(Unit 2) The Immune System - Part One

[updated post-quiz]

Mucous Membranes

An external defense that secretes mucus.

Mucus

A sticky substance that traps microbes and other particulate matter.

Circulatory System

an internal defense that allows immune cells to travel

Lymphatic System

store acquired immunity and innate immunity

Macrophages

A type of phagocyte that indeterminately kills microbes by 'eating' them and delivering them to the acquired immunity.

Acquired Immunity

Has very specific responses, needs to be trained, includes B cells and T cells.

B Cells

Mature in the bone marrow, recognize foreign antigens using antibodies, and produce secreted antibodies when activated. They are more effective in eliminating bacterial infections

Antibodies

Recognize and bind to intact antigens (bacteria and viruses), acting as a flag to alert the innate immune response.

Plasma B Cells

produce and secrete antibodies

Memory B Cells

Become activated if the same antigen appears at a later date, trigger a quicker and more potent immune response

T Cells

mature in thymus, and are more effective at eliminating viral infections (because they can kill infected cells)

Helper T Cells

alert the immune system

Killer T-Cells

kill infected cells

Antigen

A molecule recognized by the immune system, such as bacteria

Viruses

Non-living intracellular parasites that require a host cell to reproduce, composed of a genome and a protein shell.

genome of a virus

the genetic material of a virus, which can be either DNA or RNA, and contains the instructions for viral replication.

the protein shell of a virus

protects the viral genome and allows the virus to attach to the host cell

Mono

Caused by the Epstein-Barr virus; symptoms include sore throat, fever, chills, headache, nausea, and pervasive fatigue.

Hepatitis

An inflammation of the liver; symptoms include fever, headache, nausea, and jaundice.

Bacteria

Unicellular organisms that are usually extracellular pathogens, often producing toxins that cause symptoms.

Staph Infections

Caused by bacteria, normally present on skin, and responsible for many hospital-acquired infections.

Strep Throat

a bacterial infection that causes sudden extremely sore throat, difficulty swallowing, inflamed tonsils, fever, and headache.

Meningitis

a bacterial infection that causes the inflammation of the meninges (membranes that surround the central nervous system). Symptoms: sudden fever, severe headache, or stiff neck.

Pneumonia

most common cause is Streptococcus pneumoniae (bacterial, but also can be viral). Symptoms: chronic cough, chest pain, chills and high fever.

Peptic Ulcers

a chronic lesion or wound in the lining of the stomach or upper part of the small intestine

Helicobacter pylori

a type of bacteria that causes peptic ulcers by damaging the protective lining of the stomach and promoting inflammation

Protists

unicellular parasites (molecularly similar to human cells), that cause infections that are slightly less common.

Giardia

an extracellular parasite, caught by drinking untreated water. Symptoms: gastrointestinal syndromes, begin 1-2 wks after initial exposure.

Malaria

caused by plasmodium, an intracellular parasite. Symptoms: anemia, fever and chills, nausea, flu-like symptoms.

African Sleeping Sickness

caused by trypanosoma—carried by the African tsetse fly

Parasitic Worms

Platyhelminthes or flatworms

Fungi

can cause yeast infections, athlete's foot, or toxic mold.

Yeast infections

The most dangerous one is Candida alibcans

Athlete's Foot

scaly, flaky, itchy skin.

Toxic Mold

some release mycotoxins, which produce allergies and respiratory ailments.

Allergies

a hypersensitive immune response to a non-pathogenic antigen