Diversity Flashcards
(39 cards)
1
Q
What is an animal?
A
- multicellular
- large
- heterotrophic
- motile
- polarisation along anterior-posterior locomotory axis
- epithelial cells
- ach/cholinesterase system
- monophyletic clade
2
Q
What are the major groups of animal phyla?
A
- porifera
- ctenophores
- placozoans
- cnidarians
- bilaterians
3
Q
List the features of porifera
A
- loosely organised
- no true organs
- no specialised cell layers
- spicules - hard body elements
- choanocytes - feeding cells
4
Q
List the features of placozoans
A
- no mouth
- no gut
- diploblastic
- contractile fibre cell in middle
5
Q
List the features of ctenophores
A
- radial symmetry
- diploblatic –> ectoderm and mesoderm
- mesoglea - ECM
- complete gut
- 8 ctenes
6
Q
List some of the features of cnidarians
A
- jellyfish, sea anemones, corals
- gastrovascular cavity
- typically sessile (polyp) and motile (medusa) life stages
- nematocytes
7
Q
List some of the features of bilaterians
A
- triploblastic - exoderm, endoderm, mesoderm
- protostomes - mouth first, blastopore, mouth
- deuterostome - mouth second, blastopore, anal opening
8
Q
Which organisms are protostomes?
A
- flatworms
- annelids
- mollusks
- nematodes
- arthropods
9
Q
Which organisms are deuterostomes?
A
chordata
10
Q
List some features of flatworms
A
- may be free living or parasitic
- most are tapeworms/flukes –> vertebrates
- mostly gut endoparasites
- A lophotrochozoan (RNA)
- Taenia asiatica
- Schistosoma Spp
11
Q
List some features of annelids
A
- segmented wormlike bodies
- seperate ganglia for each segment
- thin permeable body for gas exchange
- lophotrochozoan
12
Q
List some features of mollusks
A
- most diverse lophotrochozoan
- large foot
- main organs in a visceral mass
- mantle convers visceral mass
- octopus spp
- squid, slugs, snails, muscles, oysters
13
Q
List some features of nematodes
A
- ecdysozoan group of protosomes
- roundworms - most abundant
- thick multi-layered cuticle
- un-segmented
- Caenorhabditis elegans
- Ascaris lumbricoides
14
Q
List some features of arthropods
A
- ecdysozoans
- segmented bodies
- exoskeleton –> chitin, waterproof
- muscles on inside
- jointed and specialised appendages
15
Q
List some features of chordata
A
- dorsal hollow nerve cord
- tail that extends beyond anus
- a dorsal supporting rod - notocord
- lancelets, tunicates, vertebrates
16
Q
What was the green revolution?
A
- norman borlaug
- food yields doubled in india and pakistan
17
Q
How can we increase Food security?
A
- increase yield –> conventional breeding, improved agronomy, GM plants
- decrease waste
- crops adapted to deal with climate change
- pest/disease control
- healthier foods
18
Q
How can crops be adapted to deal with climate change?
A
- drought-resistant
- flooding-resistant
- flooding-tolerance
- salt-resistant
19
Q
How is golden rice healthier?
A
- high levels of B-carotene (vitamin A precursor_
- stops children going blind from vitamin A deficiency
20
Q
What is meant by plant plasticity?
A
- plant cells are undifferentiated
- can regenerate whole new plants
21
Q
Describe the basic plant evolution
A
- green algae ancestor
- mosses
- ferns
- cone-bearing plants
- flowering plants
22
Q
List some examples of non-vascular plants
A
- liverworts
- hornworts
- mosses
23
Q
List some examples of pre-seed vascular plants
A
lycophytes –> club mosses, spike mosses, quillworts
pterophytes –> ferns, horsetails, whisk ferns
24
Q
What are gymnosperms?
A
plants with seeds but no flowers –> ginko tree, conifers, cycads
25
What is a cotyledon?
a leaf-like structure formed in the embryo
monocot, dicot
26
List some examples of monocots
grasses, palms, orchids
27
List some examples of dicots
broad-leafed plants, leafy crops
28
What is the main component of cell walls in fungi?
chitin - formed by N-acetylglucosamine units
29
What is ergosterol
- in cell membranes of fungi and protozoa
- precursor of vitamin D2
- target for antifungal drugs
- indicator of fungal presence in soil
30
What is the role of hyphae
efficient absorption of nutrients
31
What is the difference between saprotrophy, necrotrophy and biotrophy?
saprotrophy - dead plant and animal tissue
necrotrophy - kill and use before, during and after death
biotrophy - living tissue
32
What are the roles of saprotrophs?
- nutrient cycling
- nutrient translocation
- humus formation
- soil structure and stability
33
List the types of wood decay
stain - mainly ascomycetes
brown rot - mainly basidiomycetes
white rot - mainly basidiomycetes
soft rot - mainly ascomycetes
34
List the features of brown rot
- simple compounds, cellulose and hemicellulose are used
- lignin not used
- hyphae lie on cell wall in lumen
- H2O2 diffuse into wall
35
List the features of white rot
- utilises all compounds
- hyphae lie on cell wall in lumen
- forms erosion grooves
- can completely decompose wood to CO2 and H2O
36
List the features of soft rot
- simple compounds, cellulose and hemicellulose used
- lignin removal is absent or slow and incomplete
- type 1 occurs in S2 layer producing cavities
- type 2 occurs in lumen giving erosion grooves
37
Describe the action of necrotrophs
- kill by enzymes
- toxins
- vascular wilts
38
What are lichens?
- mutualists --> biotrophy
- relationship between a photobiont and a mycobiont
- a new organism
39
What are mycorrhizas?
- association between root of plants and fungi
- angiosperms, gymnosperms, pteridophytes
