Weeks 1-4 Flashcards
(92 cards)
1
Q
What 3 things does the cell membrane do for living organisms
A
-maintain homeostasis
-metabolize
-respond to environment
2
Q
TF viruses are living
A
F
3
Q
why arent viruses considered living
A
rely on a host to reproduce
4
Q
why dont antibiotics kill viruses
A
Antibiotics target the cell wall which viruses dont have
5
Q
what is taxonomy
A
classification of organisms
6
Q
what is a taxon
A
group of organisms classified together
7
Q
what is the basal taxon of a tree
A
the “most different” organism
8
Q
what are thing that look similar but dont have an evolutionary relationship
A
analogous
9
Q
what are homologues (in a phylogenic tree context)
A
share structure bc of a common ancestor
10
Q
what are 3 requirements for life
A
-water
-energy
-bioenergetic elements
11
Q
put them in order.
-small organic molecs
-H2O,H2,CO2,CH4
-large organic molecs
A
-H2O,H2,CO2,CH4
-small organic molecs
-large organic molecs
12
Q
chemical evolution is driven by ____,____,_____,
A
radiation, heat, low temp , etc
13
Q
what is metabolism
A
building up, breaking down, energy harnessing + generating
14
Q
what is some evidence of LUCA
A
- lighter isotopes produced from living organisms found in carbon
- traits found in bacteria + archaea
15
Q
TF did Luca have genetic material
A
Yes
16
Q
prokaryotes include
A
bacteria + archaea
17
Q
how can we tell the difference between proks
A
DNA and RNA analysis
18
Q
what are some differences between archaea and bacteria + eukarya
A
Archaea
- phytanyl sidechain
- ether linkage
- monolayer
Bacteria + Archaea
- regular sidechain
- ester linkage
- phospholipid bilayer
19
Q
- gram +ve bacteria stain_____ and have ____ peptidoglycan in their cell wall
- gram -ve stain ___ and have ____ peptidoglycan
A
- purple, more
- pink less
20
Q
why is the gram +ve bacteria darker
A
the purple stain gets stuck in the cell wall whereas the gram -ve it doesnt
21
Q
TF 4/5 Phyla of bacteria are gram -ve
A
T
22
Q
why are gram -ve bacteria harder to treat
A
-antibiotics dont kill them
-membranes are quite toxic
23
Q
what are the varieties of cell shapes
A
- cocci (round
- bacilli (rods)
Spirilli (spiral shaped)
24
Q
what are 3 main metabolic functions
A
-capture, convert and/or generate energy
-obtain carbon to build up proteins lipids, nucleic acids and carbohydrates.
-eliminate waste
25
what is a heterotroph
eat Carbon rich sources (animals, fungi, some proks)
26
what is an autotroph
fix carbon from CO2 to prod glucose
27
what is a phototroph
obtain energy from light
28
what is a chemotroph
obtain energy from breaking down inorganic compounds (CO2)
29
what are the classes of obtaining carbon
heteotroph + autotroph
30
what are the classes of obtaining energy
phototroph+chemotroph
31
how can some proks live in extreme environments
have a "capsule" around cell that helps resist the environment
32
what is an endospore
spore that is dormant for very long time until the environments becomes favourable
33
TF some proks enter an viable but not culturable (VBNC) state when environment is not good and go back to normal when conditions improve
T
34
how do proks adapt to the environment so easily
reproduce thru binary fission so offspring is identical, but its due to rapid reproduction, mutations, and Horizontal gene transfer (HGT)
35
Which statement is NOT correct about cyanobacteria?
They:
A. Form long filaments (colonies).
B. Produce oxygen (O2) through photosynthesis.
C. Fix carbon from carbon dioxide (CO2) in the
atmosphere.
D. Are heterotrophs.
E. Fix nitrogen from nitrogen gas (N2) in the atmosphere.
F. Form specialized cells
D
36
How did Oxygen become abundant in the atmosphere
When cyanobacteria became common, they drastically increased the concentration of oxygen in the atmosphere.
37
TF the "oxygen revolution" benefitted many organisms
F,
only benefitted aerobic organisms, i.e. a small fraction of organisms present 2.5 billion years ago. other organisms were gone extinct (but it did give rise to eukaryotes)
38
what are methanogens
-anerobic chemoautotrophs
- oxidize H2 for energy
-source of C
-produce methane
-live in anerobic environments
39
what are extremophiles
methanogens that can live in very extreme environments
40
what are 3 classes of extremophiles
thermophiles (live in hot waters)
mesophiles(thrive in moderate conditions)
Halobacteria (extremely salty environments)
41
TF mesophiles can be found in the digestive system
T
42
what unique protein does halobacteria have to prevent water loss
halorhodopsin ( pump Cl into cell to prevent water loss)
43
Bifidobacterium are ______trophs, gram __ bacteria, can be found in _______, breaks down the _____ sugar
chemoheterotrophs
+ve
digestive system
lactose
44
Rhizobium are gram ____, _______trophs, live in _______,provide ____ to the host plant
-ve
chemoheterotroph
root cells of some plants
nitrogen
45
TF when the Rhizobium provides nitrogen to the plant the plant returns cellulose to the rhizobium
F provides glucose not cellulose
46
Which type of prokaryotes contribute to both the carbon and nitrogen cycles?
Decomposers
47
when did the first eukaryotes arise
about 2 bil yrs ago
48
what led to eukaryotes sucess
Oxygen increase in the atmosphere
49
how were some anerobic proks able to survive after the oxygen boom (2)
- survived in O2 poor envvironments
- or formed an endosymbiotic relationship with another prok, to make a more complex cell
50
what is the leading theory of eukaryotic cell formation
endosymbiosis (archaea and bacteria merged - bacteria turns into the mitochondria)
51
what is some evidence that mitochondria were bacteria cells before endosymbiosis
mitochondria have their own circular DNA
52
what are some advantages of eukaryotic cells
- The nucleus protects the DNA (fewer mutations)
- Ability to reproduce sexually
- organelles keep cellular functions separated and more efficient and allows cell to form specialized tissues
53
what are some advantages of asexual reproduction
- Fast
- simpler
- dont need mate
- everyone produced offspring
54
what are some advantages of sexual reproduction
- more variety
- more controlled cell divisions
- can repair DNA (thru recombination)
55
how are 2 ways meiosis coulda have evolved
- from mitosis
- from prokaryotic sex
56
what are 3 traits of haploid dominant life cycles
- exists mostly as haploid organism
- often reproduce asexually
- Fusion of 2 haploids happen before sexual reproduction
57
what are 3 traits of a diploid life cycle
- exists usually as diploid
- cannot reproduce asexually
- haploid gametes only produced during sexual reproduction
58
what are 2 traits of alternation of generations
- alternate between haploid and diploid
- haploid gametophyte produces gametes while diploid sporophyte produce spores
59
why are protists no longer considered a kingdom
too diverse, protists in every supergroup
60
what do all protists have in common (4)
- eukaryotic
- mostly unicellular
- reproduce sexually
- live in moist areas or form mutualistic or parasitic relationships
61
how did the first photosynthesizing eukaryotes evolve
a protist formed and endosymbiotic relationship with a cyanobacteria about 1.5 bil yrs ago
62
what did the first photosynthetic eukaryotes evolve into
red and green algae
63
what group do red and green algae belong to
archaeplastida
64
why are red and green algae different colours
they photosynthesize at different depths, red algae grow deeper
65
what are the differences between primary and secondary endosymbiosis
Primary
- A eukaryotic cell engulfs a prokaryotic cell
Secondary
- A eukaryotic cell engulfs another eukaryotic cell (that already has a plastid).
66
TF primary symbiosis has occurred twice
T
67
what are mixotrops
can photosynthesis (photoautotroph) + can feed on organic molecules (chemoheterotroph)
68
what photosynthetic pigments are in Fucus (1 special)
- chlorophyll a
- chlorophyll c1 and c2
- Fucoxanthin*
69
TF marine life produces less than 25% of the O2 we breathe
F, they produce more than 50%
70
TF multicellularity evolved once and spread throughout the tree
F, multicellularity evolved independently in several different groups
71
what are the 6 groups that have multicellularity
Animals
Fungi
Brown algae
Red algae
Green algae
Plants
72
what are the advantaged of multicellularity (3)
- allows organism to grow larger (more competitive)
- can continue living even when individual cells die
- more complexity
73
TF fungi are chemoautotrophs
T (but they use extracellular digestion)
74
what is a sapotroph
- obtain carbon from breaking down dead organic material on soil or food
75
TF the cell wall of fungi is made of cellulose
F, made of chitin
76
TF most fungi reproduce asexually and only do sexually when they have to
T
77
TF fungi can produce spores sexually but not asexually
F, they can do both
78
fungi do not produce sperm and egg, so how do they reproduce sexually
hyphae of opposite mating type will fuse together
79
what is a monokaryotic hyphae
contains one haploid nulceus
80
what is a dikaryotic hyphae
Contain 2 haploid nuclei
81
what are 5 phylum of Fungi
- basidomycota
- ascomycota
- glomeromycota
- zygomycota
- chitridomycota
82
what are some traits of basidomycota (mushrooms)
- septate
- sexual
83
what are some traits of ascomycota
septate
asexual
84
what are some traits of glomeromycota
asexual
aseptate
terrestrial (cant live on their own so they live w plant roots)
85
what are some traits of zygomycota
aspetate
asexual
moist terrestrial environments
86
what are some traits of chritridomycota
mostly unicellular
aseptate
asexual
mostly aquatic
87
which 1 of the 5 phyla of fungi are not decomposers and parasitic
glomeromycota
88
TF all 5 phyla of fungi can form a mutualistic relationship with something
T
89
what is a clade
a group of organisms that includes a common ancestor and all of its descendants. It represents a single branch on the tree of life
90
how did fungi transition from water to land
- formed mutualistic relationship with algae and cyanobacteria which can colonize land w no soil
- also with plant roots to facilitate water and nutrient uptake
91
TF fungi can break the surface of rock to increase weathering of rock into mineral soil
T
92
