What are the main parts of a neuron?
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Dendrite, Cell Body, Axon.
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What are the main parts of a neuron?
Dendrite, Cell Body, Axon.
What is antigenic variation?
The ability of pathogens to change their antigens to evade the immune system.
What occurs during naturally acquired immunity?
A person is exposed to a live pathogen, develops the disease, and becomes immune as a result of the primary immune response.
What leads to T lymphocytes responding to self-antigens?
Failure in regulation of the immune system.
In which direction does a nerve impulse travel in a neuron?
Dendrites -> Cell Body -> Axon.
How can antigenic variation occur?
Through random mutation or programmed changes in protein expression.
What is the result of T lymphocytes attacking the body's own cells?
Autoimmune diseases.
What is an example of naturally acquired immunity?
Catching chickenpox.
What are chemical secretions produced against?
Invading pathogens.
What is the function of dendrites in a neuron?
To receive signals from other neurons.
Why are some pathogens better at evading the immune response?
Because they can change their antigens more effectively than others.
Name two autoimmune diseases mentioned.
Type 1 diabetes and rheumatoid arthritis.
What induces artificially acquired active immunity?
A vaccine, which contains the antigen.
What is a pathogen?
A bacterium, virus, or other organism that can cause disease.
What is the role of the cell body in a neuron?
To process incoming signals and maintain the neuron's health.
What enzyme do tears contain that helps destroy bacteria?
Lysozyme.
What is one consequence of antigenic variation for memory cells?
Memory cells become ineffective against pathogens that change their antigens.
What is the primary purpose of clinical trials?
To find new and improved ways of preventing, diagnosing, treating, and controlling illnesses.
What is the primary response in immunology?
The first response to an antigen that produces antibodies.
What is immunity?
The ability of the body to resist infection by a pathogen or to destroy the organism if it invades.
What is the role of a vaccine in the immune response?
It stimulates a primary response against the antigen without causing symptoms of disease.
What is the function of lysozyme in tears and saliva?
It digests the cell walls of bacteria and destroys them.
How does antigenic variation relate to the influenza virus?
It allows the influenza virus to remain a major public health problem, requiring annual vaccinations.
What is the function of the axon in a neuron?
To transmit nerve impulses away from the cell body.
How are participants involved in clinical trials?
In a controlled and carefully planned way.
What is the first line of defense in non-specific immunity?
Physical and chemical defenses.
Why is the primary response often unable to prevent illness?
It takes time to produce antibodies.
What types of lymphocytes are produced as a result of vaccination?
B Lymphocytes and T Lymphocytes.
What role does mucus play in the immune system?
It is sticky and helps to trap microorganisms.
What is a key reason individuals at risk need to be vaccinated against influenza every year?
Due to the antigenic variation of the influenza virus.
What is required for neurotransmitter molecules to transmit an impulse?
A minimum number must attach to receptors to reach threshold on the postsynaptic membrane.
What are the main questions clinical trials aim to answer?
Does it work? Is it safe? Does it cause side effects? How does it affect quality of life? Does it work better than existing treatments?
How does non-specific defense work?
It works against any type of disease-causing agent.
What is the Herd Immunity Threshold for Diphtheria?
85%.
What do memory cells do after vaccination?
They persist and can initiate a secondary response if exposed to the normal disease-causing antigen later.
How do ciliated cells contribute to respiratory defense?
They sweep mucus and trapped microbes up and away from the lungs.
What do antibodies bind to in order to inactivate pathogens?
Antigens.
How do synapses filter weak stimuli?
By filtering out weak stimuli arising from insufficient secretion of neurotransmitters.
What role do epithelial cells play in physical defense?
They form a physical barrier and offer protection as long as the skin remains intact.
What must vaccines demonstrate before being licensed for use?
They must be shown to be safe and effective when used in humans.
What is peristalsis?
The rate of contraction of smooth muscle in the digestive tract.
What is the transmission method for Measles?
Airborne through saliva droplets.
What is the result of vaccination?
The person acquires artificial immunity.
What is the pH range of stomach acid?
1.5 - 3.5.
What is the process called when the antigen-antibody complex is destroyed?
Phagocytosis.
What is summation in the context of neurotransmission?
A process where a series of weak stimuli combine to trigger enough neurotransmitter to fire an impulse in the postsynaptic neuron.
Where are closely packed epithelial cells found?
In the skin and inner linings of the digestive and respiratory systems.
What happens to peristalsis when the rate of contraction of smooth muscle decreases?
There is a decreased rate of peristalsis.
What are the three main protocols used in vaccine clinical trials?
Randomised, double-blind, and placebo-controlled.
What is the Herd Immunity Threshold range for Measles?
83 - 94%.
What triggers an allergic reaction?
B Lymphocytes responding to harmless antigens like pollen.
What is the effect of stomach acid on microbes?
It destroys many of the microbes that have been swallowed.
What determines the type of alteration to a postsynaptic membrane after neurotransmitter binding?
The type of receptor present, either excitatory or inhibitory.
Where can summation occur?
At converging neural pathways.
What is the primary role of the nervous system?
To analyze sensory information from the body and the external environment.
What occurs when the rate of contraction of smooth muscle increases?
There is an increased rate of peristalsis.
What is the transmission route for Poliomyelitis?
Faecal-oral route.
What substance is secreted during an allergic reaction?
Histamine.
What is the effect of an excitatory signal?
It causes contraction in muscle.
What are endorphins?
Neurotransmitters that stimulate neurons involved in reducing the intensity of pain.
What happens to some of the sensory information analyzed by the nervous system?
It is stored, and decisions are made for appropriate responses and behavior.
What effect does the sympathetic system have on heart rate and breathing rate?
It speeds up heart rate and breathing rate.
What is a phagocyte?
A motile cell that can recognize pathogens.
What are the two main types of cells in the nervous system?
Neurones and glial cells.
What is the function of diverging neural pathways?
Impulses from one neuron travel to several neurons, affecting multiple destinations simultaneously.
What is the purpose of randomisation in a trial?
To put subjects into different groups at random, reducing bias in characteristics like age and gender.
What is the third line of defense in the immune system?
Lymphocytes.
What is the Herd Immunity Threshold for Whooping Cough?
92 - 94%.
What do lymphocytes recognize on the body's own cells?
Self-antigens.
What is the effect of an inhibitory signal on heart muscle?
It reduces the rate and strength of contraction.
What feelings are increased levels of endorphins linked to?
Feelings of pleasure from activities such as eating, sex, and prolonged exercise.
What type of responses does the nervous system initiate?
Motor responses that either initiate muscular contractions or glandular secretions.
What happens to some B and T lymphocytes after the first exposure to an antigen?
They survive long term as memory cells.
How does the sympathetic system affect peristalsis and intestinal secretions?
It slows down peristalsis and production of intestinal secretions.
What is the process of phagocytosis?
The engulfing of pathogens and their destruction by digestive enzymes in lysosomes.
What is the function of glial cells?
To support and maintain the neurones.
What happens in converging neural pathways?
Impulses from several neurons travel to one neuron, increasing sensitivity to signals.
What are the two groups typically found in a randomised trial?
One group receives the new treatment, while the other (control group) receives the standard treatment or a placebo.
What is the transmission method for Smallpox?
Contact.
What are lymphocytes?
White blood cells involved in the specific immune response that respond to specific antigens.
What are non-self antigens?
Fragments of a pathogen's antigen displayed on infected cells.
What does the Serial Position Effect indicate about recall?
Recall is best for items shown at the end (recency effect) and those at the start (primacy effect), while items in the middle are recalled poorly.
What happens when acetylcholine binds to receptors on skeletal muscle fibers?
It causes muscle fibers to contract, e.g., peristalsis.
What triggers an increase in endorphin production?
Severe injury, prolonged exercise, stress, and certain foods.
What are the two main components of the Central Nervous System (CNS)?
The brain and the spinal cord.
What are inactivated vaccines?
Vaccines made from pathogens that are killed or inactive, such as the Diphtheria and Tetanus vaccines.
What occurs during a secondary exposure to the same antigen?
Memory cells rapidly give rise to a new clone of specific lymphocytes.
What do phagocytes release to attract more phagocytes?
Cytokines.
What is the role of the parasympathetic system in relation to the sympathetic system?
It changes the actions of the sympathetic system in the opposite way.
What does the cell body of a neurone contain?
The nucleus and most of the cytoplasm.
What is a characteristic of reverberating neural pathways?
They allow repeated stimulation of the pathway, similar to an echo.
What is a placebo?
A dummy treatment, such as a sugar pill that looks like the drug being tested.
What are antigens?
Molecules, often proteins, located on the surface of cells that trigger a specific immune response.
What is the Herd Immunity Threshold for Rubella?
80 - 85%.
What is one role of T lymphocytes?
To destroy infected cells by recognizing pathogen antigens.
What happens to the first few objects in a list during recall?
They have enough time to be rehearsed and are often transferred to Long-Term Memory (LTM).
What effect does acetylcholine have when it binds to heart muscle fiber receptors?
It has an inhibitory effect, reducing contraction rate and strength.
What are the three main processes involved in memory?
Encoding, storage, and retrieval.
What does the Peripheral Nervous System (PNS) consist of?
The Somatic Nervous System (SNS) and the Autonomic Nervous System (ANS).
What is an example of a vaccine made from parts of a pathogen?
HPV vaccine against cervical cancer and Hepatitis B.
What are the three types of neural pathways mentioned?
Diverging, Converging, and Reverberating neural pathways.
What is the primary function of dopamine?
Induces feelings of pleasure and reinforces particular behavior by activating the reward pathway in the brain.
What are cytokines?
Protein molecules that signal specific white blood cells to accumulate at the site of infection.
What is the role of the cell body in a neurone?
It acts as the control center of cell metabolism.
What is myelin?
The fatty tissue that insulates an axon.
How does antibody production during the secondary response compare to the primary response?
It is greater and more rapid during the secondary response.
What is an example of diverging neural pathways?
The divergence of motor neurons for fine motor control of fingers.
What is the 'placebo effect'?
When people feel better after receiving a placebo because they believe they are receiving real treatment.
What is the role of membrane receptors on lymphocytes?
They are specific to one antigen and activate the lymphocyte when bound by that antigen.
What is apoptosis?
Programmed cell death induced by T lymphocytes.
What happens in a community with no immunization during an outbreak?
An outbreak occurs.
What is the Working Memory Model?
It suggests that short-term memory is complex, capable of processing and storing data, and has subdivisions for different types of data.
What is the role of neurotransmitters in the nervous system?
They relay messages from nerve to nerves within and outside the brain.
What is encoding in the context of memory?
The process of converting sensory images into a form that the brain can process and store.
What types of neurons are found in the Somatic Nervous System (SNS)?
Sensory and motor neurons.
What are weakened pathogen vaccines?
Vaccines made from weakened forms of pathogens, such as Measles, Mumps, and Rubella vaccines.
What does the reward pathway involve?
Neurons that secrete or respond to dopamine.
What role do lysosomes play in phagocytes?
They contain digestive enzymes that destroy engulfed bacteria.
What do dendrites do?
They receive nerve impulses and pass them towards the cell body.
Where are neurons connected in various ways?
In the Central Nervous System (CNS).
How does the presence of myelin affect impulse transmission?
It greatly increases the speed at which impulses can be transmitted.
How do converging pathways increase sensitivity in the retina?
Several rods converge to one rod bipolar cell, allowing enough neurotransmitter to be released.
What does the immune system do during a secondary response to a pathogen?
It destroys the invading pathogen before symptoms appear.
Why are double-blind trials important?
To ensure neither the subjects nor the researchers know who is receiving the trial treatment, preventing bias in results.
What is the outcome when some of the population is immunized but not enough?
Not enough to confer herd immunity.
How do T lymphocytes cause infected cells to undergo apoptosis?
By releasing proteins that produce self-destructing enzymes.
What happens when a specific lymphocyte is activated by an antigen?
It is said to have been 'selected' by the antigen.
What is a key characteristic of Long-Term Memory (LTM)?
LTM has unlimited capacity and holds information for a long time.
What does storage refer to in memory?
The retention of information over a period of time, which can range from 30 seconds to a lifetime.
What connects neurons with other neurons, muscle fibers, and endocrine glands?
A synaptic cleft.
What are dead pathogen vaccines?
Vaccines made from dead pathogens, such as Poliomyelitis and Hepatitis A.
What are the two systems that make up the Autonomic Nervous System (ANS)?
The Sympathetic and Parasympathetic Systems.
What happens after a phagocyte recognizes a bacterium?
It adheres to the bacterium and engulfs it in the cell membrane.
When is the reward pathway activated?
When an individual engages in behavior that is beneficial to them, such as eating when hungry.
What is an axon?
A single nerve fibre that carries nerve impulses away from the cell body.
What is myelination?
The process by which myelin develops around axon fibers.
What are neurotransmitters?
Chemicals that relay messages across the synaptic cleft.
What role do rods play in the retina?
They are visual receptors that increase sensitivity to low levels of illumination.
What is the result of a critical portion of the population being immunized?
Protects most community members.
What is the significance of group size in trials?
A suitable group size reduces experimental error and helps establish statistical significance.
What happens to the remains of cells after apoptosis?
They are cleared away by phagocytosis.
What does HIV attack in the immune system?
T lymphocytes.
What is a clonal population in the context of lymphocytes?
A population of identical lymphocytes formed through repeated division after antigen binding.
What is retrieval in memory?
The recovery of stored material, involving the recall of information from short-term or long-term memory.
What does the Peripheral Nervous System contain?
Peripheral nerves.
What is an adjuvant in vaccines?
A substance mixed with antigens to enhance the immune response and make the vaccine more effective.
How are items organized during encoding in Long-Term Memory?
Items are organized into categories such as personal facts and useful skills.
What can cause neurotransmitter-related disorders?
Alterations in the production, release, breakdown, or re-uptake of a neurotransmitter.
What is formed around the engulfed bacterium?
A vacuole.
What are axon terminals?
Divisions at the end of an axon.
When is myelination complete?
At birth, but it continues from birth to adolescence.
What determines whether a signal is excitatory or inhibitory?
The type of receptor.
What is an example of a motor response initiated by the nervous system?
Hormone release.
Name two examples of neurotransmitters.
Acetylcholine and Noradrenaline.
What is the significance of reverberating pathways in physiology?
They are used in repetitive activities such as breathing.
What is compared at the end of a trial?
Results from the two groups to determine statistically significant differences.
What condition does the depletion of T lymphocytes due to HIV lead to?
AIDS (Acquired Immune Deficiency Syndrome).
What is sensory memory?
A very short-lived memory that retains all visual and auditory input for about 0.5 seconds.
What is herd immunity?
When a critical portion of a community is immunized, protecting most members from contagious diseases.
What does the Somatic Nervous System (SNS) control?
The voluntary movement of skeletal muscles.
What occurs when lysosomes fuse with the vacuole?
They release digestive enzymes that destroy the bacterium.
What is the role of B lymphocytes?
They produce antibodies against antigens, leading to the destruction of pathogens.
Name two examples of neurotransmitter-related disorders.
Alzheimer’s disease and Depression.
What is the function of the myelin sheath?
To insulate the axon and increase the speed of impulse conduction.
Why are responses to stimuli slower in the first two years of life?
Because many more neurons are myelinated during this period.
Where are neurotransmitters stored?
In vesicles in the axon endings of the presynaptic neuron.
What is a key characteristic of individuals with AIDS?
They have a weakened immune system and are more vulnerable to opportunistic infections.
What is the capacity of short-term memory (STM)?
Can hold about 7 items for approximately 30 seconds.
What types of neurons are included in the Somatic Nervous System?
Sensory and Motor Neurons.
How does herd immunity protect non-immune individuals?
It reduces the probability of contact with infected individuals, thus providing indirect protection.
What is the end result of phagocytosis?
The bacterium is degraded and destroyed.
What are the two types of drugs used to treat neurotransmitter disorders?
Agonists and Antagonists.
What do long axon fibres have that aids in impulse conduction?
A myelin sheath.
What are antibodies?
Y-shaped proteins with receptor binding sites specific to a particular antigen on a pathogen.
What is the primary function of the cerebral cortex?
It is the center of conscious thought.
What happens to the myelin sheath in certain diseases?
Diseases like Multiple Sclerosis destroy the myelin sheath, causing a loss of coordination.
What happens to neurotransmitters upon the arrival of an impulse?
They are released into the synaptic cleft.
What is the difference between HIV and AIDS?
HIV is a virus that weakens the immune system, while AIDS is a condition resulting from severe immune system weakening due to HIV.
What happens to information in short-term memory after 30 seconds?
It is either transferred to long-term memory or lost through displacement or decay.
What do Sensory Neurons do?
Take impulses from sense organs to the Central Nervous System (CNS).
How do recreational drugs affect neurotransmission?
They alter mood, cognition, perception, and behavior.
What factors determine the threshold for establishing herd immunity?
Type of disease, effectiveness of the vaccine, and density of the population.
What do agonists do?
They bind to and stimulate specific receptors, mimicking the action of a neurotransmitter at a synapse.
How does the cerebral cortex affect behavior?
It recalls memories and alters behavior in light of experience.
What does each clone of B cells produce?
One type of antibody molecule that is specific to one type of antigen.
What role do glial cells play?
They support neurons physically and produce the myelin sheath.
How do neurotransmitters interact with the postsynaptic neuron?
They diffuse across the cleft and bind to receptors on the postsynaptic neuron's membrane.
What is the body's localized defense response to physical injury called?
Inflammatory response.
What is 'chunking' in memory?
A technique to improve STM capacity by grouping several smaller units into a meaningful unit.
Why is establishing herd immunity important?
It helps reduce the spread of diseases.
What are the effects of recreational drugs on mood?
They can make individuals feel happier, more confident, or more aggressive.
What do Motor Neurons do?
Take impulses from the Central Nervous System (CNS) to muscles and glands.
What is the role of antagonists?
They bind to specific receptors, blocking the action of the neurotransmitter at a synapse.
How are antibodies transported in the body?
Once released into the blood and lymphatic system, they are transported to the infected area.
What are the distinct regions of the cerebral hemisphere responsible for?
They are responsible for sensory, motor, and association areas concerning language, personality, imagination, and intelligence.
In which direction do nerve impulses travel due to neurotransmitter release?
In one direction only.
What is a synapse?
The connection point where neurons connect with other neurons or muscle fibers.
What was the status of diphtheria before the vaccination program in 1940?
It was a very common bacterial infection and one of the leading causes of death in children.
How can rehearsal help with memory?
By repeating information to yourself, either silently or out loud, to aid memorization.
How do recreational drugs impact cognition?
They can impair the ability to carry out complex mental tasks.
