Chapter 12 - Eukaryotic Microbes

Question 1

What is a protozoa?

Answer 1

An organism that reproduces asexually through fission, budding, or shizogony. Has 200,000 species, Divided into Clades.

There are Excavata, Euglenozoa, amebae, apicomplexa, and ciliates

Question 2

Excavata

Answer 2

lack mitochondria, move by flagella or undulating membranes. Examples include Giardia, trichomonas, and trichonympha

Question 3

Euglenozoa

Answer 3

Move by flagella, are hemoflagellates. Examples include Trypanosoma.

Question 4

Amebae

Answer 4

move by pseudopods, and an example is entamoebae histolytica

Question 5

Apicomplexa

Answer 5

In definitive host, it sexually reproduces. In an intermediate host, there is asexual reproduction. An example is Plasmodium Vivax

Question 6

Ciliates

Answer 6

They move by cilia and are rarely pathogenic. An example is Paramecium

Question 7

Differentiate between Intermediate host and definitive host

Answer 7

The intermediate host is where the parasite undergoes asexual reproduction ( us the human with plasmodium vivax/malaria)

The definitive host is where the parasite reproduces sexually.

Question 8

Cellular Slime Molds

Answer 8

Eukaryotic cell that resembles amebae. During the life cycle, cellular slime molds live and grow by ingesting fungi and bacteria by phagocytosis. When things get rough, cellular slime molds come together as one large structure, but germinate when things are ok again.

Question 9

Plasmodial Slime Molds

Answer 9

Exists as a mass of protasm with many nuclei called a plasmodium. Moves as a giant amebae, engulfs organic debris and bacteria. Changes speed and direction to evenly disperse nutrients.

Question 10

Common features of Algae

Answer 10

all are photosynthetic, mostly aquatic, all can reproduce asexually. Heterogeneous features: some single celled, some multicellular. Some can reproduce sexually as well as asexually

Question 11

Brown Algae

Answer 11

Multicellular, includes kelp, produce algin (a food thickener)

Question 12

Red Algae

Answer 12

Most are multicellular, Produce Agar

Question 13

Green Algae

Answer 13

Unicellular and multicellular; probably gave rise to terrestrial plants.

Question 14

Diatoms

Answer 14

Unicellular; produce toxins that are concentrated in shellfish and fish that ingest them.

These toxins cause disease in humans. Example: paralytic shellfisch poisoning etc.

Question 15

What is Lichen, How do the two parts support each other?

Answer 15

Lichen is algae wrapped fungus. The fungi protects the algae, and the algae takes in sunlight to make sugars for the fungi.

Question 16

How are fungi differentiated from other eukaryotes?

Answer 16

Fungi are chemoheterotrophs, absorb nutrients, can tolerate a pH of 5, are aerobic, can grow in dry places (resistant to osmotic pressure), and have low moisture.

Question 17

Mold

Answer 17

Multicellular; have hyphae that look for nutrients.Septate have cross walls dividing the hypahe into cell like units. Coenocytic lack septa. Hyphae grow by elongating at the tips.

Question 18

Yeast

Answer 18

Single celled, divide by binary fission or budding, dimorphism (can be male/female)

Question 19

Sexual Reproduction in Fungi

Answer 19

Two different haploid mating types:

1. Plasmogymy: two haploid cells fuse
2. Karyogomy: nuclei fuse, results in diploid reproductive structure.

**meiosis results in haploid spores

Question 20

Zygomycota

Answer 20

Reproductive Structures: zygospore, sporangium. Example: rhizopus

Question 21

Ascomycota

Answer 21

she has sexual and asexual lifestyles. Sexual=saclike ascus (ascospores); asexula=condida (spores)]These cause plant and human diseases.

Question 22

Basidiomycota

Answer 22

Life Cycle: asexual - hyphae fuse to form myceia, sexual =club shaped bacteria; examples= mushrooms and cryptococcus neoformans

Question 23

What is deuteromycota and why it is not a phylum

Answer 23

artificial catch all; nor reproductive structure (anamorphs) most currenlty classified as ascomycota

Question 24

Fungi and human disease

Answer 24

Immune response

2. Mycotoxin
3. Infection
   Mycoses

Question 25

why are some fungal infections in humans difficult to treat?

Answer 25

Because drugs that affect fungal cells, may also AFFECT ANIMAL CELLS.