midterm anatomy and phys Flashcards
(296 cards)
1
Q
The activities of an anatomist consist of ______, whereas those of a physiologist consist of _____.
A
observing body parts; studying functions of body parts
2
Q
Which of the following is not true of organelles?
A
A.They carry on specific activities. B.They are only in cells of humans. C.They are composed of aggregates of large molecules. D.They are found in many types of cells. Answer B
3
Q
Metabolism is defined as _____.
A
all the chemical reactions occurring in an organism that support life.
4
Q
Homeostasis is the
A
tendency of the body to maintain a stable internal environment.
5
Q
A serous membrane consists of a
A
layer of simple squamous epithelium and a thin layer of areolar tissue.
6
Q
In negative feedback mechanisms changes away from the normal state
A
stimulate changes in the opposite direction.
7
Q
Signs of aging at the cellular level are
A
impaired cell division and the ability to break down and recycle worn cell parts
8
Q
Which of the following lists best illustrates the idea of increasing levels of complexity?
A
Organelles, cells, tissues, organs, organ systems
9
Q
The anatomical term that indicates a structure close to the surface is
A
superficial .
10
Q
When the body is placed in the anatomical position, which of the following is not true?
A
A.The head is facing to the front.
correct B. The palms are facing backward.
C. The body is erect.
D. The upper limbs are at the sides
11
Q
The elbow is distal to the wrist
A
False
12
Q
In all organisms, the basic unit of structure and function is
A
the cell
13
Q
The thoracic cavity lies _____________ the abdominopelvic cavity.
A
superior to
14
Q
The ears are lateral to the eyes.
A
True
15
Q
Which of the following characteristics of life and their descriptions are correct?
A
Circulation-the movement of substances in body fluids
16
Q
The ability of an organism to sense and react to changes in its body illustrates
A
responsiveness
17
Q
The oral, nasal, orbital, and middle ear cavities are in the dorsal cavity
A
false
18
Q
Kidneys are part of the lymphatic system.
A
False
19
Q
Chemistry is important to the study of physiology because
A
A. the foods that we eat are chemicals.
B. body functions depend on cellular functions that reflect chemical changes.
C. chemical reactions enable our bodies to extract energy from nutrients.
D. all of the above
Answer D
20
Q
Which of the following substances is an element?
A
Iron
21
Q
The atoms of the isotopes of a particular element vary in the number of
A
neutrons
22
Q
Which of the following groups of elements account for more than 95% of the human body by weight?
A
Carbon, hydrogen, oxygen, nitrogen
23
Q
The number of protons in an atom of an element always equals its atomic weight.
A
False
24
Q
An electrolyte ionizes in water.
A
True
25
A person with alkalosis has a blood pH less than 7.3
False
26
Which of the following is the most abundant inorganic substance in the body?
Water
27
An organic compound always contains
carbon and hydrogen
28
A chemical reaction in which parts of different molecules trade positions is a(n)
Exchanged reaction
29
In a covalent bond
atoms share a pair or more of electrons.
30
The formula H2O refers to
A molecule that contains two hydrogen atoms and one oxygen atom
31
The symbol Na+ represents a sodium atom that has lost an electron
True
32
The three major parts of a cell are
the nucleus, cytoplasm, and cell membrane
33
Lipids
A. are insoluble in water.
B. include phospholipids, cholesterol, and fats.
C. contain C, H, and O, but with proportionately less oxygen than in carbohydrates.
correct D.all of the above.
34
Which of the following is characteristic of carbohydrates?
A. They contain C, H, O, with twice as many hydrogen as oxygen atoms.
B. They provide much of the energy that the cell requires.
C.They include sugars and starches.
correct D.all of the above.
35
Which of the following groups of compounds is hydrophobic?
Lipids
36
The difference in hydrogen ion concentration between solutions with pH 4 and pH 5 is
ten fold
37
The major components of the cell membrane are
lipids and proteins
38
The secondary structure of a protein molecule is the result of
hydrogen bonds
39
Consider the following list of commonly found items and their pH values:Which of the choices includes all acids?
Vinegar, grapes, tomatoes, and coffee
40
If the concentration of glucose in the water outside of a cell is higher than the concentration inside,
water will leave the cell by osmosis
41
Nucleic acids are
composed of building blocks called nucleotides
42
If a red blood cell is placed in a hypotonic solution,
the cell will swell and may eventually burst.
43
In phagocytosis
a cell membrane engulfs solid particles.
44
Stages of the cell cycle unfold in the following order:
interphase, mitosis, cytoplasmic division, differentiation
45
All cell types divide at the same rate
false
46
A person with alkalosis has a blood pH less than 7.3
false
47
A selectively permeable membrane
allows some substances to pass through and excludes others
48
Which of the following correctly describes the structural organization of the cell membrane?
A bilayer of phospholipid molecules in which protein molecules are embedded and can move
49
What characteristic do simple diffusion and facilitated diffusion share?
Both move a substance from a region of higher concentration to one of lower concentration without cellular energy.
50
Which of the following transport processes does not require expenditure of cellular energy?
Facilitated diffusion
51
A decomposition reaction can be symbolized by
AB → A + B.
52
Cancer can result if
mitosis is too frequent or does not stop.
53
Cells lose water when placed in a __________ solution.
hypertonic
54
Metabolism" refers to
all of the chemical reactions in a cell.
55
Which of the following is an example of catabolism?
The breakdown of glucose in the cytoplasm and mitochondria.
56
Cilia and flagella extend from certain cells, enabling them to move.
true
57
Smooth endoplasmic reticulum has ribosomes and rough endoplasmic reticulum does not.
false
58
A cell that can divide to give rise to any cell type is
totipotent.
59
Cilia and flagella extend from certain cells, enabling them to move.
true
60
An enzyme is
a molecule, usually a protein, that speeds the rate of a biochemical reaction by lowering the activation energy.
61
A cofactor is ______ and examples are _____.
a necessary part of some enzymes; copper, iron, and zinc
62
ATP is important to cellular processes because it
provides energy for cellular work when the terminal, high-energy bond is broken.
63
Mutagens are factors that cause mutation.
true
64
Codons are part of
mRNA
65
The electron transport chain is a series of enzyme complexes that pass electrons, releasing energy that is used to phosphorylate ADP to ATP on the inner mitochondrial membrane.
true
66
A DNA molecule is a double helix in which A pairs with C and T pairs with G
false
67
Histology is the study of the history of anatomy and physiology
false
68
Which of the following is not one of the four basic types of body tissues?
Epithelial tissue
Connective tissue
correct Eye tissue
Muscle tissue
69
Four basic groups of tissues
epithelial, connective, muscle, nervous tissue
70
Which of the following characteristics is used to name tissue types?
Organization of cells
71
A basement membrane anchors
epithelial tissue to connective tissue.
72
The type of intercellular junction that forms tubular channels is
a gap junction.
73
desmosomes
blind cells by forming "spot welds" between cell membranes
74
tight junction
close space between cells by fusing cell membranes
75
Epithelial tissue functions in
secretion, absorption, and protection.
76
The type of epithelium that secretes into ducts that open onto surfaces like skin or into body fluids is
glandular epithelium.
77
Adipose tissue is a form of
connective tissue.
78
Tissues are groups of cells that have a common overall function, yet are distinctive in their characteristic cell types and the molecules that the cells produce.
true
79
Extracellular matrix consists of
ground substance and protein fibers.
80
Tendons and ligaments are composed primarily of
dense regular connective tissue.
81
Involuntary muscle tissues are
smooth muscle tissue and cardiac muscle tissue
82
Muscle cells with more than one nucleus are
skeletal muscle cells only
83
Smooth muscle is found in the wall of the
stomach and intestine
84
Functions of neuroglia include which of the following?
They support and bind nervous tissue and provide nutrients and growth factors to neurons by connecting them to blood vessels
85
The tissue that forms the outermost layer of the skin is a type of connective tissue
false
86
Blood is composed of red blood cells, white blood cells, and platelets suspended in a fluid extracellular matrix called plasma
true
87
The human integumentary system includes
skin, nails, hair follicles, and sweat glands
88
Cutaneous membrane" refers to
skin
89
The dermis is composed largely of
dense irregular connective tissue
90
Skin cells play an important role in producing
vitamin D
91
The functions of skin include
acting as a protective covering.
housing sensory receptors.
regulating body temperature.
correct all of the above.
92
Two thieves steal jewelry, and then drop it as they are escaping. The police recover the jewelry, and an officer explains on the evening news that fingerprints were obtained from the back of a watch. The thieves, whose prints are not on file, believe that they can escape prosecution by using acid to remove the epidermis on their fingerpads, so as not to be a match for the fingerprints on the watch. They are wrong because
the prints arise from friction ridges of the dermis, which are not destroyed.
93
The layer of the epidermis that includes melanocytes and a single row of columnar cells that undergo mitosis is the
stratum basale.
94
The skin appears yellowish if a person eats too much
carotene.
95
Which of the following is not correct concerning the skin?
The subcutaneous layer is between the dermis and the epidermis.
96
Nerve fibers scattered throughout the dermis are associated with
muscles, glands, and sensory receptors
97
A nail consists of
a nail bed and nail plate
98
The hardness of a nail comes from
keratin
99
Inflammation makes skin
red, swollen and painful to touch.
100
Eumelanin and pheomelanin are
brownish-black and reddish-yellow pigments, respectively.
101
Shafts of hair are composed of
dead epidermal cells.
102
In treating a burn patient, the "rule of nines" is used to estimate the
surface area of the burn.
103
As a person ages, the skin typically becomes
potted with patches of pigment
104
Cutaneous carcinomas are usually caused by regular exposure to
ultraviolet light.
105
Which person is at highest risk of developing a cutaneous carcinoma?
a light-complexioned man age 52 who goes to the beach on summer weekends and does not use sunblock because he likes to be tan.
106
Melanin production is greater in the skin of people who live outdoors all the time than in people who do not.
true
107
As epidermal cells move up through the strata away from their blood supply, they die and become keratinized.
true
108
A second degree burn is the same as a full-thickness burn
false
109
Reddened skin reflects
dilated blood vessels with more blood entering the dermis.
110
Which of the following happens first after a scab forms?
fibroblasts from the wound edge form new collagenous fibers.
111
The arrector pili muscle is attached to
a hair follicle
112
An anatomical section that separates the body into right and left portions is a __________ section
sagittal
113
A protein that spans the cell membrane is termed a(n)
integral protein.
114
Cilia and flagella extend from certain cells, enabling them to move
true
115
Microfilaments and microtubules are part of the cytoskeleton.
true
116
Filtration requires hydrostatic pressure.
true
117
During interphase, a cell rests.
false
118
Apoptosis is also known as
programmed cell death.
119
Which of the following does not influence the rate of diffusion?
The amount of energy available for transport molecules
120
A parietal layer of a serous membrane _______, whereas a visceral layer of a serous membrane ________.
lines cavities; covers organs
121
Which of the following transport processes does not require expenditure of cellular energy?
Facilitated diffusion
122
Saturated fats _______ than unsaturated fats.
have more single carbon-carbon bonds
123
Which of the following correctly describes the structural organization of the cell membrane?
A bilayer of phospholipid molecules in which protein molecules are embedded and can move
124
Cells lose water when placed in a __________ solution.
hypertonic
125
The secondary structure of a protein molecule is the result of
hydrogen bonds
126
If the concentration of glucose in the water outside of a cell is higher than the concentration inside,
water will leave the cell by osmosis
127
Which of the following substances increases in abundance during cellular respiration?
ATP
128
Which of the following is not true regarding RNA?
It is transcribed in the nucleus and enters the cytoplasm.
It includes ribose, a 5-carbon sugar.
correct It is double-stranded.
It has cytosine as one of its four nitrogenous bases.
129
Transcription and translation differ in that
transcription produces RNA and translation produces protein.
130
A cell may contain hundreds of different types of enzymes
true
131
An ATP molecule consists of an adenine, a ribose, and three phosphates
true
132
The aerobic reactions of cellular respiration occur in the mitochondria.
true
133
A DNA molecule is a double helix in which A pairs with C and T pairs with G
false
134
A _______ membrane lines tubes and cavities that open to the outside of the body.
mucous
135
Eccrine sweat glands differ from sebaceous glands
in type of secretion.
in their location.
in whether or not they are associated with hair follicles.
correct all of the above.
136
atom
smallest particle of an element that has the properties of that element.
137
elements
naturally occurring matter on earth is composed of 92 elements. Elements are composed of atoms.
138
molecule
particle formed by the chemical union of two or more atoms
139
elements usually occur in combinations called what
compounds
140
atomic number
of an element is equal to the number of protons in each atom.
141
atomic weight
is equal to the number of protons plus the number of neutrons in each atom.
142
ion
particle that is electrically charged because it has gained or lost one or more electrons.
143
What is the relationship between matter and elements?
All matter is composed of fundamental substances.
144
Where are electrons, protons, and neutrons located within an atom?
the nucleus of an atom
145
What is an isotope?
Atoms that have the same atomic number but different atomic weight.
146
Describe 4 types of chemical reactions.
Synthesis: when 2 or more atoms, ions, or molecules bond to form a more complex structure A+B->AB
Decomposition: bonds of a reactant molecule break to form simpler molecules, atoms, or ions AB->A+B
Exchange: parts of 2 different types of molecular trade positions as bonds are broken and new are formed AB + CD-> AD+ BC
Reversible: product or products can change back to reactant or reactants A+B AB
147
Compare the chemical composition of carbohydrates, lipids, proteins, and nucleic acid.
Carbohydrates: C, H, O
Lipids: C, H, O (often P)
Protein: C, H, O, N, ( often S)
Nucleic acids: C, H, O , N , P
148
Compare the characteristics of an acid, a base & a salt.
Acid: substance that releases hydrogen ion
Base: substance that release ions that can combine with hydrogen ions
Salt: substance formed by the reaction between and acid and a base.
149
A hydrophilic molecule dissolved in....
water
150
What are the general difference between an organic molecule and an inorganic molecule?
Organic: compounds have carbon and hydrogen.
Inorganic: all other chemicals, chemicals that does not include both carbon and hydrogen atoms.
151
Most abundant inorganic compound in the body
water
152
two or more substances chemically combined
compounds
153
How many electrons can fit in the 1st, 2nd, and 3rd shells of an atom
First Shell-2
Second Shell-8
Third Shell-8
154
alkalosis
blood pH of 7.5 to 7.8 (makes one feel dizzy and agitated)
155
acidosis
pH between 7.0 to 7.3 (makes one feel disoriented and fatigued)
156
Levels of Structure of Proteins
Primary, Secondary, Tertiary, Quaternary
157
Primary Structure
the amino acid sequence of the polypeptide chain
158
Secondary Structure
the polypeptide chain forms wither an alpha helix (coils) or a beta-pleated sheet (folds) Arise from hydrogen bonding
159
Tertiary Structure
when hydrogen bonding and covalent bonding between atoms in different parts of a polypeptide impart another larger level of folding
160
Quarternary Structure
two or more polypeptide chains may be connected to form a single protein molecule ex hemoglobin
161
facilitated diffusion
passive transport in which a solute binds to a specific carrier on one side othe the membrane and is released on the other side.
162
primary active transport
uses energy derived from hydrolysis of ATP to change the shape of a carrier protein, which pumps a substance across a cellular membrane against tis concentration gradient.
163
filtration
smaller molecules are forced through a porous membranes from regions of higher pressure to regions of lower pressure (molecules leaving blood capillaries)
164
exocytosis
vesicles fuse with membrane and release contents outside the cells (protein secretion, neurotransmitter release)
165
transcytosis
combines receptor-mediated endocytosis and exocytosis to ferry particles through the cell. (HIV crossing a cell layer)
166
receptor-mediated (endocytosis)
membrane engulfs selected molecules combined with receptor proteins.
167
active transport
carrier molecules transport molecules or ions through membranes from regions of lower concentration towards regions of higher concentration. (movements of various ions
168
pinocytosis
membrane engulfs droplets of liquid from surrounding cells.
169
The relationship of osmotic pressure and the number of solute particles in a solution is the
lower the number of solute particles, the greater the osmotic pressure.
greater the number of solute particles, the lower the osmotic pressure.
greater the osmotic pressure, the lower the number of solute particles.
greater the number of solute particles, the greater the osmotic pressure.
greater the number of solute particles, the greater the osmotic pressure.
170
```
An organic compound always contains
carbon and hydrogen.
oxygen and nitrogen.
carbon and oxygen.
nitrogen and hydrogen.
```
carbon and hydrogen.
171
Which of the following groups of compounds is hydrophobic?
lipids
172
The process by which cells specialize is called differentiation.
true
173
Which of the following transport processes does not require expenditure of cellular energy?
Facilitated diffusion
174
In phagocytosis
| a cell membrane engulfs solid particles.
a cell membrane engulfs solid particles.
175
```
If the concentration of glucose in the water outside of a cell is higher than the concentration inside,
water will enter the cell by osmosis.
water will leave the cell by osmosis.
glucose will enter the cell by osmosis.
glucose will leave the cell by osmosis
```
water will leave the cell by osmosis
176
Stages of the cell cycle unfold in the following order:
differentiation, cytoplasmic division, mitosis, interphase
interphase, differentiation, cytoplasmic division, mitosis
interphase, mitosis, cytoplasmic division, differentiation
mitosis, interphase, cytoplasmic division, differentiation
interphase, mitosis, cytoplasmic division, differentiation
177
A cofactor is ______ and examples are _____.
an inorganic molecule that all enzymes require; cholesterol and calcium
an inorganic molecule that some enzymes require; vitamin B12 and B6
a necessary part of some enzymes; copper, iron, and zinc
a molecule that destabilizes substrates; carbonic acid
a necessary part of some enzymes; copper, iron, and zinc
178
ATP is important to cellular processes because it
is formed by muscles contracting or whenever cellular work occurs.
provides energy for cellular work when the terminal, high-energy bond is broken.
releases oxygen when high-energy phosphate bonds are broken.
is a by-product of all catabolic reactions.
provides energy for cellular work when the terminal, high-energy bond is broken.
179
```
A glucose molecule is broken down into two pyruvic acid molecules in
glycolysis.
the citric acid cycle.
gluconeogenesis.
the electron transport system.
```
glycolysis
180
Which choice lists structures in order of increasing size?
nitrogenous base - nucleotide - gene - chromosome - genome
nitrogenous base - nucleotide - gene - genome - chromosome
genome - nucleus - chromosome - nucleotide - gene
cell - organelle - tissue - organ
nitrogenous base - nucleotide - gene - chromosome - genome
181
Which of the following is not true regarding RNA?
It is transcribed in the nucleus and enters the cytoplasm.
It includes ribose, a 5-carbon sugar.
It is double-stranded.
It has cytosine as one of its four nitrogenous bases.
It is double-stranded.
182
The electron transport chain is a series of enzyme complexes that pass electrons, releasing energy that is used to phosphorylate ADP to ATP on the inner mitochondrial membrane.
true
183
cranial cavity
houses the brain
184
spinal cavity
houses the spinal cord
185
thoracic cavity
contains the lungs and heart
186
abdominal cavity
contains the stomach, liver, spleen, gallbladder, kidneys, and the small and large intestines.
187
pelvic cavity
contains the terminal end of the large intestine, the urinary bladder, and the internal reproductive organs.
188
line the walls of the thoracic and abdominopelvic cavities and fold back to cover the organs within these cavities. These membranes secrete a slippery serous fluid that separates the layer lining the wall of the cavity (parietal layer) from the layer covering the organ (visceral layer).
serous membranes
189
Proximal
Closer to the origin of the body part or the point of attachment of a limb to the body trunk
190
distal
Away from or farthest from the trunk or the point of origin of a body part
191
medial
closer to the mid line of the body
192
Proximal
Closer to the origin of the body part or the point of attachment of a limb to the body trunk
193
distal
Away from or farthest from the trunk or the point of origin of a body part
194
lateral
Away from the midline of the body
195
superior
Higher on the body, nearer to the head
196
inferior
Away from the head end or toward the lower part of a structure or the body; below.
197
ventral
At the belly side
198
Name the bulk elements in the human body.
carbon, hydrogen, oxygen, nitrogen, sulfur, and phosphorus
199
How do you indicate an ion in a molecular formula?
negative ions have (-), positive ions have (+)
200
neutral
A pH of 7., A liquid that is neither an acid nor base
201
how does the number of solute particles in a solution affect osmotic pressure?
The greater the concentration of impermeant solute particles (protein in this case) in a solution, the lower the water concentration of that solution and the greater the osmotic pressure
202
interphase
G1-cell growth, S-genetic material replicates, G2-cell growth
203
mitosis
cell division; prophase, metaphase, anaphase, telophase
204
prophase
the chromatin fibers condense, making the individual chromosomes visible
205
metaphase
spindle fibers attach to the centromeres so that a fiber accompanying one chromatid attaches to one centromere and a fiber accompanying the other chromatid attaches to its centromere. The chromosomes move along the spindle fibers, and microtubules help align them about midway between the centrioles
206
anaphase
The separated chromosomes move in opposite directions, again as the result of microtubule activity. The spindle fibers shorten and pull their attached chromosomes toward the centrioles at opposite sides of the cell
207
telophase
the final stage of mitosis, the chromosomes complete their migration toward the centrioles. As the identical sets of chromosomes approach their respective centrioles, they begin to elongate and unwind from rodlike structures to threadlike structures. A nuclear envelope forms around each chromosome set, and nucleoli become visible within the newly formed nuclei. Finally, the microtubules disassemble into free tubulin molecule
208
cytokinesis
completes the cell division process by dividing the cytoplasm into two daughter cells, each with a nucleus
209
cell differentiation
the process by which a cell becomes specialized for a specific structure or function
210
tumor
A mass of abnormal cells that develops when cancerous cells divide and grow uncontrollably.
211
benign tumor
A mass of abnormal cells that remains at the site of origin.
212
malignant tumor
An abnormal tissue mass that can spread into neighboring tissue and to other parts of the body; a cancerous tumor.
213
stem cells
unspecialized cells that retain the ability to become a wide variety of specialized cells
214
progenitor cell
Cells that are between differentiated cells and stem cells. Have a limited capacity of which cells they may become.
215
anabolism
Constructive metabolism; the process of building up larger molecules from smaller ones. dehydration synthesis
216
catabolism
Breakdown of biochemical substances into simpler substances; hydrolysis
217
dehydration synthesis
A chemical reaction in which two molecules covalently bond to each other with the removal of a water molecule; monosaccharides can be joined this way to produce disaccharides or polysaccharides.
218
hydrolysis
A chemical reaction that breaks bonds between two molecules by the addition of water; functions in disassembly of polymers to monomers
219
what type of organic molecules are enzymes?
proteins
220
what is the function of an enzyme in metabolism?
to increase the rate of chemical reactions
221
what is the function of an enzyme in the body?
to promote life
222
coenzyme
a cofactor that is an ion of an element, such as copper, iron, or zinc, or a small organic molecule,
223
How are vitamins important to enzymes?
Vitamins provide coenzymes that can function repeatedly
224
ATP
(adenosine triphosphate) main energy source that cells use for most of their work, 3 phosphate groups, (1 ribose, 1 adenine---hydrolyzed to make ADP and release energy
225
cellular respiration
A complex set of chemical reactions involving an energy transformation where potential chemical energy in the bonds of "food" molecules is released and partially captured in the bonds of adenosine triphosphate (ATP) molecules.
226
glycolysis
Catabolism of glucose or other monosaccharides to pyruvate and 2 molecules of ATP in the absence of oxygen or 34 molecules of ATP in the presence of oxygen., - occurs in cytoplasm
227
citric acid cycle
A chemical cycle involving eight steps that completes the metabolic breakdown of glucose molecules to carbon dioxide; occurs within the mitochondrion; the second major stage in cellular respiration.
228
electron transport chain
A series of molecules, found in the inner membranes of mitochondria and chloroplasts, through which electrons pass in a process that causes protons to build up on one side of the membrane.
229
gene
A DNA sequence that contains the information for making a particular protein
230
chromosome
A threadlike, gene-carrying structure found in the nucleus. Each chromosome consists of one very long DNA molecule and associated proteins.
231
genome
All of an organism's genetic material.
232
complementary base pairing of nucleotides
Hydrogen bonding between particular pyrimidines and purines. Adenine & Thymine. Cytosine & Guanine.
233
DNA
A double-stranded, helical nucleic acid molecule capable of replicating and determining the inherited structure of a cell's proteins.
234
RNA
A type of nucleic acid consisting of nucleotide monomers with a ribose sugar and the nitrogenous bases adenine (A), cytosine (C), guanine (G), and uracil (U); usually single-stranded; functions in protein synthesis and as the genome of some viruses.
235
protein synthesis
Forming proteins based on information in DNA and carried out by RNA
236
what are the major stages of protein synthesis?
transcription and translation
237
transcription
Enzymes (RNA Polymerase use nucleotide sequence of a gene to synthesize a complementary strand of RNA (mRNA
238
translation
A step in protein biosynthesis wherein the genetic code carried by mRNA is decoded to produce the specific sequence of amino acids in a polypeptide chain. The process follows transcription in which the DNA sequence is copied (or transcribed) into an mRNA.
239
codon
A three-nucleotide sequence of DNA or mRNA that specifies a particular amino acid or termination signal; the basic unit of the genetic code.
240
anti-codon
A sequence of three bases of a tRNA molecule that pairs with the complementary three-nucleotide codon of an mRNA molecule during protein synthesis.
241
mutation
the mechanism of change in a DNA sequence.
242
mutagen
A chemical or physical agent that interacts with DNA and causes a mutation.
243
tight junction
Cell-to-cell communication. Prevents leakage across a layer of epithelial cells in animals. Adjacent cell membranes are fused forming a seal. (Ex.- Epithelium in urinary bladder)
244
desmosome
Anchoring junctions that prevents cells subjected to mechanical stress from being pulled apart; button like thickenings of adjacent plasma membranes connected by fine protein filaments
245
gap junction
Communicating Junctions; channels that allow small molecules to flow through protein-lined pores between cells
246
epithelial tissue
function= protection, excretion, absorption, secretion. Location= cover body surface, cover and line internal organs, compose glands. characteristics= lack blood vessels, cells readily divide, cells are tightly packed
247
connective tissue
function= bind, support, protect, fill spaces, store fat, and produce blood cells. location= widely distributed throughout the body. characteristics= good blood supply, cells are farther apart, have extracellular matrix in between
248
muscle tissue
function= movement. location= attached to bones, in the walls of hollow internal organs, heart. characteristics= contract in response to stimuli
249
nervous tissue
function= conduct impulses for coordination, regulation, integration, and sensory reception. location= brain, spinal cord, nerves. characteristics= communicate with each other and other body parts
250
basement membrane of epithelial tissues
anchors epithelium to underlying connective tissue.
251
simple
a single layer of cells
252
stratified
A thick epithelium, because of the several layers of cells
253
pseudostratified columnar
Single layer of cells of differing heights, some not reaching the free surface; nuclei seen at different levels; may contain goblet cells and bear cilia.
254
Transitional epithelium
specialized to change in response to increased tension
255
squamous
these cells fit tightly together, somewhat like floor tiles, and their nuclei are usually broad and thin
256
simple squamous
```
function= filtration, diffusion, osmosis, covers surface
location= air sacs of lungs, walls of capillaries, lining of blood vessels
```
257
simple cuboidal
Function: secretion and absorption; location-, Kidney tubules; ducts and secretory portions of small glands; ovary surface
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simple columnar
Function: absorption & secretion, protection. location- linings of the uterus, stomach, intestines
259
pseudostratified columnar
function= protection, secretion, movement of mucus and substances. Location- linings of the respiratory passage
260
stratified squamous
function= protection; , Location: Epidermis, Lining the openings of open tracts (mouth, esophagus, vagina and anal canal)
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stratified cuboidal
Location: Lining in the ducts of mammary glands, sweat glands, salivary glands, and pancreas. Function: Protection, secretion
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stratified columnar
Location: lines the male urethra, and ducts of excretory glands; function: protection, secretion
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transitional epithelium
function: distensibilty, protection; Found in the urinary tract organs
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glandular epithelium
function: secretion; location: salivary glands, sweat glands, endocrine glands
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merocrine glands
Exocrine glands that secrete without losing cellular material.
266
apocrine glands
Loses a part of the cell body, which forms secretion
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holocrine glands
Exocrine glands whose secretions are made up of disintegrated cells.
268
extracellular matrix of connective tissue
composed of protein fibers and a ground substance consisting of nonfibrous protein and other molecules, and fluid.
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fibroblast
Cells in the connective tissue that produce extracellular fibers ( collagenous, elastic and reticular fibers)
270
macrophage
cells in the connective tissue that originate as white blood cells that fight off infection
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mast cells
Cells that release chemicals (such as histamine) that promote inflammation.
272
collagenous fibers
These are thick threads of protein, grouped in long, parallel bundles that are flexible but only slightly elastic; these fibers have great tensile strength - that is, they resists considerable pulling force; these fibers form ligaments (which connects bones to bones) and tendons (which connect muscles to bones) (p. 100).
273
elastic fibers
Composed of yellow elastin, very stretchy, not as strong as collagen; Vocal cords and air passages
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reticular fibers
Fine branched collagen fibers; a network or framework for organs
275
synovial membrane
Line the cavities of freely moveable joints (i.e. shoulder, elbow, knee etc). 2. Secrete a fluid called synovial fluid which lubricates and nourishes the cartilage covering the bones.
276
functions of the skin
Skin is a protective covering, retards water loss, helps regulate body temperature, houses sensory receptors, contains cells that play a role in immunity, aids in the formation of vitamin D from its precursor, and excretes wastes.
277
what is an injection administered into the skin?
intradermal injection
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3 layers of the skin
epidermis, dermis, hypodermis (subcutaneous layer)
279
epidermis
Composed of stratified squamous epithelium. Thickest on palms and soles of feet. Rests on basement membrane. Keratinized.
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dermis
Contains blood vessels, hair fallicles, sweat glands, and oil glands, nerve cells.; papillary layer is composed of areolar connective tissue. The lower or reticular layer is dense irregular connective tissue that includes tough collagenous fibers and elastic fibers in a gel-like ground substance.
281
hypodermis
Aso called a subcutaneous layer, this is a layer of *fat located under the dermis of the skin. helps to insulate the body and protects underlying muscles and other structures.
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stratum corneum
first layer of the epidermis. Many thick, dead flattened cell layers, dead cells filled with keratin,protect against abrasions and penetration.
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stratum lucidem
2nd layer of epidermis. the very thin layer of the epidermis that appears clear and consists of dead cells; it is only present in thick skin in certain areas of the body; disperses keratohyalin around keratin fibers
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stratum granulosum
3rd layer of the epidermis. 3-5 layers of flattened polygonal cells thick, cytoplasm filled with course basophilic granules (aka keratohylin granules
285
stratum spinosum
4th layer of the epidermis. 8-10 layers of cells - Limited cell division. As cells push to surface, they flatten;Desmosomes break apart and new ones form. Lamellar bodies (lipid-filled membrane-bound organelles) and additional keratin fibers form
286
stratum basale
Bottom layer of the epidermis. Consists mainly of a single layer of cuboidal to low columnar stem cells and keratinocytes resting on the basement membrane.
287
How are finger prints created on the skin?
Dermal papillae
288
dark hair color
eumelanin
289
blonde and red
pheomelanin
290
hypothermia
Abnormal lowering of the body temp below 35 C or 95 F usually caused by prolonged exposure to cold
291
hyperthermia
An elevated body temperature related to the body's inability to promote heat loss or reduce heat production. greater than 98.6
292
What are the effects of inflammation of the skin?
Blood vessels in affected tissues dilate and become more permeable, allowing fluids to leak into the damaged tissues
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healing a wound
a, blood escapes from dermal blood vessels, and (d) a blood clot soon forms. (e) The blood clot and dried tissue fluid form a scab that protects the damaged region. (f) Later, blood vessels send out branches, and fibroblasts migrate into the area. The fibroblasts produce new connective tissue fibers, and (g) when the skin is mostly repaired, the scab sloughs off. Scar tissue continues to form, elevating the epidermal surface.
294
cutaneous carcinomas (basal cell, squamous cell) cutaneous melanomas (melanocarcinomas, malignant melanomas)
What are the types of skin cancer?
295
How can cancer be prevented?
To reduce risk of developing skin cancer, avoid exposure to high-intensity sunlight, use sunscreens and sunblocks, and examine the skin regularly.
296
what is the primary cause of skin cancer?
Skin cancer begins when the sun (or tanning bed) exposure overwhelms the protection provided by p53
