Cell Flashcards
(140 cards)
1
Q
What is the size range of a typical plant cell?
A
10–100 µm
2
Q
What is the size of a chloroplast?
A
2–10 µm
3
Q
What is the length of Trypanosoma?
A
25 µm long
4
Q
What is the size of Chlamydomonas?
A
5–6 µm
5
Q
What is the size of Poliovirus?
A
30 nm
6
Q
What is the size of HIV (AIDS virus)?
A
100 nm
7
Q
What is the size range of a mitochondrion?
A
1–5 µm
8
Q
What is the diameter of a human red blood cell?
A
7–8 µm
9
Q
What is the size of a hen’s egg?
A
65 mm
10
Q
What is the size of a neuron cell body?
A
70 µm
11
Q
What is the size range of Escherichia coli?
A
1–5 µm long
12
Q
What is the diameter of a DNA molecule?
A
2 nm
13
Q
What is the length of T4 bacteriophage?
A
225 nm
14
Q
What is the length of Tobacco mosaic virus?
A
300 nm
15
Q
What is the length and diameter of an ostrich egg?
A
16–18 cm long, 13 cm diameter
16
Q
What is the size of the female egg cell?
A
117–142 µm
17
Q
What is the resolving power of a light microscope?
A
down to 200 nm
18
Q
What is the resolving power of an electron microscope?
A
down to 0.5 nm
19
Q
What percentage of total body cells are red blood cells (RBCs)?
A
Over 85%
20
Q
RBCs make up over ___% of total body cells.
A
85
21
Q
What is the diameter range of a red blood cell?
A
7–8 μm
22
Q
What is the thickness range of a red blood cell?
A
0.5–1 μm
23
Q
What are immature RBCs called?
A
Reticulocytes
24
Q
Why are immature RBCs called reticulocytes?
A
Because they have basophilic endoplasmic reticulum
25
Cell size is ___ proportional to SA:V ratio.
Inversely
26
Who proposed the cell theory? (Name all three)
Matthias Schleiden, Theodor Schwann, Rudolf Virchow
27
Antonie van Leeuwenhoek contributed to the discovery of
Cells
28
What type of cells have organelles not bound by membranes?
Procaryotic cells
29
List the membrane-unbound organelles in prokaryotic cells. 6
Flagellum, Basal body, Capsule, Cell wall, Plasma membrane, Ribosomes
30
What are the components of cytoplasm?4
Interconnected filaments & fibers, Cytosol, Organelles (excluding nucleus), Storage substances
31
Name the three fiber types of the cytoskeleton and their thickness.
Microfilaments (8nm), Intermediate filaments (10nm), Microtubules (25nm)
32
What are the three functions of the cytoskeleton?
Mechanical support, Anchor organelles, Help move substances
33
Cilia and Flagella are made up of what structures?
Bundles of microtubules (9 outer pairs & 2 central microtubules) covered with plasma membrane
34
What structures provide motility and are hair-like projections on the cell exterior?
Cilia and Flagella
35
What is the difference in function between cilia and flagella?
Cilia move substances outside human cells, Flagella provide movement (e.g., sperm cells)
36
Cilia are ____ and used to move substances outside human cells.
short
37
Flagella are ____ extensions found on sperm cells.
whip-like
38
The basal body is structurally similar to what organelle?
Centrioles
39
What is the microtubule organizing center of the cell?
Centrosome
40
Where is the centrosome located?
Near the nucleus
41
What is formed at the dense center of the centrosome?
Centriole
42
What does the centrosome do during mitosis?
It divides and the two parts move to opposite sides of the dividing cell
43
____ directs synthesis of RNA
Nucleolus
44
What are centrioles composed of?
Pairs of microtubular structures
45
What is the function of the nucleolus?
It directs synthesis of RNA and synthesizes ribosomal RNA
46
Most cells have how many nucleoli?
One or more
47
Intracellular highway; which organelle?
Endoplasmic reticulum
48
Makes more ER and may modify proteins from ribosomes?
Rough ER
49
Are all ribosomes attached to the RER?
No
50
Makes lipids, breaks down toxins such as drugs/alcohol?
Smooth ER
51
Transmitting materials through the cell, containing enzymes, producing and digesting lipids and membrane proteins.. functions of?
ER lumen
52
The ER buds off to transport proteins and lipids to ____.
Golgi body, lysosomes, and membranes
53
What organelle produces membranes that surround lysosomes?
Golgi Apparatus
54
Which organelle packages proteins and carbohydrates into vesicles for export?
Golgi body
55
What additional role does the Golgi Apparatus have in plants?
Synthesis of plant cell wall
56
The Golgi body is often called the ____ and ____ of the cell.
Packaging, shipping station
57
List the 6 steps in Golgi Apparatus function.
Molecules come in vesicles → Vesicles fuse with Golgi → Molecules may be modified → Molecules pinched off → Vesicle leaves Golgi → Vesicle may fuse with plasma membrane to secrete contents
58
Aid in cell renewal, Break down old cell parts, Digests invaders Functions of?
Lysosomes
59
What organelle protects the cell from toxins like hydrogen peroxide?
Peroxisome
60
What is the structure of a peroxisome?
Membrane bound and contains enzymes
61
Vacuoles are more common in which type of cell?
Plant cells
62
What do vacuoles store?
Water, food, and wastes
63
Name the two bacteria-like organelles involved in energy.
Mitochondria and Chloroplasts
64
Which organelle releases energy? Which one stores
Mitochondria releases, Chloroplast stores
65
Describe the structure of mitochondria.
Bean-shaped, double membrane, has own DNA and ribosomes
66
What is the significance of cristae in mitochondria?
They are inner membrane folds that increase surface area for ATP production
67
What type of genetic material do mitochondria contain?
Own DNA
68
69
Approximately how many cell divisions occur in a human lifetime?
10 quadrillion
70
The essence of cell division is to maintain what?
Original cell genome
71
Who first discovered cell division under a microscope and in what year?
Hugo von Mohl in 1835
72
What organism was Hugo von Mohl studying when he discovered cell division under the microscope?
Green alga Cladophora glomerata
73
Who first filmed cell division microscopically and in what year?
Kurt Michel in 1943
74
What technology did Kurt Michel use to film cell division?
Phase-contrast microscope
75
Who found that gametes contain half the number of chromosomes compared to somatic cells, and in what year?
Pierre-Joseph van Beneden in 1882
76
What organism did Pierre-Joseph van Beneden study to discover differences in chromosome numbers?
Roundworm Ascaris
77
DNA Transcription into mRNA starts with the attachment of what enzyme to what structure?
RNA polymerase II to a core promoter
78
Transcription is initiated by unwinding the double helix of the DNA _____ turns.
Two
79
What does the enzyme use as a template to polymerize complementary bases of RNA?
Exposed DNA strands
80
As the enzyme moves along the DNA, what happens to the polymerized mRNA chain?
It is separated from the template DNA strand
81
Why do cells divide as they get bigger?
To efficiently transport materials in and out of the cell
82
What phase of mitosis involves the DNA recoiling and chromosomes condensing?
Prophase
83
During which phase do chromosomes line up in the middle of the cell?
Metaphase
84
In which phase do sister chromatids get pulled to opposite poles?
Anaphase
85
The actual splitting of the daughter cells into two separate cells is?
Cytokinesis
86
Mitosis organization phase
Metaphase
87
Mitosis preparation phase
Prophase
88
Mitosis separation phase
Anaphase
89
In _____: spindle fibers attach to chromosomes and chromosomes keep condensing.
Prometaphase
90
What are the stages of the cell cycle?
Interphase (G1, S, G2) and M phase (Mitosis + Cytokinesis)
91
What is the resting phase where the cell is not dividing?
G0 phase
92
During which substage of Prophase I does crossing over occur?
Pachytene
93
What structure forms the point of contact between homologous chromosomes during crossing over?
Chiasma
94
Chromosomes in thread like form are called
Chromatonemata
95
In chromatonemata, ___ of each chromosomes are tuned toward and attached to the same region of the nuclear envelope
telomeres
96
_____ is referred to the bouquet stage
Chromatonemata
97
____ is the interface where two homologs unite
Synaptonemal complex
98
Chiasma is formed in _____
Diplotene
99
What is the term for the movement of chiasmata toward the ends of chromatids?
Terminalization
100
What is the prolonged diplotene stage in oocytes called?
Dictyotene
101
What is the substage of Prophase I where the nuclear envelope disappears, terminalization reaches completion?
Diakinesis
102
What is the outcome of Meiosis I?
Two haploid daughter cells
103
At ___ point in __ phase, the cell is committed to division and moves into the S phase
Restriction point in G1 phase
104
Cellular constituents excluding the chromsomes are duplicated in ___ phase
G1 phase
105
Chromosomes become duplicated in ___ phase
S phase
106
____ is post-mitotic interphase substage
G1
107
Duration f cell cycle in rapidly dividing human cells is
24 hours
108
Duration of G1 phase
9 hours
109
Duration of S phase
10 hours
110
Duration of G2 phase
4.5 hours
111
Duration of Mphase
30 minutes
112
What is the term for a chromosome abnormality involving an extra or missing chromosome?
Aneuploidy
113
What syndrome is caused by trisomy of chromosome 21?
Down syndrome
114
What syndrome is caused by monosomy of the X chromosome?
Turner syndrome
115
What syndrome is caused by having 47 chromosomes (XXY)?
Klinefelter syndrome
116
What is the term for a chromosome abnormality involving a missing segment?
Deletion
117
What syndrome is associated with terminal deletion of 5p?
Cri du chat syndrome
118
What syndrome is associated with interstitial deletion of 11p?
Wilms tumor
119
What is the term for a chromosome abnormality involving a reversed segment?
Inversion
120
What syndrome is associated with a ring chromosome 18?
Mental retardation syndrome
121
What is the outcome of a fragile site on the X chromosome (Fragile X)?
Mental retardation syndrome
122
What is the term for a chromosome abnormality involving exchange of segments between nonhomologous chromosomes?
Translocation
123
What is the term for a translocation involving fusion of two acrocentric chromosomes?
Robertsonian translocation
124
What is associated with pericentric inversion on chromosome 9
Normal phenotype
125
Isochromosome X (fusion of long arms with loss of short arms) is an example of ___ and the outcome is ____
Duplication; Infertility in females
126
Robertsonian translocation can lead to major abnormalities including ___ and ____
Physical and mental handicaps
127
Reciprocal unbalanced translocations may cause abnormalities due to ___ or cause ____
disruption of genes; subjections to physical and mental handicaps
128
What is the structure that contains genetic information and is made up of DNA and proteins?
Chromosome
129
What is the term for segments of DNA that code for a particular protein?
Genes
130
What is the point where the chromatids are joined?
Centromere
131
What are the identical parts of a chromosome called?
Chromatids
132
What is the material composed of DNA and proteins that makes up the chromatid?
Chromatin
133
What kinds of cells does mitosis produce?
Mitosis produces genetically identical diploid somatic (body) cells.
134
How many chromosomes do human haploid cells have?
Human haploid cells have 23 chromosomes.
135
What kinds of cells does meiosis produce?
Meiosis produces genetically unique haploid gametes (sperm and egg cells).
136
How many cells are produced when one cell goes through meiosis?
Four haploid cells are produced from one diploid cell.
137
How many times are chromosomes replicated during meiosis?
Once, during Interphase (S phase) before meiosis begins.
138
How do cells in meiosis get to be different?
i. Crossing over during Prophase I ii. Independent assortment during Metaphase I iii. Random fertilization when gametes combine
139
If an organism’s somatic cells have 36 chromosomes, how many chromosomes do their gametes have?
Gametes will have 18 chromosomes (half of the somatic cell count).
140
