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Biology > Topic 2 Cells - Course Overview > Flashcards

Topic 2 Cells - Course Overview Flashcards

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1
Q

What is the nucleus? What components make up the nucleus and what do they do?

A

The nucleus contains the genetic material of the cell and controls the cells activities.
The nucleus contains :
Nuclear envelope: double membrane that surrounds the nucleus the outer membrane is continuous onto the endoplasmic reticulum it controls the entry of material and contains the reactions taking place within the nucleus.
Nuclear pores: allow the passage of large molecules such as Menger RNA out of the nucleus.
Nucleoplasm: granular jelly like material that makes up the bulk of the nucleus.
Chromosomes: consist of protein bound linear DNA
Nucleolus: small spherical region that manufactures ribosomal RNA.

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2
Q

What is the function of the mitochondrion and what makes up the mitochondria?

A

The mitochondria are the site of aerobic respiration they are responsible for the production of ATP.
They contain:
A double membrane: this controls the entry and exit of material the inner of the two membranes is folded to form extensions known as cristae.
Cristae: extensions of the inner membrane which provide a large surface area for the attachment of enzymes and other proteins involved in respiration.
Matrix: contains proteins, lipids, ribosomes and DNA.

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3
Q

What is the chloroplast and what parts does it contain?

A

The chloroplast is for carrying out photosynthesis.
They contain:
Chloroplast envelope: a double plasma membrane it is selective and what it allows to enter and leave the chloroplast.
Grana: stacks of up to 100 disc-like structure called thylakoids. Within the thylakoids is the photosynthetic pigment called chlorophyll. The grana are where the first stage of photosynthesis happens.
Stroma: fluid filled matrix where the second stage of photosynthesis takes place

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4
Q

What are three ways in which the chloroplasts are adapted to their function?

A

The granal membranes provide a large surface area for the attachment of chlorophyll, electron carriers and enzymes.

The fluid of the stroma possesses all the enzymes needed to make sugars in the second stage of photosynthesis.

Chloroplasts contain both DNA and ribosomes so they can quickly and easily manufacture some of the proteins needed for photosynthesis.

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5
Q

What is the function of the endoplasmic reticulum and what are the components that make it up?

A

Made of sheets like membranes it is continuous without a nuclear membrane
It consists of:
Rough endoplasmic reticulum: it has ribosomes present on the outer surface and it provides a large surface area for the synthesis of proteins and glycoproteins and it provides a pathway for the transport of materials, especially proteins.

Smooth endoplasmic reticulum: lacks ribosomes on its surface and is often more tubular in appearance it synthesises stores and transport lipids and carbohydrates.

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6
Q

What is the structure and function of the Golgi apparatus?

A

It consists of a stack of membranes that make up flattened sacks/cristernae. With small vehicles, the functions of the Goggi is to: add carbohydrates to proteins to form glycoproteins.
Produce secretary enzymes such as those secreted by the pancreas
Secrete carbohydrates
Transport modify and store lipids
Form lysosomes

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7
Q

What are the functions of the lysosomes?

A

Hydrolysis material ingested by phagocytic cells
Release enzymes to the outside of the cell (excytosis) in order to destroy material around the cell.
Digest worn out organelles
Completely breakdown cells after they have died

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8
Q

What is the function of a ribosome?

A

A ribosome is a small cytoplasm granule found in all cells.
80s I found in new chaotic cells
70s are found in prokaryotic cells
They are the site of protein synthesis.

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9
Q

What are the features and functions of the cell wall?

A

They consist of a number of polysaccharide such as cellulose.
There is a thin layer called the middle lamella which marks the boundary between adjacent cell walls and cement adjacent cells together
The functions of the cell wall are:
To provide mechanical strength in order to prevent the cell bursting under the pressure created by the osmotic entry of water.
To give mechanical strength to the plant as a whole.
To allow water to pass along it and so contribute the movement of water through the plant.

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10
Q

What is a vacuole and what are its functions?

A

A fluid filled sack bounded by a single membrane there within mature plant cells.
The functions of the vacuole are:
Support herbaceous plants by making cells turgid
The sugars and amino acids act as a temporary food store
The pigments may colour petals and attract pollinating insects

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11
Q

What is meant by turgid?

A

A cell that has been filled to the capacity with water by osmosis.

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12
Q

How can you relate cell ultra structure to its function?

A

Each organelle has its own function. It is possible to deduce with reasonable accuracy the role of the cell by looking at the number and size of the organelles for example as mitochondria produce ATP. It follows that cells with many mitochondria are going to need a high rate of energy and therefore a high rate of metabolism.

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13
Q

What is meant by cell specialisation?

A

Each cell has to perform a basic function however no cell can provide the best conditions for all functions therefore the cells are specialised in different ways to perform a particular role.

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14
Q

What is an example of cell specialisation?

A

The first group of cells in an embryo or initially identical as the mature each cell takes on its own characteristics.

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15
Q

How does a cell specialise if all the cells have the same genes?

A

Every cell contains the genes needed for it to develop into any one of the many different cells in an organism, but only some of these jeans are expressed.

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16
Q

What is a tissue?

A

A collection of cells that perform the same specific function.

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17
Q

What are two examples of a tissue?

A

Epithelial tissues - found in animals and consist of sheets of cells they line the surfaces of organs and have a highly protective function.
Xylem - these are curtain plants and are made up of a number of similar cells. They used to transport water and mineral irons throughout the plant and to give mechanicals support.

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18
Q

What is an organ?

A

An organ is a combination of tissues that are coordinated to perform a variety of functions, although they often have one predominant major function.

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19
Q

What is an example and plant example of an organ?

A

The stomach and a leaf.

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20
Q

What is an organ system?

A

Organs work together as a single unit.

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21
Q

What is an organ system?

A

Organs work together as a single unit.

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22
Q

What are three examples of organ systems?

A

The digestive system – digest and processes food.
The respiratory system – used for breathing and gas exchange
The circulatory system – pumps and circulate blood.

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23
Q

There are two main types of cells. What are they?

A

Eukaryotic cells – larger and have a nucleus bounded by nuclear membranes.
Prokaryotic cells – smaller and have known nucleus or nuclear envelope.

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24
Q

What is the structure of a bacterial cell?

A

Cell wall
Capsule
Cell surface membrane
Circular DNA
Plasmid

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25
Q

What is the function of the cell wall in a prokaryotic cell?

A

Physical barrier that excludes certain substances and protects against mechanical damage and osmotic lysis.

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26
Q

What is the function of the capsule in a prokaryotic cell?

A

Protect bacteria from other cells and helps groups of bacteria to stick together for further protection.

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27
Q

What does a cell surface membrane do for a prokaryotic cell?

A

Acts as a differentially permeable layer which controls the entry and exit of chemicals.

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28
Q

What is the function of circular DNA in a prokaryotic cell?

A

Possesses the genetic information for the replication of bacterial cells.

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29
Q

What is the function of plasmids in prokaryotic cells?

A

Possesses jeans that may aid the survival of bacteria in adverse conditions.

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30
Q

What are the seven differences between prokaryotic and eukaryotic cells?

A
  1. Prokaryotic cells have no true nucleus whereas eukaryotic cells have a distinct nucleus with a nuclear envelope.
  2. prokaryotic cells DNA is not associated with protein whereas in eukaryotic cells DNA is associated with proteins called histones.
  3. Prokaryotic cell cells have no membrane bounded organelles whereas eukaryotic cells do have membrane bounded organelles.
  4. Prokaryotic cells have smaller ribosomes. 70s and 80s
  5. Prokaryotic cell wall is made up of murein whereas chaotic cell wall is made up of cellulose.
  6. Some DNA in prokaryotic cells maybe in the form of circular strands called plasma whereas in eukaryotic cells there are no plasma and DNA is linear.
  7. Prokaryotic cells may have a capsule whereas eukaryotic cells won’t.
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31
Q

What is a virus?

A

Viruses are acellular nonliving particles smarter than bacteria they contain nucleic acids such as DNA and RNA as genetic material they can only multiply inside living host cells.

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32
Q

What is the structure of the human immunodeficiency virus?

A

Genetic material
Attachment proteins
Capsid
Lipid envelope
Matrix
Reverse transcriptase

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33
Q

What is mitosis?

A

Mitosis is a type of cell division which produces two identical daughter cells that have the same number of chromosomes as the parent cell and each other.

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34
Q

What is meiosis?

A

A type of cell division which produces for unique daughter cells each with half the number of chromosomes of the parent cell.

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35
Q

What is the structure of a chromosome?

A

Chromatid and centromere.

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36
Q

What happens during interphase of mitosis?

A

This is a long period of cell division. It is the replication of DNA. The two copies of DNA replication remain joined at a place called the centromere.

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37
Q

What happens during prophase?

A

The chromosomes first become visible as long threads which later shorten and become thicker. The centrioles move to the opposite polls of the cell from this spindle fibres develop. The nuclear envelope breaks down and the nucleus disappears leaving the chromosome three in the side of plasma of the cell. The chromosomes are drawn to the equator of the cell.

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38
Q

What happens during the metaphase of mitosis?

A

Each chromatids are joined by the centromere and they are identical copy’s of DNA from the parent cell, the chromatids arrange the themselves along the equator.

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39
Q

What happens in anaphase of mitosis?

A

Centromeres divide into two and spindle fibres pull chromatids apart. Chromatid move to opposite poles of the cell.

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40
Q

What happens during telophase and cytokinesis?

A
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41
Q

What is cell division called in a prokaryotic cell?

A

Binary fission

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42
Q

What is the process of binary fission?

A

The circular DNA molecule replicates and both copies attach to the cell membrane.
The plasmids also replicate.
The cell membrane begins to grown between the two DNA molecules and begins to pinch inward, diving. The cytoplasm into two.
A new cell wall forms diving the original cell into two daughter cells.

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43
Q

How do viruses replicate?

A

They are non-living so cannot undergo cell division. Instead they replicate by catching their host cel with the attachment proteins on their surface. They then inject their nuclei’s acid into the host cell.

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44
Q

How do viruses replicate?

A

They are non-living so cannot undergo cell division. Instead they replicate by catching their host cel with the attachment proteins on their surface. They then inject their nuclei’s acid into the host cell.

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45
Q

What is the cell cycle?

A

When the cells do not have the ability to divide so they undergo a regular cycle of division separated by periods of cell growth.

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46
Q

What are the three stages of the cell cycle and explain them?

A
  1. Interphase -which occupies most of the cell cycle and is sometimes known as the resting phase because no division takes place.
  2. Nuclear division - when the nucleus divides either into two or four.
  3. division of the Coplas – the process by which the cytoplasm divides to produce two new cells
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47
Q

What is cancer?

A

Cancer is a group of diseases caused by an uncontrolled growth disorder of cells. It is the result of damage to the genes that regulate mitosis and the cell cycle.

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48
Q

What is a tumour?

A

A group of abnormal cells that constantly expands in size. A tumour becomes cancerous if it changes from benign to malignant.

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49
Q

What is the difference between benign and malignant tumours?

A

Benign tumours grow slowly and I’m more compact less likely to be life-threatening.
Malignant tumours grow rapidly and are less compact and more likely to be life-threatening.

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50
Q

What does the treatment of cancer often involve?

A

Killing dividing cells by blocking a part of the cell cycle.

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51
Q

How do drugs used to treat cancer distrupt the cell cycle?

A

-Preventing DNA from replicating.
-Inhibiting the metaphase stages of mitosis by interfering with spindle information.

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52
Q

What is the problem with drugs to treat cancer?

A

They can disrupt the normal bodily cells. Some cells are more susceptible to damage than others.

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53
Q

Why is the phospholipids/phospholipid bilayer an important component of the cell surface membrane?

A

-The hydrophilic heads of both phospholipid layers point to the outside of the cell surface membrane attracted by water on both sides.
-The hydrophobic tales of both phospholipid layers point into the centre of the membrane repelled by the water on both sides.

54
Q

What are the functions of the phospholipids in the membrane?

A
  • Allow lipid soluble substances to enter and lead the cell.
    – Prevent water soluble substances entering and leaving the cell.
    – Make the membrane flexible and self-sealing.
55
Q

Proteins are interspersed throughout the cell surface membrane which two ways are proteins embedded into the phospholipid bilayer?

A

-Some proteins occur in the surface of the bilayer and never extend completely across it. They give mechanical support and act as cell receptors.
-This spanned the phospholipid bilayer some accord protein channels and the others are called carrier proteins.

56
Q

What is a protein channel?

A

Protein channels form water filled tubes to allow water soluble ions to diffuse across the membrane.

57
Q

What is a carrier protein?

A

Carrier proteins bind to ions or molecules like glucose and amino acids then they change shape in order to move these molecules across the membrane.

58
Q

What are the functions of proteins in the phospholipid bilayer?

A
  • Provide structural support
    -act as channels transporting water soluble substances across the membrane
    – Allow active transport across the membrane through carrier proteins
    -form Cell surface receptors for identifying cells
    – Help cells adhere together
    – Act as receptors for example hormones.
59
Q

Where are cholesterol molecules found?

A

In the phospholipid bilayer

60
Q

What are the functions of cholesterol in the cell surface membrane?

A

– Reduce lateral movement of other molecules including phospholipids.
– Make the membranes less fluid at high temperatures.
– Prevent leakage of water and dissolved irons from the cell.

61
Q

J

A
62
Q

What are the functions of the glycolipids in the cell surface membrane?

A

– Act as recognition sites
– Help maintain the stability of the membrane
– Help cells to attach to one another and so form tissues

63
Q

What is the functions of glycoproteins?

A

– Act as recognition sites
– Help cells to attach to one another and so form tissues
– Allows cells to recognise one another

64
Q

Why do many molecules not freely diffuse across the cell surface membrane?

A

– Not soluble in lipids and therefore cannot pass through the phospholipid bilayer.
– Two large pass through the channels in the membrane.
– of the same charge as the charge on the protein channels so they are repelled.
– Electrically charged (polar) and therefore have difficulty passing through the non-polar hydrophobic tales.

65
Q

What is the fluid mosaic model of the cell?

A

The way in which all the various molecules are combined into the structure of the cell surface membrane.

66
Q

Why is the fluid mosaic model known as this?

A

– Fluid: because the individual phospholipid molecules can move relative to one another this gives the membrane a flexible structure that is constantly changing shape.
– Mosaic: because the proteins that are embedded in the phospholipid bilayer very in shape size and pattern in the same way as the stones or tiles of a mosaic.

67
Q

What is simple diffusion?

A

The net movement of molecules or ions from a region where they are more highly concentrated to one where their concentration is lower until evenly distributed.

It is a passive process and does not use an external source.

68
Q

What is facilitated diffusion?

A

Like diffusion occurs down a concentration gradient but it differs in that it occurs as specific point on the plasma membrane where there are special protein .

When the movement of molecules is made easier by trans membrane channels and carriers that spam the membrane.

It is a passive process

69
Q

What do protein channels do in terms of facilitated diffusion?

A

These proteins for water filled hydrophilic channels across the membrane. They allow specific water soluble ions to past three. They only open in the presence of a specific ion. The ion bind to the protein causing it to change shape.

70
Q

What do carrier proteins do in terms of facilitated diffusion?

A

Carry a protein span the plasma memory when a specific molecule is present. It binds with the protein. This causes it to change shape in such a way that the molecule is released to the inside of the membrane.

71
Q

What is the definition of osmosis?

A

The passage of water from a region where it has a higher water potential to region where it has a lower water potential through a selectively permeable membrane.

72
Q

What is a solute?

A

Any substance that is dissolved in a solvent. A solvent and a solute together form a solution.

73
Q

What is water potential measured in?

A

KiloPascals

74
Q

What is water potential?

A

The pressure created by water molecules.

75
Q

What is active transport?

A

The movement of molecules or ions into or out of a cell from a region of lower concentration to region of higher concentration using ATP and carrier proteins

76
Q

What is ATP used for in the process of active transport?

A

– Directly move molecules
– Individually move molecules using a concentration gradient.

77
Q

Why does active transport differ from passive transport?

A

– Metabolic energy from the form of ATP is needed.
– Substances are moved against the concentration gradient.
– Carrier protein molecules which act as pumps are involved.
– The process is very selective with substances being transported.

78
Q

Transport and absorption of glucose and the ileum

A
79
Q

What is a pathogen?

A

A microorganism that causes disease.

80
Q

What is immunity?

A

The ability of organisms to resist infection by protecting against disease causing microorganisms or their toxins that invade their bodies.

81
Q

What are two examples of general and immediate defence mechanisms against against pathogens?

A

Physical – the skin is a barrier to protect against pathogens
Chemical – hydrochloric acid in the stomach kills pathogens

82
Q

What are the two defence mechanisms that are less rapid but long lasting and involve a lymphocyte?

A
  1. Cell mediated responses involving T lymphocytes.
  2. Responses involving B lymphocytes.
83
Q

What are the two defence mechanisms that are less rapid but long lasting and involve a lymphocyte?

A
  1. Cell mediated responses involving T lymphocytes.
  2. Responses involving B lymphocytes.
84
Q

To prevent the body from invasion of foreign material what must the lymphocytes be able to do?

A

Distinguish between the bodies, own cells (self) and molecules from those that are foreign (non-self).

85
Q

What would happen if the lymphocytes couldn’t distinguish between it own cells and foreign pathogens?

A

It would destroy the organisms, own tissue.

86
Q

How can lipocytes distinguish between self and non-self cells?

A

Each cell has specific proteins on its surface with highly specific tory structures the structures are unique and this makes them distinguished.

87
Q

What four things do the antigens on the surfaces of cells help the immune system to identify?

A
  1. Pathogens for example HIV.
  2. Non-self material such as cells from other organisms of the same species.
  3. Toxins including those produced by certain pathogens like the bacteria that causes cholera.
  4. Abnormal body cells such as cancer cells.
88
Q

What can be the practical problem with the body attacking non-self material?

A

When individuals have an organ or tissue transplant the immune system recognise the cells as non-self therefore it will attempt to destroy the transplant.

89
Q

How can we minimise the effect of tissue rejection?

A

Tissues for transplant are normally matched as closely as possible to that of the recipient. The matches often come from relatives that are genetically close in addition the same blood type or immuno suppressant drugs are often administer to reduce immune response reaction.

90
Q

What is meant by a non-specific response? What is an example of a non-specific response?

A

A response that is immediate and the same for all pathogens.
An example is phagocytosis or a physical barrier.

91
Q

What is meant by a specific response? What is an example of a specific response?

A

A response that is slower and specific to each pathogen.
An example would be humorous response and cell mediated response.

92
Q

What are the two types of white blood cell?

A

Phagocytes and lymphocytes

93
Q

What is the difference between phagocytes and lymphocytes?

A

Phagocytes ingest and destroy the pathogen by a process called phagocytosis before it can cause harm.

Lymphocytes are involved in immune responses.

94
Q

What is the summarised process of phagocytosis?

A

– Pathogens or dead damaged and abnormal cells act as attractants causing phagocytes to move towards the pathogen.
– They have several receptors on their cell surface membrane that recognise an attach to chemicals on the surface of the pathogen.
– They engulf the pathogen to form a vehicle known as a phagosome.
-Lysosomes move towards the vehicle and fuse with it.
– The enzyme lysozyme is released and hydrolyses the bacteria’s cell walls.
– The soluble products from the breakdown of the pathogens are absorbed into the cytoplasm of the phagocyte.

95
Q

What is an antigen?

A

A protein on the cell surface membrane that is recognised by the immune system as a non-self.

96
Q

What is the non-specific response for fighting infection?

A

Phagocytosis it happens whatever the infection.

97
Q

What is a specific immune response?

A

Slower at first but they provide long-term immunity. There are two responses, cell mediated immunity and the humeral immunity.

98
Q

Where are lymphocytes produced?

A

In the bone marrow

99
Q

What is a B lymphocyte?

A

They mature in the bone marrow and our associated with humeral immunity.

100
Q

What is humoral immunity?(simple)

A

Immunity involving antibodies that are present in body fluids or “ humour” such as blood plasma.

101
Q

What is humoral immunity?

A

Immunity involving antibodies that are present in body fluids or “ humour” such as blood plasma.

102
Q

What are T lymphocytes?(simple)

A

They mature in the thymus gland and they are associated with cell mediated immunity.

103
Q

What is cell mediated immunity?(simple)

A

Immunity involving body cells

104
Q

How can T lymphocytes distinguish invader cells from normal cells?

A

-Going Phagocytes that have hydrolysed the pathogen present the antigens on their own cell surface membrane. (Antigen presenting).
-Body cells that have been invaded by a virus present the viral antigens on their cell surface membrane.
– Cells from different individuals of the same species have different antigens on their cells.
– Cancer cells are different from normal body cells and present antigens on their surface.

105
Q

What is an antigen presenting cell?

A

A cell that will display foreign antigens on their surface.

106
Q

Why are antigen presenting cells necessary?

A

T lymphocytes will only respond to antigens that are presented on the body cell rather than antigens within the body fluids. This is the cell mediated response.

107
Q

What is the role of the receptors on T lymphocytes?

A

The receptors on each lymphocyte respond to a single antigen. There is a large number of T lymphocytes each one corresponding to a different antigen.

108
Q

Explain the process of cell mediated immunity in five steps

A
  1. Pathogens invade the body cells or are taken in by phagocytes.
  2. The phagocyte places antigens from the pathogen on its cell surface membrane.
  3. Receptors on a specific helper T cell fit onto these pathogens.
  4. This attachment activates the T cell to divide rapidly by mitosis and form a clone of genetically identical cells
  5. The cloned cells: develop into memory cells enabling a secondary response for future infections, stimulate Faygo sites to engulf pathogens by phagocytosis, stimulate B cells to divide and secrete their antibody and activate cytotoxic T cells.
109
Q

How do cytotoxic T cells kill infected cells?

A

They kill abnormal body cells that have been affected by pathogens by producing a protein called perforin that makes holes in the cell surface membrane. These holes mean the cell membrane becomes freely permeable to all substances as a result the cell dies.

110
Q

What is an antibody?

A

Found in the blood that is produced by plasma cells which binds to antigens as part of the immune response.

111
Q

What is endocytosis?

A

The process by which cell take substances from outside of the cell bone and engulfing them in a vesicle.

112
Q

What is a monoclonal antibody?

A

Identical antibodies that have been produced by an immune cell that has been cloned from a parent cell.

113
Q

Which two types of cells do monoclonal antibodies develop into?

A

Plasma cells and memory cells.

114
Q

What do plasma cells do in terms of humeral immunity?

A

They secrete antibodies usually in the blood plasma they make around 2000 antibodies every second they lead to the destruction of the antigen. They are responsible for the immediate defence known as the primary immune response.

115
Q

What do memory cells do in terms of humoral immunity?

A

They are responsible for the secondary immune response. They live considerably longer than plasma cells. They do not produce antibodies directly when they encounter the same antigen at a later date they divide rapidly and developed into plasma cells and more memory cells the plasma cells fight the infection and in this way this provides long-term immunity.

116
Q

Give a summary of the process of B cells in humoral immunity. (7 stages)

A
  1. The surface antigens on an invading pathogen are taken up by a B cell.
  2. The B cell processes the antigen and presents them on its surface.
  3. Helper T cells attached to the processed antigens on the B cell thereby activating the B cell.
  4. The B cell is now activated to divide by mitosis to give a clone of plasma cells.
  5. The cloned plasma cells produced and secrete the specific antibody that fits the antigen on the pathogen surface.
  6. The antibody attaches to antigens on the pathogen and destroys them.
  7. Some B cells developed into memory cells to create a secondary response in the future.
117
Q

Tell me about antibody binding sites.

A

Antibodies are synthesised by B cells they have two identical binding sites specific to an antigen to form the antibody antigen complex.

118
Q

What is the structure of an antibody?

A

They are made up of four polypeptide chains the chains of one pair along and are called heavy chains why the short pair are known as light chains? The binding on each antibody is different and there for known as a variable region each binding site consists of a sequence of amino acids that form a 3-D shape that binds directly to the specific antigen the rest of the antibody has known as the constant region that binds the receptors on the B cell

119
Q

How do you antibodies lead to the destruction of an antigen?

A

-they cause a agglutination of the bacterial cells in this way clumps are formed making it easier for the phagocytes to locate them.
-They then serve as markers that stimulate phagocytes to end the bacterial cells to which they are attached.

120
Q

How can monoclonal antibodies be used for in medical practices?

A

They can be used to target specific substances and specific cells such as cancer cells.

121
Q

The best way to treat cancer using monoclonal antibodies is to use direct monoclonal antibody therapy. What is this?

A

– Monoclonal antibodies are produced that are specific antigens on cancer cells.
– These antibodies are given to a patient and attach themselves to the receptors on their cancer cells
– They attached the surface of their cancer cells and block the chemical signals that stimulate their uncontrolled growth.

122
Q

What does indirect monoclonal antibody therapy involve?

A

Attaching a radioactive or cytotoxic drug to the antibody.

123
Q

Other than treating medical illnesses, what other way can monoclonal antibodies be used for in medicine?

A

Medical diagnosis

124
Q

How can monoclonal antibodies be used in pregnancy testing?

A

– The placenta produces a hormone called human chorionic gonadotropin (hCG) found in the mother’s urine.
– monoclonal antibodies present on the test strip are linked to coloured particles.
-If hCG is present it binds to these antibodies.
– the hCG-antibody-colour complex moves along the strip until it is trapped by a different type of antibody creating a coloured line.

125
Q

What are the ethical issues from the development of monoclonal antibodies?

A

– The production of monoclonal antibodies involves the use of mice. They used to produce both antibodies and cells. This involves deliberately producing cancer.
– There have been some deaths associated with the treatment of multiple sclerosis.
– A testing of six healthy volunteers of monoclonal antibodies caused multiple organ failure within a few minutes.

126
Q

What is passive immunity?

A

Introduction of antibodies into individuals from an outside source there is no direct contact with the pathogen or its antigen to induce necessary immunity.

127
Q

What is active immunity?

A

Stimulating the production of antibodies by the individuals own immune system direct contact with the pathogen or its antigens is necessary.

128
Q

What is natural active immunity?

A

It results from an individual becoming infected with a disease under normal circumstances.

129
Q

What is natural active immunity?

A

It results from an individual becoming infected with a disease under normal circumstances.

130
Q

What is artificial active immunity?

A

Forms the basis of vaccination it involves inducing an immune response without them suffering the symptoms of the disease.

131
Q

What is a vaccine?

A

The introduction of the appropriate disease antigens into the body to induce an immune response.

Biology (8 decks)

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