Organelles & Epithelial Tissue Part 1 (Quiz 2) Flashcards
1
Q
What is the function of the nucleus?
A
protecting and controlling access to DNA
2
Q
What is the function of the ER?
A
routing, modifying new polypeptide chains, synthesizing lipids
3
Q
What is the function of the Golgi body?
A
modifying new polypeptide chains, receiving, sorting, shipping proteins and lipids (think post office)
4
Q
What is the function of the mitochondria?
A
making ATP by sugar breakdown
5
Q
What is the function of lysosomes?
A
intracellular digestion
6
Q
What is the function of peroxisomes?
A
inactivating toxins
7
Q
What is the function of ribosomes?
A
assembling polypeptide chains
8
Q
What is the function of centrioles?
A
anchor for cytoskeleton
9
Q
Name some membranous organelles
A
-nucleus
-ER
-Golgi body
-vesicles
-mitochondria
-lysosome
-peroxisome
10
Q
What are the 3 nonmembranous organelles we talked about in class?
A
ribosomes, centrosome/centrioles, and cytoskeleton
11
Q
What are the 6 types of membrane proteins?
A
1) ion channel (integral proteins)
2) carrier/transporters (integral proteins)
3) receptor (integral proteins)
4) enzyme (integral and peripheral proteins)
5) linker (integral and peripheral proteins)
6) cell identity marker (glycoprotein)
12
Q
Are ion channels integral proteins, peripheral proteins, or both?
A
integral proteins
13
Q
Are carrier proteins/transporters integral proteins, peripheral proteins, or both?
A
integral proteins
14
Q
Are receptors integral proteins, peripheral proteins, or both?
A
integral proteins
15
Q
Are enzymes integral proteins, peripheral proteins, or both?
A
both
16
Q
Are linker proteins integral proteins, peripheral proteins, or both?
A
both
17
Q
Are cell identity markers integral proteins, peripheral proteins, or both?
A
none of the above ;)
its a glycoprotein!
18
Q
What do linker proteins do?
A
anchor filaments inside and outside the plasma membrane, providing structural stability and shape for the cell
may also participate in movement of the cell or link 2 cells together
19
Q
T/F: theres an enzyme for every chemical reaction
A
true!
20
Q
Are ion channels and carriers/transporters passive or active transport?
A
passive transport (facilitated diffusion)
21
Q
Where are linker proteins usually found?
A
epithelial tissue
22
Q
Where are cell identity markers (glycoproteins) usually found?
A
RBCs
23
Q
Is the cytoskeleton membranous or non-membranous?
A
non-membranous
24
Q
A cells internal framework is called the….
A
cytoskeleton
(helps w/ structure, support, protection, and leverage)
25
Is the cytoskeleton permanently rigid?
no!
26
The cytoskeleton is a network in the cytoplasm composed of 3 protein filaments. What are they?
-microfilaments
-intermediate filaments
-microtubules
27
Which protein filament of the cytoskeleton is the largest? smallest?
largest= microtubules
smallest= microfilaments
28
What protein are microtubules made with?
tubulin
29
What is the function of microtubules and where are they found?
-spatially organize interior of the cell
-create movement
-form spindles during cell division
-found within flagella and cilia
30
What is the function of microfilaments and where is it found?
-reinforce parts of the cell
-sits under the plasma membrane (if folded, then there will also be microvilli)
31
What is the function of intermediate filaments?
-add strength
-provide spaces/compartments to organize the organelles
-anchor filaments of actin and myosin
32
What is cilia?
hair-like extensions
33
Are both cilia and flagella found on the surface of cells?
yes
note: not all cells have cilia or flagella
flagella is only found in aquatic organisms or sperm (tail)
34
What does flagella do?
propel the cell in one direction
35
Are ribosomes membranous or non-membranous?
non-membranous
36
Ribosomes are made up of _____ subunits with RNA and protein. Ribosomes can be free (SER) or attached to ER (RER). Ribosomes string amino acids together. What is this called?
2 (large and small), protein synthesis
37
The SER can take in glucose and make what?
starches, glycogen, etc
38
Are the RER and SER continuous with each other?
yes
39
The SER makes _____________________ and stores it in cisternae
carbohydrates/lipids
40
The RER is a network of cisternae (like a storage unit) that is synthesizing, making, and storing.....
macromolecules/proteins
41
What are the 2 faces of the golgi body called?
cis face
-way into golgi
-biggest ring/bottom of the stack
trans face
-way out of the golgi
-smallest ring/top of the stack
42
Are lysosomes membranous or non-membranous?
membranous
43
Lysosomes bud off from where?
golgi membrane (lysosomes are continually being made by the golgi)
44
Lysosomes contain what type of enzymes?
digestive enzymes
lysosomes can take something in and digest it because of these enzymes (similar idea to phagocytosis)
45
Lysosomes may fuse with vesicles formed at the....
plasma membrane
46
Lysosomes can be instructed to burst/lysis (due to _______________________) and destroy and digest the entire cell (self destruct)
toxins or cant keep up
47
Peroxisomes are small, round circles/vesicles that are capable of breaking down ________ nonpolar molecules
large
48
Peroxisomes are structures that are similar in shape to lysosomes, but are smaller and contain enzymes that use oxygen to oxidize (break down) organic substances. Peroxisomes contain enzymes that break down fatty acids and amino acids (peptides) by oxidizing cell substances. What does oxidization do to the cells? What molecule oxidizes?
ages it/damages it
free radicals are ions or molecules that oxidize cell
49
What do antioxidants do in the case of free radicals and peroxisomes?
antioxidants = against oxygen
so antioxidants mop up free radicals to prevent aging/damage in the cells
50
Proteasomes are barrel-shaped structures that destroy unneeded, damaged, or faulty proteins by cutting long proteins into smaller proteins so that it can be taken over by _____________ or ____________ to break it down more/destroy it
peroxisomes, lysosomes
51
Most oxidation processes that are carried out by peroxisomes produce hydrogen peroxide. What does hydrogen peroxide do?
oxidizes more things!
52
What shape is the mitochondria?
rod shape
53
Is the mitochondria membranous or non-membranous?
membranous!
2 membranes: outer and inner membrane
54
The inner mitochondrial membrane is saturated with what?
enzymes to do chemical reactions
55
The mitochondria has a double membrane system. The inner membrane contains many folds called the __________. What forms in the inner compartment of the mitochondria?
cristae, ATP
56
What does the outer membrane of the mitochondria allow for?
stockpiling of hydrogen ions and the formation of ATP
57
Mitochondria contains DNA (mtDNA) and ________________
ribosomes
58
mitochondria is roughly the size of what?
bacteria
59
metabolism is....
the sum of all reactions
60
Fuel goes into the mitochondria, which is glucose and holds energy inside of the carbon bonds.
Oxygen is also released into mitochondria.
The mitochondria will release ATP, ____________, and ________.
ATP goes on to do work inside of the cell, which is anything active, or any chemical reaction
carbon dioxide, heat
61
What is the purpose of the nuclear pore?
to increase transport and exchange
62
What are the 5 main parts of the nucleus?
1) nuclear envelope (double layered membrane)
2) nucleolus
3) nucleoplasm (cytoplasm of the nucleus)
4) chromatin (unfolded DNA)
5) chromosomes
63
What does the nucleolus contain?
RNA and proteins
64
The nuclear membrane controls what goes in and out of the nucleus. It keeps _______ from getting entangled in the cytoplasm and allows DNA to replicate
DNA
65
How many pairs of chromosomes do we have?
23 pairs, 46 in total
1-22 are given a number
chromosome 23= sex chromosomes
xx= female
xy= male
66
What are histones?
helper proteins that assist the DNA to be unwound
67
DNA is a long strand of nucleotides that makes up a recipe to make proteins. Chromatin is ____________________. Chromosomes is packaged DNA
DNA folded around histones
68
The nucleus contains the cells hereditary units, called __________, which are arranged in chromosomes
genes
69
The nucleolus is the site where some proteins and RNA combine to make the.....
ribosomal subunits
70
How do ribosomes leave the nucleus?
through pores
71
What do all tissues have?
cells and an ECF or ECM
(the proportion of cell and matrix varies among the 4 tissue types)
72
What does epithelial tissue do?
-lines, wraps, and covers
-covers exposed surfaces
-lines internal passageways
-forms glands
73
Which tissue type is the largest category?
connective tissue
74
What does connective tissue do?
-fills internal spaces
-supports other tissues
-transports materials
-stores energy
75
What does muscle tissue do and where is it found?
-specialized for contraction
-found in skeletal muscle, heart muscle, and the walls of hollow organs
76
What does neural tissue do?
carries electrical signals from one part of the body to another
77
Epithelial tissues are composed of closely aggregated _____________/__________ cells adhering strongly to one another and to a thin layer of ECM (basal lamina), forming cellular sheets that line the cavities of organs and cover the body surface
polyhedral/cuboidal
78
Epithelial tissue lines, wraps, and covers, or forms....
secretory tissues/glands
79
What tissue is this?
All external and internal surfaces of the body and all substances that enter or leave an organ must cross this type of tissue
epithelial tissue
80
Glands are __________ epithelial tissue (produce secretions)
modified
81
What are the rules/characteristics of epithelia?
1) cellularity (cell junctions)
2) polarity (apical surface = top of cell, basal= bottom of cell)
3) attachment (basal lamina, the foundation)
4) avascularity (no blood vessels, oxygen and nutrients will get through diffusion)
5) regeneration (cell division, will maintain the ability to undergo mitosis)
82
What other name is interchangeable with basal lamina?
basement membrane
83
The basal surface of all epithelia rests on a thin extracellular, felt like sheet of macromolecules referred to as the....
basement membrane
84
Glycoproteins and other components will often be stained and visualized with the light microscope of what structure?
basement membrane
85
The basal lamina is closest to the cells and contains what 3 things?
1) type IV collagen
2) laminin (glycoprotein that attaches to integrins)
3) nidogen and perlecan (gives structure and controls permeability)
86
What collagen is a part of the basal lamina?
type IV collagen
87
The basal lamina contains laminin. What is this?
its a glycoprotein that attaches to integrins for cell to cell adhesion
88
The basal lamina contains nidogen and perlecan for what purpose?
structure and permeability control
89
What is the difference between:
-tight/occluding/zonulae occludens junctions
-adherent/anchoring/zonula adherens junctions
-and gap junctions?
tight/occluding/zonulae occludens junctions form a seal between adjacent cells
adherent/anchoring/zonula adherens junctions are sites of strong cell adhesion
gap junctions are channels for communication between adjacent cells
90
Tight junctions/occluding/zonulae occludens are the most __________ of the junctions. The adjacent membranes at these junctions appear fused or very tightly apposed. Tight junctions ensure that molecules crossing an epithelium go through the cell, not between
apical
91
Adherent/anchoring/zonula adherens junctions encircle epithelial cells, usually immediately below the ____________ junction. They function like plastic bands that hold a 6-pack of canned drinks together
tight junctions/occluding/zonulae occludens
92
Desmosomes/macula adherens form a single spot weld and attach internally to....
intermediate filaments
note: hemidesmosomes also exist (1/2 of desmosome)
93
Gap junctions mediate _______________ communication rather than adhesion or occlusion between cells.
intercellular
94
Gap junctions consist of aggregated ________________ protein complexes that form circular patches in the plasma membrane. The proteins are ____________ and form pores 1.5nm diameter
transmembrane, connexins
95
Gap junctions permit intercellular exchange of....
molecules
96
In heart and visceral muscles, gap junctions help produce what?
rhythmic contractions
97
Define syncytium
cells working together as a "sheet", all do the same thing at same time
98
The apical ends of many columnar and cuboidal epithelial cells have specialized structures projecting from the cells. These function either to increase the apical ______________ for better absorption or to move substances along the epithelial surface
surface area
99
Microvilli are finger like extensions of the epithelial surface and each microvillus contains....
bundled actin filaments
100
In epithelia specialized for absorption, the apical cell surfaces are often filled with an array of projecting....
microvilli
101
absorption = in
secretion = ?
out
102
What do microvilli need?
cytoskeleton (microfilaments- actin)
103
Stereocilia are very long projections and are fairly rare, it is a much less common type of apical process that is best seen on the absorptive epithelial cells lining what system? What does stereocilia do here?
male reproductive system
stereocilia increases the cells surface area, facilitating absorption
104
Stereocilia is usually found in the male reproductive system but can also be found with a motion detecting function where?
in the inner ear sensory cells
105
Stereocilia resemble microvilli in containing arrays of _________________, ________________, and ___________________ but are typically much longer and less motile than microvilli
microfilaments, microtubules, actin-binding proteins
106
Cilia are long hair like, highly motile apical structures that are larger than microvilli. What are cilia powered by?
ATP
107
Cilia contain internal arrays of....
microtubules NOT microfilaments
cilia needs microtubules!
108
Motile cilia are abundant on what cells of epithelia?
cuboidal or columnar cells
109
T/F: cilia exhibit rapid beating patterns that move a current fluid and suspended matter in multiple directions along the epithelium
FALSE
cilia does this BUT in one direction only
110
The long flagellum that extends from each fully differentiated _______ cell has an internal structure like that of a cilium and move with a similar mechanism
sperm
111
What are the 4 functions of epithelial tissue?
1) provide physical protection
2) control permeability
3) provide sensation
4) produce specialized secretions
112
Epithelia can be divided into 2 main groups. What are they?
1) covering or lining epithelia
2) secretory or glandular epithelia
113
Cells of covering epithelia are organized into ____ layers that cover the surface or line the cavities of an organ
1+
114
What are the 2 classes of epithelia?
1) shape (squamous, cuboidal, columnar)
2) layers (simple, stratified)
115
What is the naming rule for epithelia?
always a 2 part name
1st layers, 2nd shape
116
What is simple squamous epithelium good for?
absorption and diffusion
ex: gas exchange through the alveoli
117
The apical layer is also known as the....
functional layer
118
What is stratified squamous epithelium good for?
protection
ex: oral cavity
119
Simple squamous epithelia is a single layer of thin cells, in which the cell nuclei are the ________ part of the cell and the most visible structures. Simple epithelia are typically specialized as lining of vessels and cavities, where they regulate passage of substances into the underlying tissue
thickest
120
What is mesothelium?
simple squamous epithelium that lines body cavities and secretes serous fluid
121
What is endothelium?
simple squamous epithelium that lines the heart and blood vessels
122
What are the 2 named epithelia in the human body?
mesothelium and endothelium
123
Simple cuboidal epithelium have a greater thickness than simple squamous epithelium and this allows cytoplasm to be rich in ____________ and other organelles for a high level of active transport across the epithelium and other functions. Simple cuboidal epithelium also allows for absorption and diffusion
mitochondria
124
Where is simple cuboidal epithelium found?
test q
-renal collecting tubule (a part of the nephrons)
-large thyroid follicle (in the thyroid gland)
-thick mesothelium covering an ovary
125
Does simple columnar have apical cilia or microvilli?
yes, helpful with absorption
126
What junctions are found within simple columnar epithelium?
tight and adherent junctions (present at the apical ends)
127
Where is simple columnar epithelium found?
test q
-renal collecting duct
-uterine tube
-lining of a gallbladder
128
Stratified squamous epithelia usually has protective functions. What are they?
-protection against easy invasion of underlying tissue by microorganisms
-protection against water loss
129
What are the 2 types of stratified squamous epithelium?
stratified squamous keratinized epithelium and stratified squamous nonkeratinized epithelium
130
Where is stratified squamous keratinized epithelium usually found and what is its function?
mainly in the epidermis of the skin, where it helps prevent dehydration from the tissue
131
Where is stratified squamous nonkeratinized epithelium usually found?
lines most internal cavities such as the mouth, esophagus, and vagina
132
What stratified epithelia are rare?
stratified cuboidal and stratified columnar
133
Where is transitional epithelium usually found?
urinary tract (bladder and ureters)
134
Name this epithelium:
Allows distension, tolerates repeated cycles of stretching and recoiling and returns to its previous shape without damage, as needed
transitional epithelium
135
Name this epithelium:
Tall, irregular cells all are attached to the basement membrane but their nuclei are at different levels and not all cells extend to the free surface.
pseudostratified epithelium
136
Where is pseudostratified epithelium found?
upper respiratory tract where the cells are also heavily ciliated (trachea)
137
Epithelial cells that function mainly to produce and secrete various macromolecules comprise specialized
organs called...
glands
138
secretory cells may synthesize, store, and release....
-proteins (ex: enzymes and hormones from pancreas)
-lipids (ex: hormones from adrenal gland or oils from sebaceous gland)
-carbs and proteins (ex: salivary glands)
139
Scattered secretory cells, sometimes called unicellular glands are common in what tissue(s)?
simple cuboidal, simple columnar, and pseudostratified epithelia
ex: goblet cells are abundant in the lining of the small intestine
