Chapter 4 Flashcards
1
Q
What was the first step toward understanding the importance of cells?
A
Their discovery in the 1600s
2
Q
All cells come from previously existing cells and consists of three principles
A
- Every organism is made up of one or more cells
- The smallest organisms are single cells, and cells are the functional units of multicellular organisms
- All cells arise from preexisting cells
3
Q
Who developed a primitive light microscope?
A
English scientist Robert Hooke.
Year: 1665
4
Q
Robert Hooke viewed a very thin piece of
A
cork and saw “a great many little boxes,” which he drew
5
Q
Light microscopes can view
A
living cells
6
Q
In the 1670s,
A
Anton van Leeuwenhoek built his own microscope
7
Q
Light microscopes use lenses made of
A
glass or quartz to bend and focus light
8
Q
Light microscopes
A
use lenses made of glass or quartz to bend and focus light
9
Q
Electron microscopes provide
A
high resolution
10
Q
Electron microscopes use beams of electrons focused
by
A
magnetic fields to resolve images
11
Q
Transmission electron microscopes pass electrons
through a
A
thin specimen
12
Q
Scanning electron microscopes
A
bounce electrons off
specimens that are dry and hard
13
Q
Genetic material is contained
within a membrane-enclosed structures
A
In Eukaryotic cells
14
Q
Eukaryotic cells
A
are complex and make up the
bodies of animals, plants, fungi, and protists
15
Q
Prokaryotic cells
A
do not have a nucleus
16
Q
The single cells of bacteria and archaea, the simplest
forms of life, are
A
prokaryotic
17
Q
Most cells range in size from about
A
1 to 100
micrometers (millionths of a meter) in diameter
18
Q
All cells are descended from an ancestor that arose about
A
3.5 billion years ago
19
Q
Cells are so small, so they can
A
exchange nutrients and wastes with their external environment
20
Q
a process by which molecules dissolved in fluids move, is relatively slow
A
Diffusion
21
Q
All parts of the cell must remain close to the external environment to have access to
A
nutrients and be able to get rid of wastes
22
Q
The plasma membrane encloses the cell and allows
A
interactions between the cell and its environment
23
Q
Each cell is surrounded by a thin membrane called the
A
plasma membrane
24
Q
The plasma membrane consists of proteins embedded in a
A
bilayer of phospholipids
25
allow specific molecules to pass into or out of the cell
Channel proteins
26
bind messenger molecules and initiate a cell’s response to the message
Receptor proteins
27
All cells contain
cytoplasm
28
The cytoplasm consists
of all the fluid and
structures inside the plasma membrane but
outside the nucleus in eukaryotes
29
The fluid portion of the cytoplasm is called
cytosol
30
The cytosol contains
water, salts, and organic molecules (protein, carbohydrates and lipids. Sometimes RNA it depends)
31
The cytoskeleton consists of a variety of
protein filaments
32
protein filaments
provide support, transport structures within the cell, and
| allow cells to move and change shape
33
protein filaments also play a role in
cell division
34
All cells use D N A as
hereditary instructions to form RNA
35
R N A guides construction of
cell parts/proteins
36
The genetic material in all cells consists of
deoxyribonucleic acid (D N A)
37
D N A encodes an inherited set of instructions in segments called
genes
38
Genes store the instructions for making
all the parts of a cell and for producing new cells
39
D N A genes are copied to
ribonucleic acid (R N A)
40
R N A is chemically similar to
D N A
41
RNA
helps construct proteins based on genetic instructions
42
The proteins are constructed on
ribosomes, cellular workbenches of specialized R N A called ribosomal R N A
43
Prokaryotic cells have a relatively simple
internal structure
44
Prokaryotic cells are generally less than
5 micrometers in diameter
45
Prokaryotes are unicellular and make up two of life’s
| domains
Archaea and Bacteria
46
Prokaryotic cells have specialized
cytoplasmic structures
47
A distinct region called the
nucleoid contains a single circular chromosome that consists of a long, coiled strand of D N A
48
plasmids
small rings of D N A
49
Most Prokaryotic cells
feature small rings of D N A called plasmids in addition to the nucleoid
50
Prokaryotic cells have distinctive
surface features
51
Nearly all prokaryotic cells are surrounded by a
cell wall
52
The cell wall provides protection and helps the
prokaryotic cell maintain its shape
53
Prokaryotic cell shape
may be rod-like, spiral, or spherical
54
Gram+ve
thick peptidoglycan layer. Layer retains the dye crystal violet. Plus it has teichoic acid.
55
Gram–ve
thin layer of peptidoglycan layer in the periplasmic space and contains a thick lipopolysaccharide layer, which prevents the crystal violet color to be retained by the cell. Cells can be seen by counterstain Safranin red dye.
56
Bacillus anthrax is a
gram positive bacteria !
Vegetative cells (showing the retention of crystal violet) can produce spores that survive about 48 years or more !
57
Pili (singular, pilus) are surface proteins (pilin) that
that project from the cell walls of many bacteria
58
Attachment pili
help bacteria
| adhere to surfaces
59
Sex pili
form connections
| between adjacent bacteria that allow them to transfer plasmids
60
Flagella rotate and propel the cell through the
fluid environment
61
Some bacteria and archaea possess
flagella (singular, flagellum), which extend from the cell surface
62
Flagellin protein is the principle component of
bacterial flagella
63
Eukaryotic cells make up the bodies of organisms in the
domain Eukarya
64
Eukaryotic cells contain
organelles
65
organelles
membrane-enclosed structures specialized for a particular function
66
Organelles contribute to the complexity of
eukaryotic cells
67
Extracellular matrix
Surrounds cells, providing biochemical and structural support
68
Is the extracellular matrix in prokaryotes?
Absent mostly. Formation of a biofilm can create an extracellular matrix.
69
Is the extracellular matrix in eukaryotes (plants)?
Yes
70
Is the extracellular matrix in eukaryotes (animals)?
Yes
71
Cilia
Move the cell through fluid or move fluid past the cell surface
72
Is cilia in prokaryotes?
no
73
Is cilia in eukaryotes (plants)?
Absent in higher plants.
74
Is cilia in eukaryotes (animals)?
Present
75
The sweeping motion of cilia (small hairs in the trachea)
keep air passages clean
76
Paramecium (are eukaryotic, unicellular) contains
numerous cilia around their body surface that co- ordinates the movement of cell
77
Flagella
Move the cell through fluid
78
Are flagella in prokaryotes?
Yes
79
Are flagella in eukaryotes (plants)?
Absent in higher plants.
80
Are flagella in eukaryotes (animals)?
Present
| (e.g. mammalian sperm cell)
81
Plasma membrane
Isolates the cell contents from the environment; regulates movement of materials into and out of the cell; allows communication with other cells
82
The plasma membrane is present in
prokaryotes and all eukaryotes
83
Nucleus
Contains chromosomes and nucleoli
84
Nuclear envelope
Encloses the nucleus; regulates movement of materials into and out of the nucleus
85
Nucleolus
Synthesizes ribosomes
86
Prokaryotes don't have a
nucleus, nuclear envelope, and nucleolus
87
All eukaryotes have a
nucleus, nuclear envelope, and nucleolus
88
Organization of Genetic Material in human white blood cells showing 23 pairs of chromosomes
(basic Karyotype staining)...RBC are enucleated
89
Genetic material
Encodes the information needed to construct the cell and to control cellular activity
90
Prokaryotes and all eukaryotes have
genetic material (DNA)
91
Chromosomes
Contain and control the use of DNA
92
The chromosomes in prokaryotes are
single, circular
93
The chromosomes in eukaryotes are
Many, linear
94
Ribosomes
provide sites for protein synthesis
95
Ribosomes are present in
prokaryotes and all eukaryotes
96
Mitochondria
produce energy by aerobic metabolism
97
Mitochondria is absent in
prokaryotes
98
Mitochondria is present in
all eukaryotes
99
Chloroplasts
perform photosynthesis and contains circular chloroplast DNA
100
Chloroplasts are absent in
prokaryotes and animal eukaryotes
101
Chloroplasts are present in
eukaryote plants
102
The Endoplasmic reticulum
synthesizes membrane components, proteins, and lipids
103
Endoplasmic reticulum is absent
in prokaryotes
104
Endoplasmic reticulum is present
in all eukaryotes
105
Golgi apparatus
modifies, sorts, and packages proteins and lipids
106
The Golgi apparatus is absent in
prokaryotes
107
The Golgi apparatus is present in
all eukaryotes
108
Lysosomes
contain hydrolytic enzymes; digest food and worn-out organelles
109
Lysosomes are absent in
prokaryotes and absent in most eukaryotic plants
110
Lysosomes are present in
eukaryotic animals
111
Lysosomes in human macrophage cell
eliminates bacteria
112
MHC’s (major histocompatibility complex) are important for
immune response in all the nucleated cell
113
Central vacuole
Contains water and wastes; provides turgor pressure to support the cell
114
The central vacuole is absent in
prokaryotes and eukaryotic animals
115
The central vacuole is present in
eukaryotic plants
116
Energy- Requiring Transport
Movement of substances through membranes using cellular energy, usually supplied by A T P
117
Diffusion is under
passive transport
118
Movement of individual small molecules or ions against their concentration gradients through membrane spanning Proteins
Active transport
119
Osmosis
diffusion of free water molecules
120
Cells maintain concentration gradients using
active transport
121
During active transport, membrane proteins use energy to move molecules or ions
against their concentration gradients
122
An ATP molecule consists of an
adenosine a nitrogenous base, a ribose sugar and tri-phosphate chain
123
The high-energy phosphate is key to ATP's
energy storage potential
124
ATP contains
3 phosphate molecules
125
Substances are transported from areas of
lower concentration to areas of higher concentration
126
Kinase enzyme breaks
ATP to ADP and transfers phosphate molecule to proteins
127
Movement of fluids, specific molecules, or particles into a cel
Endocytosis
128
occurs as the plasma membrane engulfs the substance in a membranous sac that pinches off and enters the cytosol
Endocytosis
129
Movement of particles or large molecules out of a cell
Exocytosis
130
Movement of molecules from an area of high concentration to an area of low concentration
Diffusion
131
occurs as a membrane within the cell encloses the material, moves to the cell surface, and fuses with the plasma membrane, allowing its contents to diffuse out
Exocytosis
132
In most animal cells, adenosine triphosphate (ATP) works as the main
carrier of chemical energy.
133
The human body uses three types of molecules to yield the necessary energy to drive ATP synthesis:
fats, proteins, and carbohydrates.
134
Do you need ATP for osmosis?
No
135
You need aquaporine
Can help.....
136
main site for ATP synthesis in mammals
Mitochondria
137
Some ATP is also synthesized in the
cytoplasm
138
Cell derives its energy from the
food we eat
139
What is broken down into fatty acids?
Lipids
140
Proteins break down into
amino acids
141
Carbohydrates break down into
glucose
142
What breaks down a glucose molecule and forms
| 2 pyruvate molecules, with the release of two molecules of ATP and 2 NADH
Glycolysis
143
Kreb’s Cycle occurs in the ________________ of the eukaryotic cell.
Mitochondria
144
Plants simply undergo photosynthesis first as a way to make
glucose
145
pyruvate formed is converted to Acetyl CoA which is the precursor molecule of
Kreb’s cycle
146
Animals don't need to photosynthesize since they get their glucose from the
food they eat.
147
You need a carrier protein to aid in
glucose entering cell.
148
we don’t have chloroplast or pigment chlorophyll like
plants and algae
149
Glucose to pyruvate it called
glycolysis
150
Glucose to pyruvate occurs in the
cytoplasm
151
Mitochondria is the main site where
ATP is formed
152
The Krabs cycle is in the
mitochondria of eukaryotic cells
153
__________ __________ is the process by which organisms break down glucose into a form that the cell can use as energy
Cellular respiration
154
_____________ is the main site where glycolysis occurs
Cytoplasm
155
Aerobic
process the requires oxygen
156
Anaerobic
process that doesn't require oxygen
157
Fermentation
an anaerobic
158
1st step of cellular respiration is the
breaking down of glucose into pyruvate
159
Krebs cycle cannot occur in the absence of
oxygen
160
Aerobic
glucose and oxygen
161
anaerobic
glucose
