Test 3 P1 Flashcards
What are some main characteristics of fungi?
Heterotrophic, domain Eukarya, cells walls made of chitin, act as decomposers or saprobes
What does it mean if something is heterotrophic?
does not photosynthesize & cannot produce own food
What are saprobes?
organisms that get nutrients from decaying organic matter using exoenzymes
What are the 2 stages of fungal function?
Vegetative & reproductive
Are fungi multi or unicellular?
Some uni (yeasts) while most are multi. Dimorphic fungi switch back & forth b/w being uni & multi.
What is fungi cell structure?
Cell wall made of chitin & glucans (both polysaccharides) which provide structural support & prevent water loss
Multicellular fungi are made of what?
Hyphae - branching filaments that make up the mycelium or vegetative growth of a fungus
Reproductive sac that contains spores is called?
Sporangium
Which carbohydrate is usually found in fungal cell walls?
Chitin
The bulk of basidiomycetes (mushrooms) are found where?
underground
What fungi classification has chitin & cellulose in its cell walls?
Chytridiomycota
Which phylum is associated w/ the mutualistic relationship b/w plant roots?
Glomeromycota
Fusion of cytoplasm w/o fusion of nuclei is called?
plasmogamy
Ascomycetes are characterized by how many ascospores?
8
The wall dividing cells in a fungal filament is called…
Septum
Phylum Nematoda (roundworms) are ____
Pseudocoelomates
What is a defining characteristic of Planaria (a species found in phylum Platyhelminthes).
hermaphroditic (has both male & female reproductive system) AND has one opening that serves as both the mouth & the anus
Platyhelminthes exhibit what type of body plan?
Acoelomate
Spiders are found in the subphylum ____
Chelicerata
The worm that causes trichinosis after consuming undercooked pork is a _____
roundworm
The phylum with the most known species is ____
Arthropoda
What environment is best for fungus?
Moist & slightly acidic environments. Most are obligate aerobes while some are obligate anaerobes
What is the difference between aerobes & anaerobes?
Aerobes: require oxygen to survive
Anaerobes: oxygen will kill them
How does fungi reproduce?
Some reproduce asexually through budding, fragmentation, or producing asexual spores. Some can reproduce sexually (2 kinds)
What are the 2 kinds of sexual reproduction in fungi?
- Plasmogamy - 2 haploid cells fuse, producing a dikaryotic cell where 2 haploid nuclei coexist in a single cell.
- Karyogamy - nuclei from 2 cells fuse to form a diploid zygote nucleus.
What are the 5 fungal classifications?
- Ascomycota (sac fungi)
- Basidiomycota (club fungi)
- Chytridiomycota (chytrids)
- Glomeromycota
- Zygomycota (conjugated fungi)
What are Ascomycota (sac fungi)?
Has sac-like structure called ascus that contains haploid ascospores. 8 ascospores in each ascus & fruiting body called ascocarp. Undergoes sexual & asexual reproduction
What are Basidiomycota (club fungi)?
Fruiting body called basidiocarp. Each basidium produces 4 haploid basidiospores. Undergoes sexual reproduction
What are Chytridiomycota (chytrids)?
Simplest fungi. Have both cellulose & chitin in cell walls. Tend to live in aquatic environments & only fungi to still have a flagellum
What are Glomeromycota?
Most found in mutualistic relationships with roots of trees. Do NOT reproduce asexually & do not survive w/o plant roots
What are Zygomycota (conjugated fungi?
Only one zygospore is produced in each sporangium, undergoes both sexual & asexual reprod.
Fungi have developed many mutualistic relationships with what other kingdoms?
Plants - mycorrhizae
Protists/bacteria - lichens
Animals - ants, farm, fungi
What are the unifying characteristics of animals?
Heterotrophic, multicellular, complex tissue structure & typical life cycle is diplontic (somatic diploid cells, haploid gamete cells)
What are the 4 types of animal tissues?
Epithelial, muscle, connective, nervous
How do animals reproduce?
Most undergo sexual reproduction & some asexual through budding or fragmentation
What is parthenogenesis in animal reproduction?
“Virgin beginning” which is where an animal can develop from a gamete w/o fertilization. Ex. male bees come from unfertilized eggs
What are the developmental steps in animal reproduction?
Zygote –> Blastula –> Gastrula
Zygotes (fertilized eggs) develop through a series of stages to form germ layers.
Blastopore can either become the anus or mouth
What is the Homebox in animal reproduction?
(Hox) genes that are DNA sequences that are “master control genes” which make genes that determine animal structure. Similar across many different animal phyla; control body structure .
- All vertebrates have 4+ sets of Hox genes, white invertebrates only have 1 set.
- Master control genes control transcription factors for expression of sets of other genes.
What are the main ways to classify animals?
Symmetry & embryological development.
Describe the basics of embryological development
- Germ layers form during gastrulation, giving rise to different parts of the body.
Endoderm-lining of digestive tract
Mesoderm-bones, muscles, organs
Ectoderm-skin, nerves
Animals w/ 2 layers are diploblasts
Animals w/ 3 layers are triploblasts
Animals with 3 layers that are triploblasts have what sub-categories & they are based on what?
Sub-categories are based on if they have a coelum or not.
- Acoelomate (does not have body cavity)
- Eucoelomate or Coelomate (true body cavity surrounded by mesoderm)
- Pseudocoelomate (body cavity b/w endoderm & mesoderm
Triploblastic coelomates can be further divided into groups based on where the mouth develops from, what are 2 ways to occur?
- if blastopore (1st opening formed during gastrulation) develops into mouth, these animals are known as protostomes.
- If the blastopore develops into the anus, these animals are known as deuterostomes.
What is the Ediacaran Period?
635-543 mya evolved from protists. Fossil impressions look like feathers/coins. Recent findings may show animal life developed earlier in Cryogenian period (650 mya)
What does the hypothesis about the cause of the Cambrian Explosion say?
Rising oxygen levels, increases in ocean Calcium, ecological relationships b/s species/changes to food webs, genetic/developmental advances (Hox control gene)
What are the 3 different areas that formed after Cambrian explosion?
Paleozoic Era - encouraged adaptations to land
Mesozoic Era - dinosaurs
Cenozoic Era - rise of mammals & flowering plants
