ch 12 microbio, unit three

algae, protozoa, fungi

microscopic unicellular algae

macroscopic multicellular algae

what are the two groups of algae?

organized vascular system

simple reproductive structures

what does algae lack compared to plants?

carbohydrates

what does algae mainly produce?

freshwater or saltwater and sometimes in soil

where is algaes habitat?

Phytoplankton

free floating unicellular algae in aquatic environments

Food source

#1 oxygen producer.

flagella

algae are propelled by?

mainly cellulose

rigid

what type of cell wall does algae have?

cell walls of algae

what is agar derived by?

chloroplasts

how do algae perform photosynthesis?

Binary fission (asexual)

single celled algae reproduce by

Fragmentation (asexual)

multicellular filamentous algae reproduce by

Fusion of gametes

• Gametes are flagellated and motile

some algae can reproduce sexually using…

not direct cause of disease

• foodborne intoxications

How are algaes medically relevant?

Pyrrophyta (dinoflagellates)

produce algal blooms, called red tide, in the ocean

certain dinoflagellates

produce toxins

Paralytic shellfish poisoning

caused by domoic acid

• accumulates in shellfish and crabs

Symptoms

• nausea, vomiting, diarrhea, abdominal cramps, and neurological symptoms such as memory loss

with muscle contraction and can lead to death following impaired respiration

some toxins can interfere with…

1. —Unicellular

2. —Lack cell walls

3. —Non-photosynthetic

4. —Motile

5. —Generally reproduce by asexual fission

6. —Require large amounts of moisture no matter what their habitat

common features of protzoa

• —Flagella

• —Cilia

• —Pseudopodia

motility in protozoa is achieved by

consume bacteria and algae in soil

—decompose wastes in sewage

serve as food for larger species

protozoa are important because…

polymorphic

some protozoa can assume —morphologically distinct forms of a single species at different stages of the life cycle

(Ex: Plasmodium)

cyst (protozoa)

protection in poor environments and allows for dispersal of organisms

resting form

Trophozoite

vegetative or feeding form

Cyst form protozoa

resting/dormant

sexually or asexually

protozoa can reproduce…

asexual reproduction of protozoa

—Most reproduction is achieved through binary fission

Shizogony(asexual)

some protozoa divide by multiple fissions in which the nucleus divides a number of times

then the cell produces many small single-celled organisms

sexual reproduction of protozoa

At certain points in their life cycle, protozoa may reproduce sexually.

This creates diversity among the offspring

Trypanosoma brucei (protzoa)

African sleeping sickness

Giardia lamblia (protzoa)

“traveler’s” or “camper’s” diarrhea

Trichomonas vaginalis (protzoa)

causes Trichmoniasis

strawberry cervix

Leishmania (protzoa)

Leishmaniasis (disease)

Plasmodium (protzoa)

malaria

Toxoplasma gondii (protzoa)

Toxoplasmosis

Cryptosporidium (protzoa)

causes Cryptosporidiosis (disease)

a diarrheal disease

Medically significant protozoa

1. —Trypanosoma brucei- African sleeping sickness

2. —Giardia lamblia- “traveler’s” or “camper’s” diarrhea

3. —Trichomonas vaginalis- Trichmoniasis

4. —Leishmania- Leishmaniasis

5. —Plasmodium- malaria

6. —Toxoplasma gondii- Toxoplasmosis

7. —Cryptosporidium- Cryptosporidiosis

asexual reproduction plasmodium

Asexual reproduction occurs in stages where it is important to increase numbers,

• polymorphic

occurs by schizogony (or multiple fission) in RBCS or liver cells

sexual reproduction of plasmodium

sexual reproduction occurs in the stage where it is important to increase diversity

• polymorphic

occurs by mosquito biting infected human and ingests gametocytes, gametocytes merge to form zygote, results in sporozoites in salivary glands

organic compounds and carbon source

• chemoorganoheterotrophs

what do fungi require for energy?

fungi species can either be

• —anaerobic

• aerobic

—

chitin

what is the cell wall of fungi?

no, not at any life cycle

do fungi have flagella?

fungi

principal decomposers of carbon compounds on earth

same as bacteria

morphological forms of fungi

Yeast- single

Mold- filamentous

Dimorphic- grow as yeast or mycelia

Yeasts

single form of fungi

mold

filamentous fungi

• Hypha- single filament

• hyphae- plural

septate

if cells within hyphae are distinguishable

• individual cellular compartments by cross-walls called septa

non-septate

if hyphae have no separating membrane

mycelium

collection of hyphae is one place

“root system of fungi”

dimorphic

—fungi that is capable of growing either as yeast-like cells or as mycelia,

depending upon environmental conditions.

---

• —High nutrients (Ex: lungs)- yeast, warm conditions

• —Low nutrients (Ex: soil)- mold, cold conditions

Lichens (symbiotic)

fungus with photosynthetic organism (alga or cyanobacteria).

• Fungus provides protection, foundation for growth, and absorbs water and minerals for both parties.

• The photosynthetic organisms provides organic nutrients

Mycorrhizae (symbiotic)

fungus within the roots of certain plants (~80% of vascular plants).

Fungus increases the absorptive power of the root.

Leaf cutter ants (symbiotic)

worker ants provide vegetation for mold farms to grow, and in turn use the fungus as their food source

Lichens-fungus with photosynthetic organism

Mycorrhizae-fungus within the roots of certain plants

Leaf cutter ants

Symbiotic- 2 organisms living close together benefiting

what are the 3 symbiotic forms of fungi?

wine, beer, bread, and most importantly penicillin and other medicine

what can fungi produce?

genetically modified yeast

produce human growth hormone, hep B vaccine, insulin

mycoses

fungi disease. medically important fungi include..

• —Candida albicans

• —Coccidiodes immitis

• —Cryptococcus neoformans

• —Histoplasma capsulatum

• —Pneumocystis jirovecii

—Arthropods

insects, ticks, lice, and mites

Vectors for transmission of MO

—Helminths

nematodes (roundworms), cestodes (tapeworms), and trematodes (flukes).

primitive

cause disease by invading host tissue

Pediculus humanus (arthropod)

head lice

a disease causing arthopod

Phthirus pubis(arthropod)

crab louse

disease causing arthopod

sexually transmitted

Sarcoptes scabiei (arthropod)

a mite that causes scabies, an itchy rash commonly found between the fingers, under the breasts, and in the genital area.

Transmitted through physical contact

Disease causing nematode(Helminths)

—Necator americanus- hookworm disease

—Trichinella spiralis- trichinosis

—Cestodes(Helminths)

—Taenia solium- pork tapeworm

—Trematodes(Helminths)

—Schistosoma mansoni- schistosomiasis

Necator americanus (—Nematodes)

hookworm disease

Trichinella spiralis (—Nematodes)

causes trichinosis (disease)

Taenia solium (—Cestodes)

pork tapeworm

Schistosoma mansoni (—Trematode)

schistosomiasis (disease)

yeast

What form of dimorphic fungi grow in warm high nutrient conditions?

mold

What form of dimorphic fungi grow in cold low nutrient conditions?