Workbook 2 Flashcards
1
Q
What is the function of mitochondria?
A
Required for aerobic respiration; produce ATP for muscle contraction.
2
Q
What is the main site of photosynthesis in plants?
A
Palisade mesophyll cells.
3
Q
Identify the organelle that synthesizes RNA.
A
Nucleolus.
4
Q
What structure is responsible for modifying and packaging proteins?
A
Golgi body.
5
Q
Which organelle contains DNA/chromatin that codes for amino acid sequences in proteins?
A
Nucleus.
6
Q
Fill in the blank: The _______ is a membrane that surrounds the nucleus.
A
Nuclear envelope.
7
Q
What is the primary function of ribosomes?
A
Synthesize proteins.
8
Q
True or False: The cell wall is present in animal cells.
A
False.
9
Q
What is the function of vacuoles in plant cells?
A
Store water, amino acids, and pigments; maintain turgidity.
10
Q
List the structures found in prokaryotic cells.
A
- Ribosomes
- Cell membrane
- DNA (circular genomic)
- Cell wall
- Capsule
- Flagella
- Pili.
11
Q
What do viruses lack compared to prokaryotic cells?
A
Cell structure, metabolism, and membrane-bound organelles.
12
Q
What is the role of the plasmid in prokaryotic cells?
A
Carry additional genetic information.
13
Q
Fill in the blank: A virus is considered _______ because it is not made of cells.
A
Acellular.
14
Q
What microscope uses light to magnify specimens?
A
Light microscope.
15
Q
True or False: The transmission electron microscope (TEM) can be used to view live specimens.
A
False.
16
Q
What are the advantages of using a scanning electron microscope (SEM)?
A
- Produces 3D images
- Provides high magnification and resolution.
17
Q
What is the function of the rough endoplasmic reticulum?
A
Synthesis of proteins.
18
Q
What structure provides strength and support to bacterial cells?
A
Cell wall.
19
Q
Define the term ‘homogenized’ in the context of cell preparation.
A
Breaking down cells to release organelles.
20
Q
What is the purpose of using a buffered solution during cell preparation?
A
Maintain a stable pH.
21
Q
Fill in the blank: The _______ is the part of the nucleus where ribosomal RNA is synthesized.
A
Nucleolus.
22
Q
What structures are found in both plant and animal cells?
A
- Mitochondria
- Ribosomes
- Endoplasmic reticulum
- Nucleus.
23
Q
What is the difference in ribosome size between prokaryotic and eukaryotic cells?
A
Prokaryotic cells have smaller (70S) ribosomes.
24
Q
What is the role of attachment proteins in viruses?
A
Bind to receptors on target cells.
25
What is the magnification formula?
Image size / actual size.
26
Fill in the blank: The _______ is the semi-permeable membrane surrounding the cell.
Cell membrane.
27
What is the function of chloroplasts?
Site of photosynthesis.
28
What is the role of the Golgi apparatus in protein processing?
Modifies, packages, and secretes proteins.
29
What is the difference between the smooth and rough endoplasmic reticulum?
* Smooth ER: Synthesizes lipids
* Rough ER: Synthesizes proteins.
30
What is the formula for calculating actual size from image and magnification?
Image / magnification = actual
## Footnote
This formula helps in determining the actual size of an object based on its magnified image and the magnification factor.
31
How do you convert measured length into micrometers?
Measured length in mm multiplied by 1000
## Footnote
To convert from millimeters to micrometers, multiply by 1000 since 1 mm = 1000 μm.
32
What is the actual size of an object measured as 72 mm with a magnification of 10,400x?
6.9 μm
## Footnote
Calculation: 72,000 μm / 10,400 = 6.9 μm.
33
What organelle is referred to when discussing cell size calculations?
mitochondria
## Footnote
Mitochondria are often used in examples of cellular measurements due to their importance in cellular respiration.
34
What is the actual size of an object measured as 54 mm with a magnification of 30,000x?
1.8 μm
## Footnote
Calculation: 54,000 μm / 30,000 = 1.8 μm.
35
What type of microscope is abbreviated as TEM?
Transmission electron microscope
## Footnote
TEM is used for high-resolution imaging of biological samples.
36
What is the formula to calculate image size from actual size and magnification?
Image / actual = magnification
## Footnote
This formula is used to determine the magnification factor based on the size of the image and the actual size.
37
During which phase do chromosomes condense and become visible?
prophase
## Footnote
Prophase is the first stage of mitosis where chromatin condenses into chromosomes.
38
What occurs during metaphase?
Chromosomes line up on the equator of the cell
## Footnote
Metaphase is characterized by the alignment of chromosomes at the cell's equatorial plane.
39
What happens to sister chromatids during anaphase?
They are pulled to opposite poles of the cell
## Footnote
Anaphase is the stage where sister chromatids separate and move to opposite sides of the cell.
40
What is the role of a buffer in cell preparation?
Prevents damage to enzymes/proteins
## Footnote
Buffers help maintain pH levels, which is crucial for enzyme activity.
41
What does the term 'supernatant' refer to in cell biology?
Liquid above the pellet
## Footnote
The supernatant is the clear liquid that remains after centrifugation of a cell suspension.
42
What phase of the cell cycle is characterized by DNA replication?
S-phase
## Footnote
S-phase is the part of interphase where DNA is replicated in preparation for cell division.
43
What is the mitotic index formula?
Number of cells in mitosis / Total number of cells x 100
## Footnote
The mitotic index is a measure of the proportion of cells undergoing mitosis in a given population.
44
What happens to chromosomes during telophase?
Nuclear membrane reforms
## Footnote
Telophase is characterized by the reformation of the nuclear envelope around the separated chromatids.
45
What is the primary function of carrier proteins in cell membranes?
Facilitated diffusion of large or charged particles
## Footnote
Carrier proteins assist in the transport of substances across the cell membrane without using energy.
46
Fill in the blank: The model of the cell membrane is called the _______.
fluid mosaic model
## Footnote
This model describes the structure of cell membranes as a mosaic of diverse protein molecules embedded in a fluid bilayer of phospholipids.
47
What is the function of glycoproteins in cell membranes?
Act as recognition sites and allow cells to adhere together
## Footnote
Glycoproteins play crucial roles in cell-cell recognition and communication.
48
True or False: Cholesterol provides strength and rigidity to cell membranes.
True
## Footnote
Cholesterol helps maintain membrane fluidity and stability under varying temperature conditions.
49
What is the difference between hydrophilic and hydrophobic regions of phospholipids?
Hydrophilic is water-loving; hydrophobic is water-hating
## Footnote
This property is critical for the formation of the phospholipid bilayer in cell membranes.
50
What are proteins in the membrane described as?
Proteins are distributed throughout/ irregularly within the bilayer (and can move)
## Footnote
This highlights the fluid mosaic model of membrane structure.
51
What two components are needed for the process of diffusion?
Phospholipid AND channel / intrinsic protein
## Footnote
Both components are essential for the movement of substances across the membrane.
52
What types of molecules can pass through the membrane easily?
Small AND nonpolar / uncharged
## Footnote
Examples include oxygen and carbon dioxide.
53
What types of molecules cannot pass through the membrane easily?
Large AND polar
## Footnote
These molecules often require assistance from proteins to cross the membrane.
54
Fill in the blank: Water moves from a high to ______ water potential.
[low]
## Footnote
This describes the direction of water movement during osmosis.
55
True or False: Isotonic refers to a solution with the same water potential as cell cytoplasm.
True
## Footnote
Isotonic solutions do not cause net movement of water into or out of cells.
56
What happens to an animal cell placed in pure water?
Water will move in via osmosis, causing the cell to swell and burst.
## Footnote
This is due to the higher water potential outside the cell.
57
What is facilitated diffusion?
Facilitated diffusion occurs via channel or carrier proteins.
## Footnote
This process is necessary for charged or large polar particles.
58
What is active transport?
Active transport occurs against a concentration gradient via protein carrier using ATP.
## Footnote
This process requires energy to move substances from low to high concentration.
59
What is co-transport?
Co-transport of 2 different substances using a carrier protein.
## Footnote
This mechanism allows for the simultaneous transport of molecules.
60
Fill in the blank: The term ______ refers to the process of water moving across a selectively permeable membrane.
[osmosis]
## Footnote
Osmosis specifically refers to the movement of water molecules.
61
What are the stages of phagocytosis?
1. Pathogen invades and releases chemicals.
2. Phagocyte is attracted to the chemicals.
3. Phagocyte engulfs the pathogen into a vesicle.
4. Lysosomes fuse with the phagosome and digest the pathogen.
5. Antigens are presented on the surface of the phagocyte.
## Footnote
This process is crucial for the immune response.
62
What is the role of helper T cells?
Helper T cells (or TH cells) assist in the immune response.
## Footnote
They stimulate other immune cells, including B cells and phagocytes.
63
What are memory B cells?
Memory B cells are long-lived cells that remember past infections.
## Footnote
They provide immunity by responding more rapidly upon re-exposure to the same pathogen.
64
What is the difference between passive and active immunity?
Passive immunity is acquired through antibodies, while active immunity is developed by exposure to antigens.
## Footnote
Active immunity involves the immune system generating its own response.
65
Fill in the blank: The process of vaccination introduces ______ to the immune system.
[antigens]
## Footnote
Vaccination helps the body build an immune response against specific pathogens.
66
What is an antigen?
A substance that stimulates an immune response
## Footnote
Antigens are typically proteins or polysaccharides found on the surface of pathogens.
67
What is a phagocyte?
A type of cell that engulfs and digests foreign particles or pathogens
## Footnote
Phagocytes include macrophages and neutrophils.
68
What are lysozymes?
Enzymes that break down bacterial cell walls
## Footnote
Lysozymes are found in various body fluids, including tears and saliva.
69
What are Helper T cells?
A type of T cell that aids in activating B cells and other immune cells
## Footnote
Also known as TH cells, they play a crucial role in the immune response.
70
What are Cytotoxic T cells?
T cells that kill infected or cancerous cells
## Footnote
Also referred to as killer T cells.
71
What is the variable region of an antibody?
The part of an antibody that binds to a specific antigen
## Footnote
This region varies between different antibodies, allowing them to recognize different antigens.
72
What is an antigen-antibody complex?
The structure formed when an antibody binds to its specific antigen
## Footnote
This complex is crucial for the immune response.
73
What does agglutination mean in immunology?
The clumping together of pathogens caused by antibodies
## Footnote
This process aids in phagocytosis.
74
What are Memory B cells?
B cells that remain in the body after an infection and provide long-term immunity
## Footnote
They enable a faster response upon re-exposure to the same pathogen.
75
What is vaccination?
The administration of a vaccine to stimulate an immune response
## Footnote
Vaccines often contain weakened or inactive forms of pathogens.
76
True or False: T and B cells are lymphocytes.
True
77
Fill in the blank: The _____ response involves B lymphocytes.
humoral
78
What do Helper T cells do?
Activate B cells and other immune cells
## Footnote
They play a pivotal role in coordinating the immune response.
79
What do plasma cells produce?
Antibodies
80
What ensures a faster secondary response to reinfection?
Memory T and B cells
81
What does the term herd immunity refer to?
When a large portion of a population becomes immune to a disease, reducing its spread
82
What is the role of lysozymes in the immune system?
To digest bacterial cell walls
83
What is the function of reverse transcriptase in HIV?
To transcribe viral RNA into DNA
84
What happens during HIV replication?
The viral RNA is released into the host cell and reverse transcriptase synthesizes viral DNA
## Footnote
The viral DNA integrates into the host's genome.
85
What is a monoclonal antibody?
An antibody produced by a single clone of B cells
## Footnote
Monoclonal antibodies are used in various therapies and diagnostic tests.
86
What is the purpose of washing in ELISA testing?
To remove unbound antibodies and prevent false positives
87
Fill in the blank: Passive immunity does not produce _____ cells.
memory
88
What is the main component of the HIV virus that allows it to infect host cells?
Glycoprotein spikes
89
What does the term 'latent' mean in the context of HIV?
The viral DNA remains inactive within the host cell
90
What is the consequence of HIV destroying T cells?
Impaired immune response leading to opportunistic infections
91
True or False: Antibodies are produced in response to the presence of antigens.
True
92
What is the significance of the variable region in antibodies?
It allows antibodies to bind specifically to their corresponding antigens
93
What is the role of helper T cells in activating B cells?
They bind to antigens presented by antigen-presenting cells
94
Fill in the blank: Antigens have a specific _____ structure that is recognized by antibodies.
tertiary
95
What is the function of antibodies in the immune response?
To neutralize pathogens and mark them for destruction by other immune cells
96
What are the steps involved in HIV replication?
1. Attachment to host cell
2. Fusion with cell membrane
3. Release of viral RNA
4. Reverse transcription to DNA
5. Integration into host DNA
6. Replication of viral components
7. Assembly of new viruses
8. Budding off from the host cell
