
Q

______ junctions mediate the passage of chemical or electrical signals from one interacting cell to its partner.

A

Communicating (gap)

76
Q

Ribosomal endoplasmic reticulum (RER) is the site of _________.

A

Protein synthasis

77
Q

What is cytoplasm?

A

The liquid material outside the nucleus and inside the plasma membrane.

78
Q

What are the 4 steps of protein synthesis?

A
  1. Protein is synthesized on ribosome
  2. Protein folds into functional shape
  3. Protein is packaged into vesicle
  4. Vesicle buds off and moves to Golgi apparatus
79
Q

Golgi apparatus is the site of:

A

protein packaging into granules or vesicles

80
Q

_____ vesicles contain proteins that will be secreted by the cell

A

Secretory

81
Q

The smooth endoplasmic reticulum (SER) is the site of synthesis of _____.

A

Steroids

82
Q

The two basic methods of membrane transport are:

A
  • Passive processes (no energy is required)

- Active processes (Cell must provide metabolic energy [ATP])

83
Q

List the 4 passive processes:

A
  • Simple Diffusion
  • Osmosis
  • Facilitated diffusion
  • Filtration
84
Q

What happens in simple diffusion?

A
  • Particles tend to distribute themselves evenly within a solution
  • Movement is from high concentration to low concentration
85
Q

What happens in osmosis?

A
  • Simple diffusion of water

- Go from dilute to more concentrated solution

86
Q

Facilitated diffusion involved transporting liquid-insoluble and large substances. T or F

A

True

87
Q

What is filtration?

A

Water and solutes are forced through a membrane by fluid, or hydrostatic pressure.

88
Q

What do solute pumps transport?

A
  • Amino acids
  • some sugars
  • ions
89
Q

What are the two forms of bulk (vesicular) transport?

A
  • Endocytosis

- Exocytosis

90
Q

________ is the movement of substances into a cell.

A

Endocytosis (absorption)

91
Q

_______ is the movement of substances out of a cell.

A

Exocytosis (to expel)

92
Q

List the two types of endocytosis:

A
  • Phagocytosis (solid matter)

- Pinocytosis (absorption of water soluble solutions)

93
Q

________ occurs when a stimulus causes Na+ channels in the membrane (normally closed) to open, and Na+ rapidly enters the cell down its concentration gradient.

A

Depolarization

94
Q

Propagation of depolarizations of the membrane =

A

action potential

95
Q

______ of the membrane occurs within 1-3 milliseconds, and the resting membrane potential is reinstated.

A

Repolarization

96
Q

The plasma membrane at rest is ________.

A

Polarized

97
Q

ATP provides the energy for active transport of materials across cell membranes; which of the following is (are) true concerning the process of active transport?

a. it results in the unequal distribution of ions on the two sides of the membrane
b. it contributes to the development of an electrical potential across the membrane
c. it actively moves amino acids across membranes d. it permits the transport of some sugars across membranes
e. all of the above are correct

A

E

98
Q

The unequal distribution of sodium and potassium ions on the two sides of the plasma membrane of a cell is a factor in establishing an electrical potential difference across the membrane; this charge difference is called a. the resting membrane potential b. the action potential c. the generator potential d. the depolarization potential e. none of the above

A

A

99
Q

Cholesterol

a. is a form of lipid
b. is largely obtained from the diet
c. is of no physiological value
d. is essential for the production of steroid hormones
e. a) and d) are correct

A

E

100
Q

The building blocks of proteins are

a. amino acids
b. nucleotides
c. salts
d. ribose
e. amines

A

A

101
Q

A tissue is an aggregate of similar differentiated

a. cells
b. functional units
c. organisms
d. organ systems
e. organs

A

A

102
Q

Physiology is the biological science that is most concerned with which of the following characteristics of living organisms?

a. structure
b. chemistry
c. disease
d. function
e. heredity

A

D

103
Q

The kidneys excrete urea in the urine because the body needs to remove the nitrogenous waste products of protein metabolism. This statement is an example of

a. anatomical fact
b. incorrect statement, because the kidneys do not remove urea
c. physiological explanation of a function d. state of disease for kidney anatomy and physiology
e. none of the above

A

C

104
Q

Cells in the human body perform specific functions. Some cover body surfaces while others contract or send signals. This is an example of cell a. differentiation

b. intelligence
c. growth
d. degeneration
e. metabolism

A

A

105
Q

The class of differentiated cells whose specialized functions include the movement of molecules from one compartment to another across this layer of cells is known as

a. cartilage
b. epithelial
c. muscle
d. nerve
e. gametes

A

B

106
Q

Collagen, a major protein formed by many types of connective tissue cells, is located

a. in the extracellular fluid outside connective tissue cells
b. inside connective tissue cells
c. in mitochondria of all connective tissue cells
d. inside red blood cells
e. inside white blood cell

A

A

107
Q

The nephrons of the kidney are its

a. atoms
b. functional units
c. hormones
d. organs
e. organ systems

A

B

108
Q

Select the incorrect association.

a. endocrine system – removal of waste products from the blood b. immune system – defense against foreign invaders
c. digestive system – absorption of nutrients from the diet
d. nervous system – regulation and coordination of activities e. respiratory system – exchange of gases

A

A

109
Q

Pick the body response illustrating homeostasis.

a. blood pressure continues to get higher and higher
b. blood sugar drops during starvation
c. body temperature rises during fever
d. the acidity of the extracellular fluid remains the same after a diet changes
e. the person slips into irreversible shock

A

D

110
Q

Assume that 35% of a person’s body weight is extracellular fluid. The percentage of body weight contributed by the intracellular fluid is closest to

a. 3
b. 25
c. 45
d. 50
e. 60

A

C

111
Q

The percentage of body weight contributed by atoms of carbon and oxygen is about

a. 1
b. 9
c. 26
d. 35
e. 89

A

E

112
Q

A compound will not dissolve in water if it is

a. hydrophilic
b. hydrophobic
c. ionic
d. polar
e. inorganic

A

B

113
Q

A solution with a pH of 12 is

a. neutral
b. slightly alkaline
c. slightly acidic
d. very alkaline
e. very acidic

A

D

114
Q

A factor that will not vary appreciably with body size in adults is

a. acidity (pH) of the extracellular fluid
b. body weight
c. cell number
d. percentage of body fat e. volume of blood

A

A

115
Q

Carbohydrate molecules contain numerous

a. amino groups, -NH2
b. carboxyl groups, -COOH
c. hydroxyl groups, -OH
d. nitrogen atoms
e. phosphorus atoms

A

C

116
Q

Glucose is a(n)

a. amino acid
b. fatty acid
c. lipid
d. monosaccharide
e. protein

A

D

117
Q

Starch and glycogen (glycogen is used to store chemical energy in the body) are

a. polylipids
b. polynucleotides
c. polypeptides
d. polypeptones
e. polysaccharides

A

E

118
Q

Glycerol is an organic molecule that makes up one of the components of: a. fats

b. carbohydrates
c. nucleic acids
d. starch
e. proteins

A

A

119
Q

Lipids are hydrolyzed to

a. amino acids and fatty acids
b. amino acids and glycerol c. glycerol and monosaccharides
d. fatty acids and glycerol e. monosaccharides and polysaccharides

A

D

120
Q

The class of organic molecules characterized by their insolubility in water is the

a. carbohydrates
b. ions
c. nucleic acids
d. lipids
e. amino acids

A

D

121
Q

The molecule illustrated below is a(n): CH3-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-COOH

a. amino acid
b. fatty acid
c. monosaccharide
d. nucleotide
e. polysaccharide

A

B

122
Q

Nitrogen atoms are found in greatest abundance in a. carbohydrates

b. lipids
c. phospholipids
d. proteins
e. steroids

A

D

123
Q

Which of the following elements is absent in protein molecules?

a. carbon
b. hydrogen
c. magnesium
d. nitrogen
e. oxygen

A

C

124
Q

Which of the following statements is correct?

a. All proteins are 20 amino acids long.
b. Many more than 20 amino acids have been discovered throughout protein structure.
c. Only 4 different amino acids exist among all proteins.
d. Only 20 different amino acids have been found in protein molecules synthesized by living organisms.
e. Every protein molecule contains 20 different amino acids.

A

D

125
Q

The subunits of nucleic acids are

a. amino acids
b. amines
c. bases
d. monosaccharides
e. nucleotides

A

E

126
Q

RNA differs from DNA because

a. it contains more than 4 different nucleotide bases b. it is not a nucleic acid
c. is it usually a double-stranded molecule
d. its sugar component is deoxyribose
e. one of its building-block bases is uracil

A

E

127
Q

A short DNA double helix consists of 9 base pairs. Four of them are G-C. The total number of thymine bases in this helix is

a. 1
b. 5
c. 10
d. 15
e. 18

A

B

128
Q

Each is a function of plasma membranes except

a. anchor a variety of proteins
b. detect chemical messengers arriving at cell surface
c. link adjacent cells together
d. regulate passage of substances in and out of the cell
e. synthesize chromosomal DNA for passage to the nucleus

A

E

129
Q

Desmosomes

a. are membrane junctions that hold adjacent cells together in tissues that are subject to considerable stretching.
b. are membrane junctions that prevent the diffusion of substances through the extracellular spaces between epithelial cells.
c. consist of protein channels that link two cells together and thus allow small molecules and ions to diffuse directly from one cell to the other. d. eliminate the amount of extracellular space between adjacent cells.
e. provide large spaces between cells for molecule transport.

A

A

130
Q

Which of the following cell organelles plays an essential role in energy production?

a. nucleus
b. Golgi apparatus
c. smooth endoplasmic reticulum
d. lysosome
e. mitochondrion

A

E

131
Q

Which of the following microstructures is not located in the cytoplasm? a. chromosome

b. endoplasmic reticulum c. lysosome
d. mitochondrion
e. secretory vesicle

A

A

132
Q

The Schwann cell forms a myelin sheath around the a. axon

b. nodes of Ranvier
c. dendrites
d. cell body
e. nucleus

A

A

133
Q

The neuron processes that normally receive incoming stimuli are called

a. neurolemmas
b. dendrites
c. satellite cells
d. axons
e. Schwann cells

A

B

134
Q

Immediately after an action potential is propagated, which one of the following ions rapidly diffuses out of the cell into the tissue fluid?

a. sodium
b. potassium
c. calcium
d. chloride
e. magnesium

A

B

135
Q

The diffusion of sodium ions into a neuron causes it to immediately experience

a. an action potential
b. resting membrane potential
c. depolarization
d. a nerve impulse
e. repolarization

A

C

136
Q

Which one of the following is the correct sequence of events that follows a threshold potential?

  1. the membrane becomes depolarized
  2. sodium channels open and sodium ions diffuse inward
  3. the membrane becomes repolarized
  4. potassium channels open and potassium ions diffuse outward while sodium is actively transported out of the cell
    a. 3, 2, 4, 1
    b. 1, 2, 4, 3
    c. 4, 1, 3, 2
    d. 2, 1, 3, 4
    e. 2, 1, 4, 3
A

E

137
Q

The _____________ is part of the autonomic nervous system and it regulates body temperature, water balance and metabolism. a. midbrain

b. cerebrum
c. medulla oblongata
d. pons
e. hypothalamus

A

E

138
Q

Nerve cell bodies outside the brain are called

a. tracts
b. nerves
c. ganglia
d. nuclei
e. tracts or ganglia

A

C

139
Q

The subarachnoid space lies directly between thea. arachnoid mater and dura mater

b. arachnoid mater and pia mater
c. arachnoid mater and cerebrum
d. skull and arachnoid mater
e. arachnoid mater and cerebellum

A

B

140
Q

Which one of the following is the correct sequence in connective tissue sheaths, going from outermost to innermost layer?

a. perineurium, epineurium, endoneurium b. epineurium, endoneurium, perineurium
c. epineurium, perineurium, endoneurium
d. endoneurium, epineurium, perineurium e. perineurium, endoneurium, epineurium

A

C

141
Q

Afferent nerves are called __________, and motor nerves are called __________.

a. mixed nerves, sensory nerves
b. efferent nerves, sensory nerves
c. sensory nerves, efferent nerves
d. peripheral nerves, cranial nerves
e. cranial nerves, peripheral nerves

A

C

142
Q

Which of the following is a characteristic of the parasympathetic nervous system?

a. the cell bodies of most postganglionic neurons are located in ganglia situated near the spinal cord
b. the nerve fibres emerge from the brain and the sacral portion of the spinal cord
c. the neurotransmitter substance released form the postganglionic neurons binds to alpha and beta receptors on effector cells
d. the postganglionic neurons innervate skeletal muscles
e. all of the above

A

B

143
Q

Norepinephrine is the neurotransmitter released at most postganglionic nerve terminals in the

a. parasympathetic nervous system
b. somatic nervous system c. sympathetic nervous system
d. a and c
e. b and c

A

C

144
Q

The rising phase of an action potential is due to a. an increase in the electrogenic potential produced by increased activity of the sodium-potassium pump

b. decreased potassium permeability
c. decreased sodium permeability
d. increased potassium permeability
e. increased sodium permeability

A

E

145
Q

At a chemical synapse,

a. a single action potential arriving at the presynaptic terminal will always induce the action potential in a single postsynaptic neuron.
b. an excitory neurotransmitter will act upon calcium channels in the postsynaptic membrane.
c. inhibition of the active re-uptake of neurotransmitter molecules by the presynaptic terminal will prolong the duration of the postsynaptic potential.
d. the release of neurotransmitter from the presynaptic terminal is triggered by a rise in cytosolic sodium concentration.
e. all of the above

A

C

146
Q

Which of the following types of muscle is striated?

a. cardiac muscle
b. skeletal muscle
c. smooth muscle
d. a and b
e. a and c

A

D

147
Q

Troponin and tropomyosin are proteins associated with

a. neuromuscular junction b. sarcolemma
c. sarcoplasmic reticulum d. thick filaments
e. thin filaments

A

E

148
Q

Muscles are connected to bones by

a. cartilage
b. ligament
c. muscle fibers
d. tendons
e. skin

A

D

149
Q

Myosin filaments in the sarcomere are anchored by

a. M line
b. Z line
c. H zone
d. I zone
e. A band

A

A

150
Q

The thick filaments in skeletal muscle fibre

a. are located in the A band
b. are attached to the Z lines
c. contain the contractile protein actin
d. contain troponin and tropomyosin
e. all of the above

A

A

151
Q

The function of the transverse tubules (T tubules) in the skeletal muscle is to

a. actively transport calcium ions out of the cytosol to produce muscle relaxation
b. block the binding of myosin heads to actin filaments
c. provide a path for extracellular calcium ions to diffuse into the interior of the muscle fibre
d. provide a path for a rapid conduction of the muscle action potential into the interior of the muscle
e. store calcium ions that can be released into the cytosol during muscle excitation

A

D

152
Q

Neurotransmitter released at a skeletal muscle junction is

a. acetylcholine
b. histamine
c. noradrenaline
d. adrenaline
e. none of the above

A

A

153
Q

Which of the following will increase the force and duration of skeletal muscle contraction?

a. increasing the concentration of ATP in the muscle fibre
b. increasing the concentration of cytosolic calcium ions above the peak concentration reached after a single action potential
c. initiating a second and subsequent action potentials at the point when the twitch has reached a peak of its contraction
d. stretching a muscle beyond its optimal length e. all of the above

A

C

154
Q

Which of the following are not present in smooth muscles?

a. sarcomeres
b. transverse tubules
c. intercalated discs
d. Z discs
e. all of the above

A

E

155
Q

Which of the following is never present in smooth muscle cells?

a. actin
b. myosin
c. action potentials
d. gap junction
e. sarcomeres

A

E

156
Q

What is the name of the protein that forms the thin filaments that are involved in contraction?

a. myosin
b. globulin
c. actin
d. myofibril
e. fascicle

A

C

157
Q

The connective tissue layer that wraps around a muscle fibre is

a. perimysium
b. endomysium
c. epimysium
d. perineurium
e. epineurium

A

B

158
Q

Which of the following does not occur during a muscle contraction?

a. the H zone disappears b. the Z discs shorten
c. the myofilaments shorten
d. the sarcomere shortens e. the A band disappears

A

E

159
Q

A myofibril is

a. wrapped by the endomysium
b. made up of many fascicles
c. synonymous with a muscle fiber
d. a smaller division than myofilaments
e. made up of sarcomeres

A

E