6.3 & 11.1

When activated some lymphocytes produce antibodies and other lymphocytes act as memory cells. Which of the following best describes the role of memory cells?

• They store antigens from the pathogen for lymphocytes to use as a template for antibodies in the future.

• They remember the antigen on the pathogen and tell the lymphocytes how to respond if it is re-encountered.

• They quickly clone to form a group of phagocytes if the pathogen is re-encountered.

• They quickly clone to form a group of plasma cells if the pathogen is re-encountered.

What causes antibiotic resistance?

• Evolution of human cell processes that stop the antibiotic working.

• Production of memory cells which digest antibiotics.

• Evolution of a dangerous reaction to the antibiotic in some humans.

• Evolution of bacterial processes that stop the antibiotic from being effective.

There are limits to the effectiveness of antibiotics.Why is this?

• Bacteria are not affected by antibiotics, only viruses.

• Only one species of bacteria is affected by a single antibiotic.

• Only some types of viruses and bacteria are affected by antibiotics, because of the evolution of resistance.

• Viruses are not affected because they have no metabolism, and some bateria have evolved resistance.

Why do antibiotics have little or no effect on human cells?

• Antibiotics can not block the metabolic processes in eukaryote cells.

• Human cells have a protective plasma membrane which prokaryote cells don't have.

• Antibiotics can only affect cells below a certain size.

• Antibiotics are made of proteins which cannot pass through the plasma membrane.

Why are antibiotics used to treat bacterial infections but not viral infections?

• They kill viruses.

• They stop a specific process in the host cell metabolism.

• They slow down the whole metabolism of bacterial cells.

• They act on one or more prokaryote cellular processes.

Which of the following is an example of non-specific immunity?

• Recognition of the pathogen antigen by white blood cells.

• Antibody production.

• Antibiotic treatment.

• Endocytosis of pathogens by white blood cells.

Which of the following initiates an immune response if it enters the human body?

• Antibody

• Antihistamine

• Glycogen

• Antigen

If the skin is broken then a blood clot forms to seal this cut.

What is the role of fibrinogen in the process of blood clotting?

• Fibrin turns into fibrinogen.

• Fibrinogen is converted to fibrin.

• Fibrinogen is converted into thrombin

• Fibrinogen is converted into prothrombin

Which is the best description of a pathogen?

• A cell that produces antibodies.

• An organism that is affected by a disease.

• An organism or virus that is affected by antibiotics.

• An organism or virus that causes disease.

If the immune system has reacted to a pathogen two months ago, this is said to give "specific immunity".

Which of the following is the best description of what happens when a person with specific immunity has an infection of the same antigen?

• Erythrocytes clot quickly in fibrin.

• Macrophages engulf all types of pathogens

• Lymphocytes quickly clone to produce antibodies that neutralize pathogens with the same antigens.

• Memory cells activate phagocytes which start engulfing bacteria.