defense against infectious diseases, homeostasis, sexual production, integration of body systems

What is a pathogen?

A disease-causing organism, typically including viruses, bacteria, fungi, and protists.

Which organisms are not known to cause disease in humans?

Archaea.

What is an infectious or communicable disease?

A disease capable of being transmitted from one organism to another.

What major observation did John Snow make during the cholera outbreak in London in 1854?

He found that deaths from cholera were linked to people living close to a contaminated water pump.

What was the cause of the cholera outbreak discovered by John Snow?

The water was polluted by sewage containing cholera bacteria.

What did Ignaz Semmelweis observe about childbed fever in hospitals?

More deaths occurred in the ward with medical students who did not wash their hands after performing autopsies.

What is the primary function of the skin in defense against pathogens?

It serves as both a physical and chemical barrier to microorganisms.

What is the epidermis covered with that helps protect against pathogens?

Keratinized protein from dead cells, forming an impervious layer.

How can pathogens enter the body through the skin?

At locations not covered by skin, especially if the skin is broken or scratched.

What role do mucous membranes play in the immune defense?

They secrete sticky mucus that traps incoming pathogens.

What is the function of cilia in mucous membranes?

They carry trapped pathogens up and out of mucous-lined tissues.

What protective feature of the stomach helps defend against pathogens?

Stomach acid kills most bacteria.

How do enzymes in tears contribute to defense against pathogens?

They destroy bacteria.

What is the first step in the blood clotting process?

Platelets collect at the site of a cut and clump together.

What is thromboprotein?

A clotting factor released by clumping platelets that converts prothrombin into thrombin.

What does thrombin do in the blood clotting process?

It converts fibrinogen into insoluble fibrin at the site of the cut.

What happens to platelets when they stick to damaged tissue?

They change shape from sacks to flattened discs, sealing off cuts.

What is the role of fibrin in blood clotting?

Fibrin forms a mesh that stabilizes the blood clot.

What can moist folds in the skin become a home for?

Fungi that cause infections like athlete's foot.

What is a common way that the larvae of schistosoma enter the body?

They can burrow through the skin when people bathe in infected water.

What is the significance of careful observation in treating diseases?

It can lead to important discoveries and advancements in treatment.

What forms a mesh that traps red blood cells and forms a clot?

Fibrin

What is the main defense of the body against pathogens? +

The immune response +

What are the molecules that trigger an immune response called?

Antigens

What is the first layer of the immune system that responds to pathogens?

Innate immune system

What type of immune response involves specialized white blood cells called lymphocytes?

Adaptive immunity

What are the long-lived white blood cells formed during the first exposure to a pathogen called?

Memory cells

What type of movement do phagocytes use to engulf pathogens?

Amoeboid movement

What are the two types of lymphocytes?

B-lymphocytes (B-cells) and T-lymphocytes (T-cells)

What do B-cells produce? +

Antibodies

What are the Y-shaped proteins that bind to antigens called?

Antibodies (immunoglobulins)

What is the process called when antibodies make soluble antigens insoluble?

Precipitation

What role do Helper T-cells play in the immune response?

They communicate with other white blood cells to signal the presence of a specific antigen.

What is clonal selection of B-cells?

The generation of a large number of plasma cells that produce one specific antibody type.

What happens during the primary immune response?

The first response to a pathogen is relatively long and no memory cells are present.

What is the first identified cause of acquired immune deficiency syndrome (AIDS)?

Human Immunodeficiency Virus (HIV)

How is HIV primarily transmitted? +

Through blood, semen, vaginal fluids, and breast milk.

What type of cells does HIV infect? +

CD4+ T-cells +

What is the result of a low CD4+ T-cell count?

A weak immune response to pathogens, making the individual susceptible to opportunistic infections.

What are antibiotics used for?

To slow down or kill bacteria.

Who discovered penicillin?

Alexander Fleming

What is one reason for pathogenic resistance to antibiotics?

Mutations in bacteria that allow them to survive antibiotic treatment.

What is the significance of the Rh antigen in blood transfusions?

It determines compatibility between donor and recipient blood types.

What happens if blood transfusions are not compatible?

Agglutination may occur.

What is the role of hydrolytic enzymes in phagocytes?

They digest foreign material after engulfing it.

What triggers the release of histamine during inflammation?

The immune response to pathogens.

What is the function of antibodies in neutralization?

They mask dangerous parts of a pathogen.

What is the main function of T-cells in the immune system?

To activate B-cells and other immune cells.

What happens to most plasma cells after an infection is cleared?

They undergo apoptosis, but some remain as memory cells.

What is the role of macrophages in the immune response?

To engulf antigens and activate helper T-cells.

What strain of bacteria is resistant to a large range of antibiotics?

MRSA (Methicillin-resistant Staphylococcus aureus)

How can MRSA be treated?

With intravenous vancomycin

What is a major challenge faced by the pharmaceutical industry regarding antibiotics?

Developing new antibiotics faster than bacteria develop resistance.

What are zoonotic diseases? +

Diseases that can transfer from other species to humans. +

What bacterium causes tuberculosis in humans?

Mycobacterium bovis

How can humans be exposed to tuberculosis?

Through ingestion of unpasteurized milk and infected meat products.

What is the main symptom of tuberculosis?

Lung damage.

How is rabies transmitted to humans?

Through direct contact with saliva or nervous system tissues, usually via a bite.

What happens once symptoms of rabies appear?

The disease is fatal.

What is Japanese encephalitis and how is it transmitted?

A viral disease transmitted through the bite of a mosquito that infects brain tissues.

What triggers the development of immunity in vaccines?

Antigens or nucleic acids (DNA or mRNA) that code for antigens.

What is herd immunity?

When a large percentage of people in a given area achieve immunity, reducing the chance of disease spreading.

What is the formula for percent change?

(change/original number) x 100.

What is the formula for percent difference?

(difference/average) x 100, where average is (first value + second value) / 2.

What is homeostasis?

A control process that maintains physiological factors within preset limits.

Which systems are involved in maintaining homeostasis?

The nervous and endocrine systems.

What is the role of insulin in blood glucose regulation?

Insulin decreases blood glucose concentrations by triggering cells to convert glucose to glycogen.

What is the role of glucagon in blood glucose regulation?

Glucagon raises blood glucose concentrations by converting glycogen back to glucose.

What are the symptoms of hypoglycemia?

Convulsions and coma.

What is Type 1 diabetes?

An autoimmune disease where the immune system destroys the beta cells of the pancreas.

What is Type 2 diabetes?

A condition where body cells do not respond properly to insulin, leading to insulin resistance.

What are the primary temperature sensing tissues in humans?

Thermoreceptors in the skin and hypothalamus.

What happens to arterioles in the skin when body temperature rises?

They dilate to allow more blood flow to the skin, losing excess heat.

What is the response of sweat glands when body temperature rises?

They produce more sweat, which evaporates to cool the body.

What is the role of epinephrine in body temperature control?

It causes vasoconstriction, resulting in goosebumps to retain heat.

What is thermoregulation?

The process of maintaining internal body temperature within a set point.

What is the advantage of being an ectotherm?

They do not need to metabolize food to generate body heat.

What is the primary way endotherms can increase body temperature?

Through muscular activity during exercise or work.

What is the main defense mechanism of the body against pathogens? -

The immune response -

What are antigens?

Molecules that trigger an immune response

What is the first layer of the immune system?

The innate immune system

How does the innate immune system respond to pathogens?

It responds to broad categories of pathogens and does not change throughout a person's lifetime.

What type of cells are activated in the innate immune response?

Phagocytes

What is adaptive immunity?

The second layer of the immune system that develops over time after exposure to specific antigens.

What are lymphocytes?

Specialized white blood cells involved in the adaptive immune response.

What are memory cells?

Long-lived white blood cells formed during the first exposure to a specific pathogen that can be activated quickly upon re-exposure.

What is the role of phagocytes in the immune response?

They engulf pathogens through endocytosis.

What do B-lymphocytes (B-cells) produce? -

Antibodies -

What happens to B-cells once they are activated?

They become plasma cells and secrete antibodies.

What are antibodies?

Y-shaped proteins that bind to specific antigens.

How do antibodies help in destroying pathogens?

Through precipitation, agglutination, neutralization, inflammation, and complement activation.

What is the function of Helper T-cells? +

They communicate with other white blood cells to activate specific B-cells. +

What is clonal selection in B-cells?

The process where a small number of B-cells respond to a specific antigen and divide to produce many plasma cells.

What is the primary immune response?

The initial response to a pathogen that is relatively slow and does not involve memory cells.

What is the secondary immune response?

A faster and stronger response to a previously encountered pathogen due to memory cells.

What is HIV?

Human Immunodeficiency Virus, which causes Acquired Immune Deficiency Syndrome (AIDS).

How is HIV transmitted? -

Through blood, semen, vaginal fluids, and breast milk. -

What cells does HIV infect?

CD4+ T-cells.

What is antibiotic resistance?

When bacteria evolve to survive exposure to antibiotics.

What is a zoonotic disease?

A disease that can transfer from animals to humans.