Class Notes (1,036,088)
US (406,746)
GVSU (487)
BMS (82)
Lecture 6

BMS 212 Lecture Notes - Lecture 6: Acanthamoeba, Chrysophyta, Entamoeba

8 pages54 viewsFall 2016

Department
Biomedical Sciences
Course Code
BMS 212
Professor
Aaron Baxter
Lecture
6

This preview shows pages 1-2. to view the full 8 pages of the document.
Survey of Eukaryotes (Fungi, Protozoa and Algae)
I. Fungi
- Cell wall made of chitin
- Not photosynthetic no chloroplasts
- Environmentally diverse can live in harsh conditions in terms of pH, oxygen
concentrations, salinity, moisture, etc.
- Significant in nutrient recycling, symbiotic relationships, food/drug production
Structure of fungi
Two main types
a. Molds and Fleshy Fungi
- Seldom individual cells
Hyphae: the body of the structure, composed of long, branched,
tubular filaments
- Two classes of hyphae
Septate: divided into separate cells by crosswalls called
septa
Coenocytic: cells are not divided by septa
- Two types of hypha
Vegetative hypha: obtain nutrients in the ground
Reproductive or aerial hypha: reproductive structures above
ground
Mycelium: The overall structure, composed of intertwined hyphae
forming a tangled mass
b. Yeasts
- Non-filamentous
- Generally unicellular
- Oval or spherical
- Two types of yeasts
Fission yeasts: crosswall forms in the center of the cell for
equal division
Budding yeasts: cells unequally proportioned
Pseudohypha
- Forms when buds fail to detach
find more resources at oneclass.com
find more resources at oneclass.com
You're Reading a Preview

Unlock to view full version

Only half of the first page are available for preview. Some parts have been intentionally blurred.

- Appears filamentous
*pseudohypha are environmentally dependent in
the environment they tend to stay unicellular, in the
host they become pseudohyphic to help push deeper
into the tissues
Dimorphic fungi
- Shift between unicellular and filamentous forms
Nutrition
heterotrophic gain their nutrients from organic substrates
saprobes feed off of dead organisms
parasites feed off of live hosts
- Cause mycosis (fungal disease)
- Form haustoria to penetrate tissues and withdraw nutrients
*haustoria: like a straw, degrades the tissue and sucks it up*
Reproduction
- Fungi most often reproduce using spores.
- All fungi undergo asexual reproduction, and it is believed that all are capable
of sexual reproduction as well.
Two types of spore formation
a. Asexual spore formation
- three subtypes of asexual spores
- Sporangiospores
- A membrane sac called a sporangium forms and fills with
spores
- This forms on a stalk called the sporangiophore, at either the
tips or off the sides of the hyphae
- Conidiospores (conidia)
- These are the most common
- Spores are produced at the tips or off the sides of the hyphae,
but not in a sac
- Some form chains called conidiophores, some form a spore-
bearing projection called a sterigma
- Chlamydospores
- Spore forms within the hypha
find more resources at oneclass.com
find more resources at oneclass.com
You're Reading a Preview

Unlock to view full version

Only half of the first page are available for preview. Some parts have been intentionally blurred.

- Once it has matured, the hypha breaks and releases the spore
cell
b. Sexual spore formation
1. Two haploid cells (known as + and -, not male and female) fuse and
form a dikaryon (two nuclei)
2. The nuclei fuse, the cell is now considered diploid
3. Meiosis restores the haploid state
4. Spore partition, maturation, and release occurs
- Three common types of sexual spores
- zygospores (zygosporangium)
- The gametes form at the tips of the hypha
- They come into contact and fuse into the dikaryon
- This forms the zygosporangium, which produces a haploid
sporangium that fills with spores
- The spores are released
- ascospores
- Hyphal tips fuse
- Dikaryons form and remain in this state for some time
- They become diploid when the nuclei fuse and then form
haploid cells
- Haploid cells line the ascus (pl. asci, these are just sacs that
hold spores) of the fruiting body, these may undergo
mitosis and cytokinesis to form 8 ascospores
- The asci open and release the ascospores
- basidiospores
- The + and fuse in the soil
- Replication and growth occurs, producing a basidiocarp
(mushrooms)
- In the gills of the mushroom the haploid cells become
diploid
- Meiosis occurs and results in four haploid nuclei that form
four basidiospores
*This is as far as we got in lecture, Professor Baxter cut out the
rest of these notes I filled out the rest from the book*
Lichens
- A symbiotic relationship between fungi and photosynthetic microorganisms
(usually cyanobacteria, but sometimes green algae)
- The hyphae of the fungus surround the photosynthetic organisms and give them
nutrients, water, and protection
find more resources at oneclass.com
find more resources at oneclass.com
You're Reading a Preview

Unlock to view full version


Loved by over 2.2 million students

Over 90% improved by at least one letter grade.