BIO UNIT 4 PATHOGENS

two classifications of pathogens

cellular

non cellular

types of cellular pathogens (4)

bacteria, fungi, worms, protozoa

types of non cellular pathogens (2)

viruses and prions

are bacteria prokaryote or eukaryote

prokaryote

are bacteria unicellular or multicellular

unicellular

how to bacteria affect the organism

Bacteria can cause disease through the production of toxins and enzymes which either affect the functioning of cells or cause their death.

how do bacteria reproduce

asexually through binary fission

Are fungi prokaryotic or eukaryotic?

Eukaryotic

Are fungi unicellular or multicellular?

both

how do fungi affect the organism

exploiting weakened immune systems, utilizing specialized structures (hyphae/yeast) to invade tissues, and secreting enzymes or toxins that break down host cells for nutrients

How do fungi reproduce?

sexually and asexually

are worms prokaryotic or eukaryotic

eukaryotic

are worms unicellular or multicellular

multicellular

how do worms affect an organism

by acting as parasites, relying on a human or animal host for survival and nourishment while causing disease. They damage tissues, steal nutrients, and induce immune dysfunction.

how do worms reproduce

sexually

Are protozoa eukaryotic or prokaryotic?

Eukaryotic

are protozoa multicellular or unicellular

unicellular

how do protozoa affect an organism

protozoa have many different mechanisms of action - for example, some can inhibit nucleic acid synthesis, protein synthesis, and various stages of cellular respiration.

How do protozoa reproduce?

sexually and asexually

are viruses eukaryotic or prokaryotic

viruses are not made up of cells and are considered non living

are viruses multicellular or unicellular

viruses are not made up of cells and are considered non living

what are viruses made up of

singular particles - DNA or RNA enclosed in a protein coat (capsid)

how do viruses reproduce

Viruses can reproduce only by infecting living cells, replicating inside and then lysing the cell causing further damage

what is a viroid (3)

Infectious pieces of naked RNA

Only infect plants

subclass of virus

what are viroids composed of

RNA only, circular strand

how do viroids affect organisms and what type do they affect

by targeting protein synthesis in plants

what is a prion

an infectious protein

simple proteins that are different forms of the proteins that exist in the nervous tissue of a larger organism

how do prions reproduce

They cause other normal cellular proteins of the same type to misfold into the infectious form

are prions eukaryotes or prokaryotes

prions are proteins that do not have any genetic material

are prions multicellular or unicellular

prions are proteins that do not have any genetic material

how do prions affect an organism

cause similar proteins to fold into the same shape as the prion, the misfolding can cause tissues to lose function and structure

protozoan

unicellular eukaryotic parasites that require a host to produce in

oomycetes

protista microbes (eukaryotes) that commonly cause disease in plants

arthopods

large invertebrates (eukaryotes )

do arthopods reproduce sexually or asexually

sexually

what is a disease

conditions that hinder the normal function of an organism

infectious diseases (2)

caused buy particular agents called pathogens

pathogens can be cellular or non cellular

what is a pathogen

A microorganism that causes disease

non infectious diseases (2)

caused by environmental or genetic factors

what is the immune system

bodily system that responds to disease and pathogens

what is the immune system composed of

variety of innate molecules like specific cells tissues and organs

what are antigens

Antigens are usually proteins that can be recognised by the immune system, may generate an immune response when detected by the body if non self

immunogens

antigens that are able to trigger an immune response.

types of structures of antigens (4)

proteins - ones produced in flagella

lipids - glycolipids

carbohydrates - glycoproteins

nucleic acids

what is an allergen

type of antigen that produces an abnormally aggressive immune response (such as dust mite, pollen, dander and food allergies)

how does the immune system respond to allergens

recognises the allergens as non self, initiating a strong immune response, even though they are non pathogenic - cannot cause the body harm

mild allergy symptoms

Skin rashes, swelling, nasal drainage, itchy eyes.

severe allergy symptoms

Anaphylactic shock, low blood pressure, cardiac arrest.

self antigens

antigens of the host organism

the immune system should recognise self antigens but not respond

non self antigens

antigens from pathogens or foreign material, the immune system should recognise non self antigens and respond

MHC stands for

major histocompatibility complex

types of MHC (2)

I

II

MHC I

expressed on all nucleated cells of an organism

MHC II

expressed on specialised cells of the immune system

what are MHCs made of primarily

proteins

autoimmune disease

a disease in which the immune system attacks the organism's own cells because it responds to its self antigens

what are non self antigens recognised as

foreign

what is special abt MHC proteins

differ between individuals - therefore can be identified as foreign