A2.2 Cell Structure Flashcards
Not including atypical cells
1
Q
What type of genetic material do typical prokaryotic and eukaryotic cells contain?
A
DNA
2
Q
What is the main component of the cytoplasm in typical prokaryotic and eukaryotic cells?
A
Water
3
Q
What is the structure that encapsulates the contents of a cell?
A
Plasma membrane
4
Q
The plasma membrane of cells is primarily made of _______.
A
Lipids
5
Q
Prokaryotic and eukaryotic cells contain which four common structures?
A
- DNA as genetic material
- Cytoplasm composed mainly of water
- Plasma membrane made of lipids
- Ribosomes
6
Q
What type of organisms are prokaryotes?
A
Unicellular organisms
7
Q
Do prokaryotes contain membrane-bound organelles?
A
No
8
Q
-
A
-
9
Q
What is the size of prokaryotic ribosomes?
A
70S
10
Q
What is the size of eukaryotic ribosomes?
A
80S
11
Q
Where are all prokaryotic ribosomes located?
A
Free in the cytoplasm
12
Q
What is the typical diameter range of prokaryotic cells?
A
0.1 to 5.0 μm
13
Q
What is the typical diameter range of eukaryotic cells?
A
10 to 100 μm
14
Q
True or False: Prokaryotic cells are larger than eukaryotic cells.
A
False
15
Q
Fill in the blank: Prokaryotic ribosomes are smaller than eukaryotic ribosomes, measuring _______.
A
70S
16
Q
What does the ‘S’ in 70S and 80S ribosomes refer to?
A
Svedberg unit
17
Q
What is the function of the cell wall?
A
Protects against toxins, resists high osmotic pressures, maintains cell shape
The cell wall is located outside the cell membrane.
18
Q
What role does the plasma membrane play?
A
Separates the cell’s interior from the external environment and controls substance entry and exit.
19
Q
What is the cytoplasm?
A
A water-based jelly-like fluid that fills the cell and is the site of metabolic reactions.
20
Q
What is naked DNA?
A
DNA that is not associated with histone proteins and is mostly found in the nucleoid region.
21
Q
What is the purpose of ribosomes in cells?
A
Site where translation (protein synthesis) occurs
22
Q
What are plasmids?
A
Small, circular pieces of DNA that can be transferred between prokaryotic cells.
23
Q
Fill in the blank: The _______ is a region where naked DNA is mostly found in prokaryotic cells.
A
nucleoid
24
Q
True or False: Prokaryotic ribosomes are larger and of higher mass than eukaryotic ribosomes.
A
False
25
What is horizontal gene transfer in prokaryotes?
Transfer of plasmids from one prokaryotic cell to another.
26
What is a key difference between eukaryotic and prokaryotic cells?
Eukaryotic cells contain a nucleus and membrane-bound organelles
27
Are eukaryotic cells generally larger or smaller than prokaryotic cells?
Larger
28
What type of cellular organization do all prokaryotes exhibit?
Unicellular
29
Can eukaryotes be unicellular or multicellular?
Both unicellular and multicellular
30
Fill in the blank: Eukaryotic cells are more _______ than prokaryotic cells.
Complex
31
What defines eukaryotic cells in terms of organelles?
Contain membrane-bound cytoplasmic organelles
32
True or False: All eukaryotic organisms are multicellular.
False
33
What is compartmentalisation in eukaryotic cells?
The presence of membrane-bound cytoplasmic organelles like mitochondria and chloroplasts.
34
What does compartmentalisation allow in eukaryotic cells?
It allows for separate conditions within organelles compared to the cytoplasm of the cell.
35
What is one advantage of compartmentalisation?
The ability to create higher concentrations of certain substances within organelles.
36
How does compartmentalisation help with toxins?
It allows for the separation of toxins and potentially damaging substances from the rest of the cell.
37
What condition can be controlled inside organelles due to compartmentalisation?
pH.
38
Fill in the blank: The ability to control conditions inside organelles helps maintain the optimal conditions for _______.
enzymes.
39
What is the function of the plasma membrane?
Separates the cell’s interior from its external environment and controls what can enter and exit the cell.
40
What is cytoplasm?
A water-based jelly-like fluid that fills the cell, suspends ions, organic molecules, organelles and ribosomes, and is the site of metabolic reactions.
41
What do mitochondria do?
Convert glucose into ATP in the process of respiration.
42
What type of ribosomes are found in eukaryotic cells?
80S ribosomes.
43
Where does translation (protein synthesis) occur in eukaryotic cells?
In the 80S ribosomes.
44
What is contained within the nucleus?
DNA associated with histone proteins organized into chromosomes.
45
What is the role of the nucleolus?
Involved in the production of ribosomes.
46
What type of membrane does the nucleus have?
A double membrane with pores.
47
What substances can pass through the nuclear pores?
Glucose, RNA and ions.
48
What does the smooth endoplasmic reticulum produce?
Lipids, including steroids.
49
What is the function of the rough endoplasmic reticulum?
Produces proteins that are usually destined for use outside the cell.
50
What does the Golgi apparatus do?
Processes and packages proteins, which are then released in Golgi vesicles.
51
What is a vesicle?
A small sac that transports and releases substances produced within the cell.
52
What is the function of a vacuole?
Helps to maintain the osmotic balance of the cell and may store substances.
53
What is the cytoskeleton made of?
A system of protein fibres called microtubules and microfilaments.
54
What is the role of the cytoskeleton?
Helps to hold organelles in place and maintain the structure and shape of the cell.
55
Fill in the blank: The plasma membrane controls what can enter and exit the _______.
[cell]
56
True or False: Mitochondria are responsible for protein synthesis.
False
57
Fill in the blank: The _______ is involved in the production of ribosomes.
[nucleolus]
58
What are centrioles?
Two cylindrical organelles that help to establish and organise microtubules
## Footnote
Centrioles play an important role in cell division.
59
What is the function of centrioles in animal cells?
To establish and organise microtubules, aiding in cell division
## Footnote
Centrioles are crucial for the proper separation of chromosomes during cell division.
60
What are lysosomes?
Membrane-bound bags of hydrolytic enzymes that break down biological molecules and old cellular organelles
## Footnote
Lysosomes are essential for cellular waste disposal and recycling.
61
In which type of cells are lysosomes found in high concentrations?
Phagocytic white blood cells
## Footnote
These cells use lysosomes to fuse with and destroy ingested pathogens.
62
What is the role of lysosomes in phagocytic white blood cells?
To fuse with and destroy ingested pathogens
## Footnote
This process is vital for the immune response.
63
Fill in the blank: Centrioles help to establish and organise _______.
microtubules
64
True or False: Lysosomes are involved in cell division.
False
## Footnote
Lysosomes primarily function in breaking down waste and cellular debris.
65
What are cilia?
Hair-like structures made of microtubules
66
What is the primary function of cilia in animal cells?
Movement of substances past the cell
67
Where can many cilia be found in the body?
On the epithelial cells of the bronchi
68
What do cilia on bronchial epithelial cells do?
Beat in unison to move microbes and debris up and out of the respiratory tract
69
True or False: Cilia are involved in the movement of substances in the respiratory tract.
True
70
Fill in the blank: Cilia are important for the _______ of substances past the cell.
movement
71
What is the main component of the plant cell wall?
Cellulose
## Footnote
Cellulose is a polysaccharide that provides structural support to the cell.
72
What function does the cell wall serve in plant cells?
Protects the cell and resists osmotic pressure
## Footnote
It helps maintain the shape of the cell.
73
What are chloroplasts?
Double-membrane-bound organelles that convert light energy into chemical energy
## Footnote
This process occurs during photosynthesis.
74
What is a plastid?
A small organelle responsible for manufacturing and storing chemical energy
## Footnote
Chloroplasts are one type of plastid.
75
What gives chloroplasts their green color?
Chlorophyll
## Footnote
Chlorophyll is the pigment found within chloroplasts.
76
How does the size of vacuoles in plant cells compare to those in animal cells?
Vacuoles in plant cells are much larger
## Footnote
They play an important role in regulating the osmotic potential of the cell.
77
Fill in the blank: The vacuole in plant cells is important for regulating the _______.
osmotic potential
## Footnote
This function is crucial for maintaining cell turgor and overall plant health.
78
What is the composition of the cell wall in fungal cells?
The cell wall is made of a polysaccharide called chitin.
## Footnote
Chitin is a structural polysaccharide found in many organisms, including fungi and arthropods.
79
What is the function of large vacuoles in fungal cells?
Large vacuoles break down molecules and act as a storage site for small molecules such as ions.
## Footnote
Vacuoles are essential for maintaining the internal environment of the cell.
80
Do fungal cells contain centrioles?
Centrioles are present in some fungi for producing and organizing the cytoskeleton and playing a key role in cell division, but they are not present in most fungi.
## Footnote
Male gametes of some fungi are an exception where centrioles are found.
81
What are examples of unicellular and multicellular fungi?
Unicellular fungi include Saccharomyces cerevisiae, while multicellular fungi include mushrooms and toadstools.
## Footnote
Saccharomyces cerevisiae is commonly known as baker's yeast.
82
What process is believed to have led to the evolution of eukaryotic cells?
Endosymbiosis
## Footnote
Endosymbiosis is the process where one cell engulfs another and incorporates it into its cellular structure.
83
From what type of ancestor do all eukaryotes evolve?
84
What organelle developed from the engulfment of an aerobic bacterium?
Mitochondria
## Footnote
The aerobic bacterium lost its independent utility and became part of the eukaryotic cell.
85
What organelle likely resulted from the internalization of a photosynthetic cyanobacterium?
Chloroplast
## Footnote
This contributed to the development of chloroplasts in plant cells.
86
What are the two organelles that are believed to have arisen via endosymbiosis?
Mitochondria and chloroplasts
## Footnote
Both organelles share characteristics with bacteria due to their prokaryotic origins.
87
What is one piece of evidence for the endosymbiotic origins of mitochondria and chloroplasts?
Double membrane
## Footnote
Both organelles have a double membrane, with the outer membrane possibly being vesicular in origin.
88
Mitochondria and chloroplasts are susceptible to what type of substances?
Antibiotics
## Footnote
This susceptibility is because antibiotics target prokaryotic features.
89
What type of DNA do mitochondria and chloroplasts possess?
Naked and circular DNA
## Footnote
This is similar to the DNA found in prokaryotes.
90
How do mitochondria and chloroplasts divide?
By a process similar to binary fission
## Footnote
This is the same method of reproduction used by bacteria.
91
What type of ribosomes do mitochondria and chloroplasts have?
70S ribosomes
## Footnote
This is also the type of ribosomes found in prokaryotic cells.
92
What are the functions that multicellular organisms can complete that unicellular organisms cannot?
Emergent properties due to collective actions of individual cells
## Footnote
Emergent properties arise when cells work together, leading to new functions.
93
What are emergent properties?
New functions arising from the collective actions of individual cells
## Footnote
These properties result from cell specialization and the interaction of different cell types.
94
What causes cells in multicellular organisms to become specialized?
Differential expression of genes
## Footnote
This process allows cells to develop unique functions tailored to specific roles.
95
What may coordinate the differing patterns of gene expression in multicellular organisms?
Extracellular signals or changes in the environment
## Footnote
These signals can influence how genes are expressed, leading to specialization.
96
What do cells of the same type form in multicellular organisms?
Tissues
## Footnote
Tissues consist of similar cells working together to perform specific functions.
97
What is formed by the functional grouping of multiple tissues?
Organs
## Footnote
Organs are structures made up of different tissues that work together to perform specific tasks.
98
What do organs interact to form in multicellular organisms?
Organ systems
## Footnote
Organ systems are groups of organs that work together to carry out complex functions.
99
What do organ systems collectively carry out?
Life functions of the complete organism
## Footnote
These functions are essential for the survival and health of the organism.
100
What has evolved repeatedly and offers several distinct survival advantages?
Multicellularity
## Footnote
Multicellularity allows organisms to adapt and thrive in various environments.
101
What allows an organism to exceed size limits imposed by SA:Vol ratio limitations?
Being multicellular
## Footnote
The surface area to volume ratio restricts the size of single-celled organisms.
102
How can multicellular organisms have longer lifespans?
They can survive the death of an individual cell
## Footnote
This resilience contributes to the overall longevity of the organism.
103
What does multicellularity foster within a single organism?
Complexity through differentiation of cell types
## Footnote
Differentiation allows for specialized functions and tissue types.
