Cell Flashcards
1
Q
In 1665, ____ used a microscope to examine a thin slice of cork
A
Robert Hooke
2
Q
In 1673, _____ was first to view living organisms
A
Leeuwenhoek
3
Q
In 1838, a German botanist named ____ concluded that all plants were made of cells
A
Matthias Schleiden
4
Q
In 1839, a German zoologist named _____ concluded that all animals were made of cells
A
Theodore Schwann
5
Q
___&___ are the cofounders of the cell theory
A
Theodore Schwann
Matthias Schleiden
6
Q
In 1855, a German medical doctor named ____ observed cell dividing under the microscope and reasoned that all cells come from pre-existing cells by cell division
A
Rudolph Virchow
7
Q
The three postulates of the cell theory are?
A
All living things are made of cells
Cells are the basic unit of structure and function in an organism
Cells come from pre-existing cells through cell division
8
Q
The two types of cells are?
A
Prokaryotes
Eukaryotes
9
Q
Cells that lack a nucleus or membrane bound organelles are called?
A
Prokaryotes
10
Q
Four features of prokaryotes are?
A
Single circular chromosome
Nucleoid region
Surrounded by cell membrane and cell wall
Contain ribosomes
11
Q
The two types of cells are?
A
Prokaryotes
Eukaryotes
12
Q
Cells that lack a nucleus or membrane bound organelles are called?
A
Prokaryotes
13
Q
Four features of prokaryotes are?
A
Single circular chromosome
Nucleoid region
Surrounded by cell membrane and cell wall
Contain ribosomes
14
Q
Cells that have a nucleus or membrane bound organelles are called?
A
Eukaryotes
15
Q
Example of prokaryotes are?
A
Bacteria
16
Q
Examples of Eukaryotes are?
A
Protists
Fungi
Plants
Animals
17
Q
Three main features of eukaryotes are?
A
Nucleus
Cell membrane
Cytoplasm with membrane bound organelles
18
Q
Two main types of Eukaryotic cell are?
A
Plant cell
Animal cell
19
Q
Four features of organelles are?
A
Microscopic
Perform various cell functions
May or not be membrane-bound
Found in the cytoplasm
20
Q
Some examples of cell organelles are?
A
Cell or plasma membrane Lysosome Ribosome Endoplasmic reticulum Nucleus Golgi bodies Centrioles Mitochondria
21
Q
The cell/plasma membrane is composed of____&____
A
Double layer of phospholipids
Proteins
22
Q
Two functions of cell membrane are?
A
Protection
Selective permeability
Allow cell recognition
Anchoring sites for cytoskeleton filaments
23
Q
Phospholipids heads contain glycerol & phosphate and are _____
A
Hydrophilic
24
Q
Phospholipids tails are made of fatty acids and are ____
A
Hydrophobic
25
Phospholipids make up a ____ where tails point inward toward each other
Lipid Bilayer
26
Phospholipids can move ___ to allow small molecules(CO2, O2 & H2O)
Laterally
27
____ help move large molecules or aid in cell recognition
Cell membrane proteins
28
Two types of cell membrane proteins are?
Peripheral
| Integral
29
____are attached on the inner or outer surface of the cell membrane
Peripheral proteins
30
___ are embedded completely through the memebrane
Integral proteins
31
Jelly-like substance enclosed by cell membrane is called?
Cytoplasm
32
Two functions of cytoplasm are?
Provides a medium for chemical reactions to take place
| Contains organelles
33
The cell organelle bounded by a nuclear envelope/membrane with pores is called?
Nucleus (usually the largest organelle)
34
Two function of the nucleus are ?
Control and coordinate all the activities of the cell
| Contains DNA in chromosomes
35
A double membrane surrounding the nucleus is called?
Nuclear envelope/memebrane (contains nuclear pores for materials to enter and leave the nucleus)
36
DNA appears as _____ in non-dividing cells
Chromatin
37
DNA is condensed and wrapped around proteins to form?
Chromosomes
38
____ is the hereditary material of the cell
DNA
39
The organelle that makes ribosomes inside the nucleus is called?
Nucleolus(disappears when cell divides)
40
The functions of the cytoskeleton are?
It helps cell maintain cell shape
| It helps move organelles around
41
Cytoskeleton a is made up of____, ____&____
Proteins
Microfilaments(threadlike, made of actin)
Microtubules (tubelike, made of tubulin)
42
The organelle found in animal cells only is?
Centrioles
43
The function of centrioles is?
To form mitotic spindle to pull chromosome pairs apart to opposite ends of cells
44
The site of cellular respiration in the cell is?
Mitochondria
45
Two features of mitochondria are?
Cristae(folded inner membrane)
| Matrix(interior)
46
Mitochondria are inherited from your ____
Mother(egg cell)
47
Network of hollow membrane tubules connected to nuclear envelope & cell membrane is called?
Endoplasmic reticulum
48
Two functions of endoplasmic reticulum are?
Synthesis of cell products
| Transport
49
Two kinds of Endoplasmic reticulum are?
Rough
| Smooth
50
Rough endoplasmic reticulum makes?
Membrane proteins and proteins for export out of cell
51
Smooth endoplasmic reticulum makes?
Makes membrane lipids(steroids)
Regulates calcium (muscle cells)
Destroys toxic substances (liver)
52
The main difference between rough and smooth endoplasmic reticulum is?
Presence of ribosomes on the surface of rough endoplasmic reticulum
53
Ribosomes are made up of ___&___
Proteins
| rRNA
54
Function of ribosomes is
Protein synthesis
55
Ribosomes are either attached to the _____ or free in the ____
Rough ER
| Cytoplasm
56
Sacks of flattened sacks having a CIS face and a TRANS face is called?
Golgi bodies
57
The shipping side of Golgi bodies is called?
CIS face
58
The receiving side of Golgi bodies is called?
Trans face
59
Function of Golgi bodies is?
Modify, sort and package molecules from ER for storage or transport out of the cell
60
Materials are transported from the Rough ER to Golgi bodies to the cell membrane by ____
Vesicles
61
Two functions of lysosomes are?
Break down food, bacteria and worn out cell parts
| Programmed for cell death(Apoptosis?
62
Function of cilia/flagella is?
Moving cells, fluids or small particles across the cell membrane
63
___ are shorter and more numerous on cells
Cilia
64
___ are longer and fewer on cells(usually 1-3)
Flagella
65
The basic functional and structural unit of various tissues and organs is called?
Cell
66
The human body has ____ cells
75-100 trillion
67
The chemical composition of the cell is?
```
Water(70-85%)
Proteins(10-20%)
Ions(sodium, potassium etc)
Lipids(2%)
Carbohydrates
```
68
The chemical composition of cell membrane is
Proteins(55%)
Lipids(42%)
Carbohydrates(3%)
69
The cell membrane is about ___ in size
75-100A°
70
Classification of cell membrane proteins are?
Structural proteins(glycoproteins & lipoproteins)
Pumps( transport ions across the membrane)
Receptors( binds hormones and neurotransmitters)
Carriers(transport various substances by facilitated diffusion)
Enzymes(peripheral proteins)
Ion channels(integral proteins)
71
G
```
Cell or plasma membrane
Lysosome
Ribosome
Endoplasmic reticulum
Nucleus
Golgi bodies
Centrioles
Mitochondria
```
72
In the fluid mosaic model of cell membrane, FLUID depicts
Free movement of phospholipids and proteins within the membrane like a liqiud
73
In the fluid mosaic model of cell membrane, MOSAIC depicts
The pattern produced by the scattered protein molecules when the membrane is viewed from above
74
The type of transport in the cell membrane that doesn't require energy and moves due to gradient is called?
Passive Transport
75
Examples of gradient are?
Concentration
Pressure
Charge etc
76
Types of passive transport are?
Diffusion
Osmosis
Facilitated diffusion
77
The movement of molecules to equalise gradient (high to low)
Diffusion
78
The movement of fluid from lower concentration to higher concentration through semi-permeable membrane is?
Osmosis
79
Solvent + Solute =?
Solution
80
A solution that has more solutes in the cell than outside is called?
Hypotonic solution (outside solvent flows into the cell)
81
A solution that has equal amount of solutes inside and outside of the cell is called?
Isotonic solution
82
A solution that has more solutes outside the cell than inside is called?
Hypertonic( fluid will flow out of the cell)
83
The transport of molecules and ions via transmembrane integral proteins(channels? through differentially permeable membrane is called?
Facilitated diffusion
84
Process of facilitated transport includes
Protein binds with molecules
Shape of protein changes
Molecules move across membrane
85
The type of transport that requires energy is called?
Active transport
86
Two types of active transport are?
Primary active transport
| Secondary active transport
87
Materials transported by active transport are either in ____ or ____
```
Ionic form(sodium, potassium, calcium etc)
Non-ionic form(glucose, amino acid etc)
```
88
The type of active transport in which energy is liberated directly from ATP breakdown is called?
Primary active transport
89
Active transport of sodium requires ___
sodium-potassium ATPase pump
90
Sodium potassium ATPase pump has 2 subunits namely?
Alpha subunit
| Beta subunit
91
Sodium potassium pump has 6 receptor sites namely?
3 receptor sites for sodium ion from the inner surface
2 receptor sites for potassium ion from the outer surface
1 receptor site for the enzyme ATPase
92
Calcium is transported by the?
Calcium pump(obtains energy from ATP breakdown)
93
Calcium pumps are present in____ of all cells and mitochondria
Sarcoplasmic reticulum
94
Hydrogen is transported by?
Hydrogen pump(obtains energy from ATP breakdown)
95
Hydrogen pump is present in organs like?
Stomach(parietal cells of gastric glands)
| Kidney(in epithelial cells of distal tubules
96
The type of active transport in which substances are transported with sodium ion by means of a carrier protein in the same or opposite direction is called?
Secondary active transport
97
Two types of secondary active transport are?
Cotransport
| Countertransport
98
A carrier protein that transports 2 different molecules in the same direction across the cell membrane is called?
Symport
99
Example of Symport is?
Transport of sodium and glucose
| Transport of sodium and amino acids
100
A carrier protein that transports 2 different molecules in opposite direction across the cell membrane is called?
Antiport
101
Example of Antiport is?
Sodium calcium countertransport
Sodium magnesium countertransport
Sodium hydrogen countertransport
102
Three special types of active transport are?
Endocytosis
Exocytosis
Transcytosis
103
Special active transport move large materials like?
Particles
Organisms
Large molecules
104
Movement of large molecules into cells is called?
Endocytosis
105
Two types of endocytosis are?
Bulk-phase(non-specific)
| Receptor-mediated(specific)
106
The process of endocytosis include?
Plasma membrane surrounds material
Edges of membrane meet
Membranes fuse to form vesicle
107
Two forms of endocytosis are?
Phagocytosis(cell eating)
| Pinnocytosis(cell drinking)
108
Movement of large molecules out of cell is called?
Exocytosis
109
Process of exocytosis is?
Vesicle moves to cell surface
Membrane of vesicle fuses
Molecules expelled
110
The communication between neighbouring cells or the contact between the cell and the extracellular matrix is called?
Cell junction
111
Three types of cell junctions are?
Occluding junctions
Anchoring junctions
Communicating junctions
112
The cell junction that seals cells together into sheets(forming an impermeable barrier) is
Occluding junction/tight junctions
113
The cell junction that attach cells and their cytoskeleton to other cells or extracellular matrix (providing mechanical support) is?
Anchoring junctions
114
The cell junction that allows exchange of chemical/electrical information between cells is called?
Communicating junctions
115
Cell to cell connections are mediated by?
Cadherins
116
Cadherins participate in?
AdherenS junctions
117
Tight junctions proteins are?
Claudin
| Occludin
118
___ allow cells to exchange electrical/chemical signals
Gap junctions
119
Gap junctions channels subunits are?
Connexins
120
Connexins assemble together to form?
Connexons
121
Connexons from two cells form a?
Gap junction
122
How do cells alter their connections to other cells?
Alter the profile of cytoskeletal connections, receptors and extracellular matrix
Alter the binding affinity of receptors
123
Receptors are mostly ____ dependent
Ca2+
124
Receptors are mostly affected by____
Protein kinases
125
___ joins the intermediate filaments in one cell to those in a neighboring cell
Desmosome
126
___allows passage of small water soluble ions and molecules
Gap junction
127
____ anchors intermediate filaments in a cell to the basal lamina
Hemidesmosome
128
___ seals neighboring cells together in an epithelial sheet to prevent leakage of molecules between them
Tight junction
129
___ allow cells to exchange electrical/chemical signals
Gap junctions
130
Gap junctions channels subunits are?
Connexins
131
Connexins assemble together to form?
Connexons
132
Connexons from two cells form a?
Gap junction
133
How do cells alter their connections to other cells?
Alter the profile of cytoskeletal connections, receptors and extracellular matrix
Alter the binding affinity of receptors
134
Receptors are mostly ____ dependent
Ca2+
135
Receptors are mostly affected by____
Protein kinases
136
___ joins the intermediate filaments in one cell to those in a neighboring cell
Desmosome
137
___allows passage of small water soluble ions and molecules
Gap junction
138
____ anchors intermediate filaments in a cell to the basal lamina
Hemidesmosome
139
___ seals neighboring cells together in an epithelial sheet to prevent leakage of molecules between them
Tight junction
140
____ is also known as zona occludenn
Tight junction
141
The two types of proteins involved in the formation of tight junctions are?
Integral membrane proteins: occludin,claudin, JAM's
| Scaffold proteins:cinguilin,symplekin
142
JAM's mean?
Junctional adhesion molecules
143
Four functions of tight junctions are?
Strength and stability
Fencing function
Blood-brain barrier
Selective permeability
144
Four disease caused by tight junction protein's genes mutations are?
Hereditary deafness
Ichthyosis (scary skin)
Synovial sarcoma (soft tissue cancer)
Sclerosing cholangitis (inflammation of bile ducts?
145
Two types of anchoring junctions are?
Actin filament attachment
| Intermediate filament attachment
146
Two types of actin filament(MF) attachment are?
```
Cadherins (cell to cell)
Focal adhesion (cell to matrix)
```
147
Two types of intermediate filament(IF) attachment are?
Desmosomes (cell to cell)
| Hemidesmosomes(cell to matrix)
148
Dysfunction of the cadherins and focal adhesion junctions due to protein mutations causes ___&___
Colon cancer
| Tumor metastasis
149
Dysfunction of hemidesmosomes causes?
Bullous pemphigoid
150
Connexons are either___ or ___
Homomeric
| Heteromeric
151
Gap junction intercellular channels are either____ or ____
Homotypic
| Heterotypic
152
Three functions of gap junctions include?
Exchange of chemical messengers between the cells
Rapid propagation of action potential from one cell to another
Allows passage of glucose, amino acids and other substances with a molecular weight less than 1000
153
Factors that regulate the diameter of gap junctions are?
pH
Electrical potential
Hormones or neurotransmitters
Calcium ion concentration
154
Mutations of genes encoding connexins causes diseases like?
```
Deafness
Keratoderma
Cataract
Peripheral neuropathy
Heterotaxia
```
155
Maintenance of a relatively stable internal environment is called?
Homeostasis
156
Maintenance of homeostasis is carried out by?
Nervous system
| Endocrine system
157
The nervous system regulates homeostasis by?
Controlling and coordinating bodily activities that require rapid responses
Detects and initiates reactions to changes in external and internal environment
158
The endocrine system regulates homeostasis by?
Releasing hormones
159
Homeostasis is continuously disrupted by?
```
External stimuli (heat, cold, toxins etc)
Internal stimuli(body temperature, blood pressure, water and glucose concentration etc)
```
160
Components of homeostasis system are?
```
Sensors) receptors
Comparator/control centre
Effectors
Feedback control
Communication system
```
161
Sensors) receptors detects?
Changes in the internal environment
162
Comparator/control centre fixes?
The set point of the system
163
The function of effectors is to?
Bring the system back to the set point
164
Two types of feedback control are?
Positive feedback
| Negative feedback
165
Positive feedback/positive feedback loop ____ the original stimulus
Intensifies/increases
166
Negative feedback/negative feedback loop ____ the original stimulus
Reverses/shuts off
167
Example of positive feedback loop is?
Childbirth
168
Example of negative feedback loop is?
Most feedback systems in the body eg blood pressure
169
A homeostatic control system must be able to?
Receive signal from the receptor
Integrate this information with other relevant information
Send a signal to the appropriate organ or gland to make the necessary adjustment
Sense deviations from the norm itself
170
The general control centre for homeostasis is the?
Brain(hypothalamus)
| The pancreas is it's own control centre for blood sugar
171
___ are responses made after change has been detected
Feedback
172
```
In blood pressure system (negative feedback) march the following?
Stimulus-___
Receptor/sensor-___
Control centre/comparator-___
Effector-___
```
Blood pressure
Baroreceptors
Brain(hypothalamus)
Heart
