Chapter 3 Flashcards
1
Q
Nucleus
A
The control center. Contains the genetic material of the cell.
2
Q
Nuclear Envelope
A
A double membrane barrier that bounds the nucleus; selectively permeable
3
Q
Nuclear Pores
A
When the two layers of the nuclear envelope fuse, these penetrate through the fused region.
4
Q
Nucleoli
A
Small, dark-staining, essentially round bodies. They are sites where ribosomes are assembles.
5
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Chromatin
A
A loose network of bumpy threads that are scattered throughout the nucleus.
6
Q
Chromosomes
A
When a cell is dividing to form two daughter cells, the chromatin threads coil and condense to form dense, rodlike bodies.
7
Q
Plasma Membrane (a.k.a. Cell Membrane)
A
A fragile, transparent barrier that contains the cell contents and separates them from the surrounding environment.
8
Q
Microvilli
A
Tiny fingerlike projections that greatly increase the cell’s surface area for absorption so that the process occurs more quickly.
9
Q
Membrane Junction
A
Vary structurally depending on their roles. The 3 types are tight, desmosomes, and gap.
10
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Tight Junctions
A
Impermeable junctions that bind cells together into leakproof sheets that prevent substances from passing through the extracellular space between cells.
11
Q
Desmosomes
A
Anchoring junctions that prevent cells subjected to mechanical stress from being pulled apart.
12
Q
Gap Junctions
A
Functions mainly to allow communication. Neighboring cells are connected by connexons. Most commonly seen in the heart and between embryonic cells.
13
Q
Connexons
A
Hollow cylinders composed of proteins that span the entire width of the abutting membranes. They connect the neighboring cells in gap junctions.
14
Q
Cytoplasm
A
The cellular material outside the nucleus and inside the plasma membrane. It is the site of most cellular activities.
15
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Cytosol
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Semitransparent fluid that suspends the other elements.
16
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Organelles
A
The metabolic machinery of the cell. Each type is specialized to carry out a specific function as a whole.
17
Q
Inclusions
A
Chemical substances that may or may not be present, depending on the specific cell type. Most are stored nutrients or cell products.
18
Q
Mitochondria
A
Usually depicted as tiny threadlike or sausage-shaped organelles, but in living cells they squirm, lengthen, and change shape continuously. “Powerhouse” of the cell.
19
Q
Ribosomes
A
Tiny, bilobed, dark bodies made of proteins and one variety of RNA called ribosomal RNA. The actual sites of protein synthesis in the cell.
20
Q
Endoplasmic Reticulum
A
A system of fluid-filled cisterns that coil and twist through the cytoplasm. It provides a a network of channels that carry substances from one part of the cell to another.
21
Q
Rough ER
A
Studded with ribosomes. Can be called the cell’s membrane factory because all of the building materials of cellular membranes are formed either in it or on it.
22
Q
Transport Vesicles
A
The proteins made on the ribosomes of the rough ER migrate into tubules, where they fold into their functional three-dimensional shapes and then are dispatched to other areas of the cell in these.
23
Q
Smooth ER
A
It functions in lipid metabolism, and detoxification of drugs and pesticides.
24
Q
Golgi Apparatus
A
A stack of flattened membranous sacs, associated with swarms of tiny vesicles. “Traffic Director” of the cell. Its major function is to modify and package proteins in specific ways.
25
Secretory Vesicles
As proteins "tagged" for export accumulate in the Golgi Apparatus, the sacs swell, and the swollen ends, filled with proteins, pinch off and form these. They travel to the plasma membrane.
26
Lysosomes
Membranous "bags" containing powerful digestive enzymes. They appear in different sizes. Function as the cell's demolition site.
27
Peroxisomes
Membranous sacs containing powerful oxidase enzymes that use molecular oxygen to detoxify a number of harmful or poisonous substances. Most important function is to "disarm" dangerous free radicals.
28
Free Radicals
Highly reactive chemicals with unpaired electrons that can scramble the structure of proteins and nucleic acids.
29
Cytoskeleton
An elaborate network of protein structures that extends throughout the cytoplasm. Acts as a cell's "bones and muscles" by furnishing an internal framework that determines cell's shape, supports other organelles, and provides the machinery needed for intracellular transport and various types of cellular movements. Made up of microtubules, intermediate filaments, and microfilaments.
30
intermediate Filaments
Strong, stable rope-like structures that help form desmosomes and provide internal guy wires to resist pulling forces on the cell.
31
Microfilaments
Most involved in cell motility and in producing changes in cell shape
32
Microtubules
Tubelike structures that determine the overall shape of a cell and the distribution of organelles. They are very important during cell division.
33
Centrioles
Rod-shaped bodies that lie at right angles to each other; internally they are made up of fine microtubules. They are best known for their role in generating microtubules and during cell division.
34
Cilia
Whiplike cellular extensions that move substances along the cell surface.
35
Flagella
Projections formed by the centrioles are substantially longer.
36
Ribosomes
______ are found on the rough ER and in the cytoplasm
37
cytoplasm
Cytosol, organelles, and inclusions are all components of the ____________
38
cytoskelton
internal framework for cell & is made of microtubules, intermediate filaments, & microfilaments
39
Flagella
_______ uses a long tail for swimming
40
Gap Junctions
allows cell communication
41
Centrioles
form mitotic spindle
42
Mitochondria
captures energy to produce ATP
43
Ribosome
site of protein synthesis
44
Lysosome
digest worn out/nonusable cell structures
45
Golgi Apparatus
packages substances for release from cell
46
Endocytosis
Process of _____ requires energy from the cell
47
Hypertonic
When a cell is placed in a ____ solution, it will shrink or crenate
48
Passive transport
Diffusion and filtration are both a type of ____________
49
Prophase, Metaphase, Anaphase, Telophase
Order of the Phases of Mitosis
50
Codon
mRNA sagment that carries information coding a particular amino acid
51
Ribosomes
needed for protein synthesis
52
DNA
made during replication
53
Adipose
Fat is a type of ____ tissue
54
Smooth muscle
Found in walls of hollow organs & walls of blood vessels
55
Prophase
Centrioles separate & move toward opposite sides of cell
56
Telophase
Cytokinesis via cleavage produces 2 daughter cells
57
Solution
homogeneous mixture of two or more components.
58
Solvent
The substance present in the largest amount in the solution. Dissolving medium.
59
Solutes
Components or substances present in smaller amounts.
60
Intracellular Fluid
Collectively the nucleoplasm and cytosol. A solution containing small amounts of gases (carbon dioxide and oxygen), nutrients, and salts, dissolved in water.
61
Interstitial Fluid
The fluid that continuously bathes the exterior of our cells. Can be thought of as rich, nutritious, and rather unusual "soup."
62
Selective Permeability
Means that a barrier allows some substances to pass through it while excluding others.
63
Passive Transport
Substances are transported across the membrane without any energy input from the cell.
64
Active Transport
The cell provides the metabolic energy (ATP) that drives the transport process.
65
Diffusion
The process by which molecules (and ions) move away from a region where they are more concentrated to a region where they are less concentrated.
66
Concentration Gradient
The amount of substance determines their position on this.
67
Simple Diffusion
The unassisted diffusion of solutes through the plasma membrane.
68
Osmosis
Diffusion of water through a selectively permeable membrane such as the plasma membrane.
69
Facilitated Diffusion
Provides passage for certain needed substances that are both lipid-insoluble and too large to pass through the membrane pores.
70
Filtration
The process by which water and solutes are forced through a membrane by fluid or hydrostatic pressure.
71
Pressure Gradient
In filtration, this gradient actually pushes solute-containing fluid form the higher-pressure area to the lower-pressure area.
72
Active Transport
requires protein carriers that combine reversibly with the substances to be transported across the membrane ans uses ATP to energize its protein carriers
73
vesicular transport
involves ATP and moves substances into or out of cells without their actually crossing the plasma membrane
74
Vesicular
Exocytosis and endocytosis are 2 types of _______ transport.
75
Exocytosis
"out of the cell;" moves substances out of the cells; means by which vells actively secrete horomones, mucus, and other cell products or eject certain cellular wastes
76
Endocytosis
"into the cell;" includes those ATP requiring processes that take up (engulf) extracellular substances by enclosing them in a samll membranous vesicle
77
Phagocytosis
"cell eating;" specific endocytosis process when the engulfed substances are relatively large particles such as bacteria or dead body cells, which are separatd from the external environment by flowing cytoplasmic extensions called pseudopods
78
Pinocytosis
"cell drinking;" specific endocytosis process where the cell "gulps" droplets of extracellular fluid
79
Receptor-mediated endocytosis
main cellular mechanism for taking up specific target molecules; the plasma membrane receptor proteins bind only with certain substances
80
Interphase and Cell Division
the two major periods of the cell cycle
81
Interphase
the cell grows and carries on its usual metabolic activities
82
cell division
(major) period when the cell produces itself
83
Interphase
longest phase of the cell cycle
84
Metabolic phase
A more accurate name for interpahse would be _____ ______.
85
Interphase
the cell is very active and is resting only from divsion during this phase of the cell cycle
86
Template
Each nucleotide strand serves as a ______, or a set of instructions, for building a new nucleotide strand
87
Mitosis
division of the nucleus
88
Cytokinesis
division of the cytoplasm and begins when mitosis is nearly complete
89
Prophase
phase of mitosis when the chromatin threads coil and shorten so that visible bar like bodies (chromosomes) appear
90
Chromosome
visible bar like body; "colored body"
91
Template
Each nucleotide strand serves as a ______, or a set of instructions, for building a new nucleotide strand
92
Chromatid
the two strands of a chromosome are called a ______
93
Centromere
each chromatin is held together by a small buttonlike body called a _________
94
Mitotic Spindle
composed of microtubules; when the centrioles separate from eac other and begin to move to opposite sides of the cell, the assembly of a ___________ is directed
95
metaphase
short phase of mitosis when the chromoses cluster and become aligned at the middle; a straight line of chromosomes is seen
96
anaphase
phase of mitosiswhen the centromeres that have held the chromatids together split; the chromatids begin to move sowly apart, drawn toward opposite ends of the cell; this phase is over when chromosome movement ends
97
telophase
phase of mitosis when the chromosomes at opposite ends of the cell uncoil to become threadlike chromatin again; the spindle breaks downs and disappears, a nuclear envelope forms around each chromatin mass, and nucleoli appear in each of the daughter nuclei
98
gene
DNA segment that carries the information for building one protein or polypeptide chain
99
Fibrous (structural) proteins
protein that is the major building material for cells
100
Globular (functional) proteins
protein that includes enzymes and some horomones
101
enzymes
biological catalyst that regulate chemical reactions in cells
102
Ribonucleic Acid (RNA)
A second type of nucleic acid that carries out the messenger and decoder functions .
103
Transfer RNA (tRNA)
Small, clover-leaf shaped molecules. Its job is to ferry amino acids to the ribosome, where they are bound together by the enzymes. 45 common types, each capable of carrying one of the 20 or so common types of amino acids to the protein synthesis sites. They also have to recognize the mRNA codons "calling for" the amino acid they are toting.
104
Ribosomal RNA (rRNA)
Helps form the ribosomes, where proteins are built.
105
Messenger RNA (mRNA)
Long, single nucleotide strands that resemble half of a DNA molecule and carry the "message" containing instructions for protein synthesis from the DNA gene in the nucleus to the ribosomes in the cytoplasm.
106
Transcription
Involves the transfer of information from DNA's base sequence into the complementary base sequence of mRNA. Only involves mRNA and DNA.
107
Triplet
Each three-base sequence specifying a particular amino acid on the DNA gene.
108
Codons
The corresponding three-base sequences to the DNA strands on mRNA.
109
Translation
The language of acids (base sequence) is "translated" into the language of proteins (amino acid sequence). Occurs in the cytoplasm and involves three major varieties of RNA.
110
Anticodon
A special three-base sequence on the tRNA.
111
Tissues
Groups of cells that are similar in structure and function.
112
Epithelial Tissue or Epithelium
The lining, covering, and glandular tissue of the body. Functions include protection, absorption, filtration, and secretion.
113
Glandular Epithelium
Forms various glands in the body.
114
Covering and Lining Epithelium
Covers all free body surfaces and contains versatile cells.
115
Apical Surface
A free (unattached) surface or edge.
116
Basement Membrane
The lower surface of a cell. A structureless material secreted by both the epithelial cells and the connective tissue cells that abut the epithelium.
117
Avascular
Tissues that have no blood supply of their own.
118
Simple Epithelium
One layer of cells. Most concerned with absorption, secretion, and filtration. Usually very thin.
119
Stratified Epithelium
More than one cell layer. Function primarily to protect.
120
Squamous cells
Flattened like fish cells.
121
Cuboidal Cells
Cube-shaped like dice.
122
Columnar Cells
Shaped like columns.
123
Simple Squamous Epithelium
A single layer of thin squamous cells resting on a basement membrane. The cells fit closely together. Usually forms membranes where filtration or exchange of substances by rapid diffusion occurs. Also forms serous membranes (serosae). Found in the air sacs of lungs and it forms the walls of capillaries.
124
Serous Membranes (Serosae)
Slick membranes that line the ventral body cavity and cover the organs in that cavity.
125
Simple Cuboidal Epithelium
One layer of cuboidal cells resting on a basement membrane. Common in glands and their ducts. It also forms the walls of the kidney tubules and cover the surface of the ovaries.
126
Simple Columnar Epithelium
Made up of a single layer of tall cells that fit closely together. Goblet cells are often seen here. Lines the entire length of the digestive tract from the stomach to the anus.
127
Goblet Cells
Produces a lubricating mucus.
128
Mucosae or Mucous Membranes
Epithelial membranes that line body cavities open to the body exterior.
129
Pseudostratified Columnar Epithelium
All of the cells of this rest on a basement membrane. Some of its cells are shorter than others, and their nuclei appear at different heights above the basement membrane. Mainly functions in absorption and secretion.
130
Stratified Squamous Epithelium
The most common stratified epithelium in the body. Usually consists of several layers of cells. Found in sites that receive a good deal of abuse or friction, such as the esophagus, the mouth, and the outer portion of the skin.
131
Stratified Cuboidal Epithelium
Typically has two layers with (at least) the surface cells being cuboidal in shape. Fairly rare in the body, found mainly in the ducts of large glands.
132
Stratified Columnar Epithelium
The surface cells are columnar cells, but its basal cells vary in size and shape. Fairly rare in the body, found mainly in the ducts of large glands.
133
Transitional Epithelium
A highly modified, stratified squamous epithelium that forms the lining of only a few organs-the urinary bladder, the ureters, and part of the urethra. Cells of the basal layers are cuboidal or columnar; those at the free surface vary in appearance.
134
Gland
Consists of one or more cells that make and secrete a particular product.
135
Secretion
The product from a gland. It typically contains protein molecules in an aqueous fluid.
136
Endocrine Glands
Lose their connection to the surface (duct); thus they are often called ductless glands. Their secretions (all hormones) diffuse directly into the blood vessels that weave through the glands. Examples include thyroid, adrenals, and pituitary.
137
Exocrine Glands
Retain their ducts, and their secretions empty through the ducts to the epithelial surface. Include sweat and oil glands, liver, and pancreas, are both internal and external.
138
Connective Tissue
Connects body parts. It is found everywhere in the body. It is the most abundant and widely distributed of the tissue types. It performs many functions but they are primarily involved in protecting, supporting, and binding together other body tissues. So different from other tissues because of its extracellular matrix.
139
Vascularized
Having a good blood supply.
140
Extracellular Matrix
It is produced by the connective tissue cells and then secreted to the exterior. it has two main elements, a structureless ground substance and fibers. Helps connective tissues form a soft packing tissue around other organs, to bear weight, and to withstand stretching and other abuses, such as abrasion, that no other tissue could endure.
141
Ground Substance
An element of the matrix that is composed largely of water plus some adhesion proteins and large, charged polysaccharide molecules.
142
Bone Connective Tissue (Osseous Tissue)
Composed of bone cells sitting in cavities called lacunae and surrounded by layers of a very hard matrix that contains calcium salts in addition to large numbers of collagen fibers. Has a rocklike hardness that gives it an exceptional ability to protect and support other body organs.
143
Cartilage Connective TIssue
Less hard and more flexible than bone. It is found in only a few places in the body. Most widespread in hyaline cartilage. Also consists of fibrocartilage and elastic cartilage.
144
Hyaline Cartilage
Has abundant collagen fibers hidden by a rubbery matrix with a glassy, blue-white appearance. It forms the supporting structures of the larynx, attaches the ribs to the breastbone, and covers the ends of many bones, where they form joints.
145
Fibrocartilage
A highly compressible cartilage that forms the cushion-like disks between the vertebrae of the spinal column.
146
Elastic Cartilage
Found where a structure with elasticity is desired. For example, it supports the external ear.
147
Dense Connective Tissue (Dense Fibrous)
It has collagen fibers as its main matrix element. Crowded between the collagen fibers are rows of fibroblasts. It forms strong, ropelike structures such as tendons and ligaments. It also makes up the lower layers of the skin (dermis), where it is arranged in sheets.
148
Fibroblasts
Fiber forming cells that manufacture the building blocks of the fibers.
149
Tendons
Attach skeletal muscles to bones.
150
Ligaments
Connect bones to joints. They are more stretchy and contain more elastic fibers than tendons.
151
Loose Connective Tissues
Softer and have more cells and fewer fibers than any other connective tissue type except blood.
152
Areolar Tissue
The most widely distributed connective tissue variety in the body. It is a soft, pliable, "cobwebby" tissue that cushions and protects the body organs it wraps. It functions as a universal packing tissue and connective tissue "glue" because it helps to hold the internal organs together and in their proper positions. Provides a reservoir of water and salts for the surrounding tissues.
153
Edema
A condition that occurs when a body region is inflamed and the areolar tissue in the area soaks up the excess fluid like a sponge, and the area swells and becomes puffy.
154
Adipose Tissue
Commonly called fat. It is an areolar tissue in which fat cells predominate. It forms the subcutaneous tissue beneath the skin, where it insulates the body and protects it from bumps and extremes of both heat and cold. It also protects some organs individually.
155
Reticular Connective Tissue
Consists of a delicate network of interwoven reticular fibers associated with reticular cells. It is limited to certain sites. It forms the stroma.
156
Stroma
Internal framework that can support many free blood cells in lymphoid organs such as lymph nodes, the spleen, and bone marrow.
157
Blood (Vascular Tissue)
Considered a connective tissue because it consists of blood cells surrounded by nonliving, fluid matrix called blood plasma. The transport vehicle for cardiovascular system, carrying nutrients, wastes, respiratory gases, and many other substances throughout the body.
158
Muscle Tissues
Highly specialized to contract or shorten, to produce movement.
159
Skeletal Muscle Tissue
Packaged by connective tissue sheets into organs called skeletal muscles, which are attached to the skeleton. They can be controlled voluntarily in order to form the flesh of the body, the so-called muscular system. The cells are long, cylindrical, multinucleate, and have obvious striations. They are elongated to provide a long axis for contraction and are often called muscle fibers.
160
Cardiac Muscle Tissue
Found only in the heart. As it contracts, the heart acts as a pump and propels blood through the blood vessels. Have striations, but are uninucleate, relatively short, branching cells that fit tightly together at junctions called intercalated disks. Involuntary control.
161
Intercalated Disks
Contain gap junctions that allow ions to pass freely from cell to cell, resulting in rapid conduction of the exciting electrical impulse across the heart.
162
Smooth (Visceral) Muscle Tissue
No striations are visible. The individual cells have a single nucleus and are spindle-shaped. Found in the walls of hollow organs such as the stomach, uterus, and blood vessels. As the muscle in the walls contracts, the cavity of an organ alternately becomes smaller or enlarges so that substances are propelled through the organ along a specific pathway. Contracts much more slowly than the other two types. Typically involves peristalsis.
163
Peristalsis
A wavelike motion that keeps food moving through the small intestine.
164
Nervous TIssue or Neurons
Receive and conduct electrochemical impulses from one part of the body to another. Two major functions are irritability and conductivity. Structure is unique because the cytoplasm is drawn out into long processes which allows a single one to conduct an impulse over long distances in the body. Along with supporting cells, they make up the structure of the nervous system.
165
Supporting Cells
Insulate, support, and protect the delicate neurons.
166
Inflammation
A generalized body response that attempts to prevent further injury.
167
Regeneration
A form of tissue repair. It is the replacement of destroyed tissue by the same kind of cells.
168
Fibrosis
A form of tissue repair. It involves repair by dense connective tissue, that is, by the formation of scar tissue.
169
Series of Events of Tissue Injury
1. The capillaries become very permeable.
2. Granulation TIssue Forms.
3. The surface epithelium regenerates.
170
Granulation Tissue
A delicate pink tissue composed largely of new capillaries that grow into the damaged area from undamaged blood vessels nearby. Contains phagocytes that eventually dispose of the blood clot and fibroblasts that synthesize scar tissue to bridge the gap.
171
Neoplasm
An abnormal mass of proliferating cells. Can be either benign or malignant (cancerous).
172
Hyperplasia
When certain body tissues enlarge because there is some local irritant or condition that stimulates the cells.
173
Atrophy
A decrease in size that can occur when an organ or body area loses its normal stimulation.
