Exam 1 Flashcards
1
Q
Define biology
A
The scientific study of life
2
Q
What are the sub disciplines of biology
A
Zoology - study of animals
Microbiology- study of bacteria and viruses
Botany - study of plants
Mycology - study of fungi
Ecology - study of how organisms interact with environments
3
Q
What is life’s hierarchy of organization
A
Biosphere Ecosystem Community Population Organism Organ system Organs Tissue Cells Molecules Atoms
4
Q
Define the biosphere
A
All living things on earth are within the biosphere
The biosphere consists of all environments on earth that support life
Includes land and water
5
Q
Define the ecosystem
A
Encompass all living organisms and non living matter existing within a particular environment
Includes all components of the environment with which the living organisms interact like air soil sunlight and water
6
Q
Define the community
A
These are the groups of organisms composed of a number of different species that live within an ecosystem
7
Q
Define the population
A
These are all individuals of a particular species living within a particular area
Ex) all lady bugs in the park
8
Q
Define the organism
A
This is the individual unit of the population
Ex) a lady bug from their population or a deer from their population ext
9
Q
Define the organ systems
A
This is a group of several organs which work together to preform specific functions
Ex) nervous system
10
Q
Define the organs
A
A structure comprised of tissue which together as a group works to preform specific functions
Ex) the heart
11
Q
Define tissues
A
These are made of similar cell types and each tissue has a specific function
Each organ is made up of several different tissue types
12
Q
Define the cells
A
These are membrane bound and the individual units of living matter
Ex) liver tissue is comprised of a liver cell called a hepatocyte
13
Q
Define molecules
A
Made up of a cluster of atoms
Ex) DNA, protein, sugar molecules
14
Q
Define atoms
A
These are the smallest unit of matter
Molecules are comprised of atoms
Ex) nitrogen atoms ext
15
Q
Organisms and their environment
A
Living organisms interact with their environment
Organisms within an ecosystem interact with both the living and the non living components of their environment
16
Q
What do producers do for their ecosystem
A
Provide food for the other organisms present
17
Q
Define producers
A
Includes plants and other photosynthetic organisms
Can make their own food
18
Q
Define consumers
A
They eat plants and other animals to obtain energy
Can not make their own food
19
Q
Define decomposers
A
Breakdown wastes and dead organisms recycling nutrients so that they can be used for biosynthesis
Ex) fungi bacteria small animals in the soil
20
Q
What are the two ways in which ecosystems can be characterized
A
1) recycling of chemical nutrients
2) energy flow
21
Q
What is the recycling of chemical nutrients
A
The basic chemicals needed for life like carbon nitrogen oxygen ext flow from air and soil to plants animals and decomposers and then back to the air and soil
22
Q
What is energy flow
A
Energy is constantly gained and lost from an ecosystem
Energy enters an ecosystem when light from the sun is absorbed by plants and other photosynthetic organisms
Energy exits the ecosystem as heat
23
Q
Is the structure and function of a cell correlated
A
Yes they are an emergent property
24
Q
What are cellular functions
A
Responding to environment changes
The ability to take in and use energy
Regulating their own internal environments
The ability to produce and maintain its complex organization
The ability to give rise to new cells -reproduction growth and repair
25
What are two main cell types
Prokaryote cells
| Eukaryote cells
26
Define a prokaryote
```
No true nucleus
Unicellular
Smaller then eukaryotes
Less complex with no membrane bound organelles
Ex) bacteria
```
27
Define eukaryote
Unicellular or multicellular
Larger
Has nucleus and membrane bound organelles
Ex) animal cell
28
What features do all organisms share in common
Genetic material present as DNA
| Cells are the simplistic unit of the organism
29
How is DNA organized
Into functional units called genes and the DNA itself is made of individual chemical units called nucleotides
30
What are the four nucleotides which make up DNA
Adenine
Thymine
Cytosine
Guanine
31
What are feature that are common among all life forms
```
Complex organization
Highly regulated internal environment
Ability to grow and develop
Ability to take in and use energy
Ability to respond to environmental changes and stimuli
Ability to reproduce
Evolution adaptations
```
32
How many known species are named and how many are estimated to be around all together
1.8 million named
| 10-400 million could be the true amount of species
33
What is taxonomy
The branch of biology that names and classifies these species into groups based on similarity
34
What are the three domains of life
```
Domain bacteria (prokaryotes)
Domain archaea (prokaryotes)
Domain eukarya (eukaryotes)
```
35
What are the four kingdoms of Eukarya
```
Kingdom Protista
- single called and Algae
Kingdom Plantae
- photosynthetic plants
Kingdom Fungi
- molds yeasts and mushrooms
Kingdom Animalia
- animals vertebrates and invertebrates
```
36
Who came up of the idea of evolution
Charles Darwin
37
What was Charles darwins idea of evolution
Species present today arose from ancestral species
He explained the unity of life (decent from a common ancestor) and the diversity of life (modifications specified became)
38
What did Darwin propose that the mechanism of evolution was
Natural selection
39
What is natural selection
Based on the observation of unequal reproduction success
The environment selects for certain traits
This results in the accumulation of favourable traits in a population over time
40
Explain the process of natural selection
Individuals within a population have varied traits which are inheritable
Not all offspring will survive and only those that do will be given the chance to reproduce
The individuals with the most desirable traits will be able to survive and reproduce an the resulting population will therefore be enriched with organisms that have these traits
41
What is evolutionary adaptation
All organisms have specific adaptations that have evolved as a direct result of natural selection
42
What is antimicrobial resistance
Developed as a result of natural selection
A resistant species develops in a short time period
Ex) bacteria that makes you sick learns to fight the medicine you take
43
Define adaptations
Inherited traits that function to enhance an organisms ability to survive in a specific environment
44
What are some pre-Darwinian evolutionary theories
Greek philosophers believed that life changed gradually over time
Aristotle view was that species were perfect and permeant
The mid 1700s fossils proved that previous life forms differed from those today
Jean Lamarck said that life forms evolve but believed it had to do with the use and not use
45
How did Charles Darwin discover his theories
Was a captain of a ship and collected plants animals and fossils from the shores of South America and he noted the adaptations and differences from those of the Brazilian grasslands and those on islands and noticed Island and land species where similar but different
46
Define artificial selection
The modification of species by selecting and breeding those individuals that posses desired traits
47
Define natural selection
Similar to artificial selection but occurs in nature
48
What are two key observations of natural selection
1) members of a population vary in their traits and most traits are inherited from parents to offspring
2) all species are capable of producing more offspring then the environment can support
49
What did the two observations of natural selection reveal
1) individuals whose traits provide them higher probability of surviving and reproducing in a given environment tend to leave more offspring behind then other individuals
2) this unequal production of offspring will cause favourable traits to accumulate in an environment
50
Define fossils
Provide comparisons between past organisms and present organisms- provided strong evidence for evolution
Fossils are usually only replicas of an organism
- forms a mold
51
What are the 6 different types of fossils
1) fossilized skull
2) cast fossils
3) trace fossils
4) fossilized organic matter
5) an insect buried in a tree
6) ice preserving
52
What is a fossilized skull
Hard parts of the organism containing minerals such as bone that remains as fossils
53
What are cast fossils
Replicas of the organism formed when the organism decays and water and dissolved minerals fill its place
54
What are trace fossils
Footprints burrows or other behavioural remnants
55
What is fossilized organic matter
When a something like a leaf becomes imprinted
56
How does a tree act as a fossil
The resin hardened and preserved things protecting it from decomposition
57
How does ice preserves
Because of its extreme temperature decomposers are either unable or extremely slow at decomposing
58
What is the fossil record
The sequence in which fossils appear in the layers of sedimentary rock
Oldest sediments becomes buried below into rock
Strata (layers formed in the rock) the youngest layers on top
Relative age can be determined by the layer it was found
Oldest known fossils are prokaryotes
59
What is other evidence for evolution
1) biogeography
2) comparative anatomy
3) cooperative embryology
4) molecular biology
60
What is biogeography
The geographical distribution of species can suggest that organisms evolve from a common ancestor
61
What is comparative anatomy
Comparing body structures in different species reveals homology suggesting a common ancestor
62
Define homology
The similarity in characteristics that result from a common ancestor
63
Define homologous structure
Structures that are functionally different but have similar structures because of a common ancestor
64
What is comparative embryology
Organisms go through similar embryonic stages
| Comparison of the structures that appear during the development of different organisms suggest common ancestry
65
What is molecular biology
Individuals that arose from a common ancestor have greater similarity in their DNA and protein then do unrelated individuals
Species that are closely related have a much higher percentage of identical amino acid sequences
Comparing amino acid sequences can help prove evolution
66
What are evolutionary trees
Each branch point represents the common ancestor of the lineages beginning there or to the right of it
A hatch mark represents a homologous characteristic shared by all groups to the right of the mark
Homologous structures both anatomical and molecular can be used to determine the. Ranching sequence of the tree
67
What is the smallest unit that can evolve
Populations
68
Define population genetics
The study of how populations change genetically over time
69
What do scientists that study population evolution focus on
The gene pool
70
Define the gene pool
The total collection of genes in a population at any given time
For most genes there are at least two alleles in the pool
71
Define micro evolution
The gradual change in the gene pool of a population over time
When allele frequencies are changing in a population over a number of generations evolution occurs in its smallest scale
72
What is generation of genetic variation
New alleles can be created by mutation
Or
Variation by sexual recombination
73
Define mutation
A change in the nucleotide sequence of DNA
74
Define sexual recombination
This generates variation by shuffling alleles during meiosis
75
What are three factors that contribute to evolution
1) natural selection
- leads to differential reproductive success and can alter allele frequencies
2) genetic drift
- a change in the gene pool of a population due to chance can alter allele frequencies and cause the bottleneck effect
3) gene flow
- the movement of individuals between populations leads to gain or loss of alleles
76
What is the bottleneck effect
Floods fires and earthquakes can kill large numbers of people leaving behind small amount of survivors that is unlikely to have the same genetic makeup as the original population
Drastic reduction in population size and change in allele frequency
77
What is the founder effect
results when a few individuals colonize a new environment such as an isolated island
The smaller the new group the less likely the genetic makeup of the new population will resemble the original population
Refers to the differences between the gene pool of the new population and the gene pool of the original population
78
What are endangered species
```
Have reduced variation by
- the bottle neck effect
- loss of genetic variability due to over hunting and habitat loss
- a high level of inbreeding occurs
- humans alter the environment
Ex) cheetah population
```
79
How does natural selection alter variation
1) stabilizing selection
- favours the intermediate phenotypes
2) directional selection
- acts against individuals at one of the phenotype extremes
3) disruptive selection
- this favours individuals at both extremes of the phenotypic range
80
What is sexual selection
Occurs when individuals with certain characteristics are more likely to obtain mates
A form of natural selection
Leads to the evolution of secondary sex characteristics
These characteristics may provide individuals with a mating advantage
81
What are four reasons that natural selection produces less then perfect organisms
1) selection can only act on existing variations
2) evolution is limited by historical constraints
3) adaptations are often compromises
4) chance, natural selection and the environment all interact
82
Explain why selection can only act on existing variations
Natural selection favours only the fittest variations from those which are available
These may not be ideal traits
New and advantageous alleles can not be created on demand
83
Explain why evolution is limited by historical constraints
Evolution operates on the traits that an organism already has
It does not produce new structures
It modifies existing structures to adapt them to new situations
Ex movement of land animals to water
84
Explain why adaptions are often compromises
Each organism must be able to do many different things
| Ex ducks must be able to swim and fly
85
Explain why chance natural selection and the environment all interact
Chance effects the genetic structure of a population to a large extent
Not all alleles fixed by genetic drift in a gene pool of a small population are better suited to the environment then the alleles which are lost
86
Define a species
A group of organisms that are able to breed with one another and produce fertile offspring
A species will not be able to produce fertile offspring with members of other groups
87
Define speciation
The emergence of new species
88
Define macro evolution
Broad patterns of evolutionary change over long time periods
Large scale changes that include the introduction of new groups
Major changes recorded in the history of life over large periods of time
89
How does speciation act to increase the diversity of life
Usually a new species closely resembles its parent species (miroevolution) by occasionally a new species will have enough change to define a new branch on the tree of life (macro evolution)
90
Charles Linnaeus developed the taxonomic system of naming and classifying how does it work
A binomial system assigning a genus and a species name to each organism
Organisms were grouped as species based on physical similarities
91
What is the biological species concept
Defines a species as a group of populations whose members are able to interbreed and produce fertile offspring
Members of different species do not usually mate with one another but if they do their offspring are usually infertile
92
Define reproductive isolation
Occurs when the inability to produce fertile offspring assists in maintaining the gap in between different species
Prevents gene flow between populations of different species
93
What are some problems with the biological species concept
Prokaryotes do not reproduce sexually
| We are unable to determine whether fossils were capable of interbreeding
94
What are other ways to define a species
1) morphological species concept
2) ecological species concept
3) phylogenetic species concept
95
Explain the morphological species concept
Classification of a species based on measurable and observable physical traits
Ie) size shape and other features
Doesn't require information on interbreeding
Disadvantages is relies on subjective criteria
96
Explain the ecological species concept
Identifies species on the basis of ecological niches
How they have adapted to a particular environment
Ie) two fish may be similar but distinguishable based on diet or depth of where they live
97
Explain the phylogenetic species concept
Defined as the smallest group of individuals that share a common ancestor and form one branch on the tree of life
Determined based on comparisons of morphology and DNA sequences
Problem- agreeing on the amount of difference necessary to constitute a separate species
98
Define reproductive barriers
Features of a particular organism that makes it incapable of breeding with closely related species which live in the same geographical area
99
What are the two groups of reproductive barriers
1) pre-zygotic reproductive barriers
- prevent mating or fertilization between species
2) post-zygotic reproductive barriers
- operate after hybrid zones are formed
100
What are the five main types of pre-zygotic barriers
1) Temporal isolation
2) habitat isolation
3) behavioural isolation
4) mechanical isolation
5) gametic isolation
101
Explain temporal isolation
Occurs because two species mate at different times
Can be different seasons different years or different times of the day
Ex) some flowering plant have flowers which open at different times of day
102
Explain habitat isolation
Two species living in the same general location
Affects parasites that are animal host species
Ex) two snakes living in western North America but one lives on land and the other in water
103
Explain behavioural isolation
Little or no sexual attraction in between males and females of different species
Special signals that work to attract mates of the same species do not work with other species
Ex) courtship rituals are elaborate displays that must be performed before mating can occur
104
Explain mechanical isolation
Female and male sex organs are not compatible
| Ex) spiralling of snail shells in different directions prevents mating
105
Explain gametic isolation
The sexual act of mating may occur but the male and female gametes will not unite to form a zygote
Ex) sea urchins release eggs and sperm into the sea but fertilization will occur only if species specific receptors are present on the egg and the sperm allowing them to attach to one another
106
What do hybrids result from
The union of gametes from two different species
107
What are the three main types of post zygotic barriers
1) reduced hybrid viability
2) reduced hybrid fertility
3) hybrid breakdown
108
Explain reduced hybrid viability
Most hybrid offspring do not survive
| Ex) salamanders may hybridized but most hybrids do not complete development and those that do are very frail
109
Explain reduced hybrid fertility
Hybrid offspring of two different species reach maturity and are healthy but sterile
They are unable to facilitate gene flow between the two parent species
Ex) a horse and a donkey can mate and produce a mule, but the mule is sterile
The gene loop of the Hourie and the donkey remain separate
110
Explain the hybrid breakdown
First generation hybrid offspring are viable and fertile
When these hybrid mate with one another or with a member of one of the parent species the offspring are feeble or sterile
111
What are two mechanisms of speciation
1) allopatric speciation
| 2) sympatric speciation
112
Explain allopatric speciation
Speciation that occurs as the result of introducing a geographical barrier
Leads to the separation of a population with its gene pool from other populations of the same species
113
Allopatric speciation can occur as the result of
The introduction of a mountain range which gradually splits two populations of organisms
The formation of a land bridge diving marine populations in two
114
The size of the barrier required to create allopatric speciation depends on what
The species
Birds are not affected by the introduction of mountains or rivers
This likelihood of this occurring is higher when the population is small and isolated
115
Explain sympatric speciation
A new species arises within the same geographical area as the parent species
116
How can sympatric speciation lead to reproductive isolation if the populations are not separated from one another
Three main ways
1) polyploidy
2) habitat differentiation
3) sexual selection
117
Explain polyploidy
Accidents during cell division result in extra sets of chromosomes
A cell that has greater then two complete chromosome sets
Ex) a tetraploid plant arises from a diploid plant and can not produce fertile offspring
Most polyploidy species result from mating of two different species
118
Explain habitat differentiation
More likely to be the mechanism of speciation in animals
Adaptations to different habitats in the same geographical area can lead to speciation because mating in between the two groups would become rare
119
Explain sexual selection
Choosing mates based on some physical characteristics such as a colour
Leads to reproductive isolation via separated gene pools
120
Define hybrid zones
Regions in which members of different species meet and mate producing some hybrid offspring
These zones are studied by scientists to answer questions
121
When two separated but closely related populations come back into contact with one another do reproductive barriers remain or will the two species be able to interbreed and become one
This is answered by hybrid zones and there are three outcomes for the hybrid zones
1) reinforcements
2) fusion
3) stability
122
Explain reinforcement
When hybrids are less fit then both parent species
Expect that natural selection would strengthen/reinforce reproductive barriers
Prevents the formation of unfit hybrids
123
Explain fusion
Reproductive barriers between two species are not strong
Gene flow may occur in the hybrid zone reversing speciation
Two hybridizing species fuse into one
124
Explain stability
Hybrid zones are stable
Hybrids continue to be reproduced
Some gene flow may occur between populations
Each species maintains its own integrity
125
Define adaptive radiation
Is the evolution of many diverse species from one common ancestor
The adaptations of these species allow them to fill new habitats or roles in their community
126
When does adaptive radiation occur
When a few organisms colonize new unexploited areas or when environmental changes cause a number of extinctions opening up a number of habitats for new species
127
Define punctuated equilibrium
Long periods occurring with little or no change, equilibrium punctuated by abrupt episodes of speciation
128
Define the gradualism model
Species that have diverged gradually over long periods of time
Differences gradually evolve in a population as they become better adapted to their new environment
New species evolve gradually from the ancestral population
129
How old is the earth and how was the universe present
4.6 billion years old
| All matter was one big mass
130
What were the conditions on early earth
Earth probably began as a molten mass
The atmosphere was likely thick with water vapour and contained compounds from volcanic eruptions
As the earth cooler then the water vapour condensed into oceans
Very intense ultraviolet light lightning and volcanic activity
Lacked oxygen
131
What is the earliest evidence of life on earth
From fossils such as stromatolites which are 3.5 billion years old
And thought life may have arose 3.9 billion years ago
132
How did life arise
Scientists have collected evidence and did experiments that led to the hypothesis that the conditions of early earth could have allowed the production of simple cells
133
What are the four stages that simple cells could have formed
1) abiotic synthesis of small organic molecules such as amino acids and nucleotides
2) joining of these small molecules into macromolecules
3) packaging of these macromolecules into protobionts which are droplets surrounded by membranes that maintain an internal chemistry
4) the origin of self-replicating molecules which eventually made inheritance possible
134
Explain Stanley millers experiment findings
Miller was the first to show that amino acids and other organic molecules could be formed under the conditions of early Earth
Organic molecules cannot be synthesized spontaneously because of the presence of atmospheric oxygen
The energy comes through lighting and intense UV rays
135
Explain how Stanley miller experimented
A flask of warm water= early sea
Was heated so some would evaporate and move to the next flask
The second flask represented the atmosphere
Atmosphere consisted of hydrogen water vapour methane
Used electrodes to simulate lightening
Eventually he found organic compounds in the solution including amino acids
136
What is the geological record
Based on the sequence of fossils found within rock strata and the ages of rocks and fossils
137
The three eons of earth is what
Archean
Proterozoic
Phanerozoic
138
Which is the most recent eon and what are the three eras of that eon
```
Phanerozoic
1) Paleozoic
2) Mesozoic
3) Cenozoic
These are further divided into periods
```
139
What was the world like in the Paleozoic era
All life was aquatic
140
What was the world like in the Mesozoic era
The age of the reptile
Or dinosaur era
Beginning of mammals and flowers
Everything but birds went extinct
141
What was the world like in the Cenozoic era
Explosive evolution of mammals birds and angiosperm plants
| Most recent era further subdivided into epochs
142
What was the continental drift
German meteorologist wegener proposed that the earth began as one great mass which broke up into continents that then drifted into their current positions
Slow and continuous movement of earths crystal plates
Important geological processes occur at plate boundaries such as earthquakes
143
Define Pangea
Means all land and is the term assigned to the supercontinent
Brought species back to compete with each other
Lowered sea level killing marine organisms
Reshape biological diversity
144
How did the Pangea break up
Led to modern Arrangements of continents
Eurasia and India collision created the himalaya's
Lungfish got a unique pattern from this Pangea
145
Reasons for extinction may occur
```
Destruction of habitat
Unfavourable climate changes
Changes in the biological community
---introduction of predators
---introduction of competitors
```
146
How many mass extinctions have there been over the past 500 million years
5
147
Define phylogeny
The history of a species or a group of species
148
Define homologous structures
May look and function differently in different species but they exhibit fundamental similarities because they evolved from the same structure in a common ancestor
149
Define convergent evolution
Species from different evolutionary branches may come to resemble one another if they live in similar environments and natural selection acts to favour the same adaptions
150
Define analogy
The similarity due to convergent evolution
Ex) two organisms that have small paws small eyes protection on there nose
Are not homologous but rather analogous
151
Define systematics
A biological discipline focuses on classifying organisms and determining their evolutionary relationships
152
What are the major groups of classification
```
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
```
153
Define a clade
A group of species that includes its ancestral species and all of its descendants
154
Define a monophyletic
An inclusive group of ancestors and decadents
155
Define shared derived characters
These are new traits which develop in an organism and is passed on to its descendants
156
Define shared ancestral characters
These are the original traits present in the ancestral groups
157
Define cladograms
Compare an in group and an out group
158
Define in group
This is the group of taxa that is actually being analyzed
159
Define out group
This is a species or a group of species that is known to have diverged before the lineage that contains the groups to be studied
160
Define molecular systematics
Molecular systematics is the comparing of nucleic acids or other molecules to look for relatedness
161
What does DNA do
Encodes rRNA that is useful to investigate relationships that diverged hundreds of millions of years ago (slowly)
DNA of the mitochondria reveals more recent evolutionary events (rapidly)
162
What are the 5 kingdom system from the 1960's
| What was changed and used today as the three kingdom system
```
Monera
Protista
Plantae
Fungi
Animalia
Changed
Bacteria
Archaea
Eukarya
```
163
Describe prokaryotes
```
Very small
Very numerous
Tolerate extreme environments such as acidic basic salty hot and cold
Bacteria can cause human diseases
Many bacterias are beneficial for humans
```
164
What is the current hypothesis of archaea and eukaryotes
Evolved from a common ancestor
165
What are differences between bacteria and archaea
Bacteria has peptidoglycan and archaea does not
166
What are the shapes of prokaryotes
```
Cocci = spherical shape
• staphylococci grape clusters
• streptococci chains of circles
Bacilli = rod shape usually single
• diplobacilli two rods
• streptobacilli rods in a chain
Spiral = helical shape
• spirilla short
• spirochete long
```
167
Bacterial cell wall
Composed of sugar (peptidoglycan)
| Maintains shape and provides protection and prevents cell from bursting in hypotonic environments
168
What are the two main types of bacterial cell walls
Gram positive = thick layer of peptidoglycan
| Gram negative = thin layer of peptidoglycan with an outer membrane
169
Describe the gram stain
```
Purple = gram positive
Pink = gram negative
```
170
Explain the capsule of the bacterial structure
A sticky layer of polysaccharide or protein covering the cell wall
Not found in all prokaryotes
Allows bacteria to adhere
Acts as a shield to the microorganism from host defences
171
Bacterial Pili
Hair like appendage
Allows bacterium to adhere to one another or their substrate
Allows adherence to rocks in streams or the lining of human intestine
Specialized pili called sex pili allow bacteria to stick to one another and transfer DNA
172
Bacterial flagella
This structure enables bacterial motility
Not present in all bacteria
Flagellated bacteria may have one flagella two flagella or many
Allows the bacteria to move towards chemical and light stimuli called attractants and away from repellent stimuli
173
Bacterial reproduction
Replication occurs very quickly by a process called binary fission
Sometimes species can reproduce in as little as 20 mins others take 1-3 hours
Growth is limited because nutrients become exhausted competition and antibiotics
174
Bacterial endoscopes
Structure formed by some gram positive organisms only
Used to withstand harsh conditions
Outer cell will disintegrate and the inner cell with remain
Endospores has a thick outer coat
Will dehydrate and become dormant
Can withstand extreme heat and cold
175
Bacterial internal membranes and internal structures
Prokaryotes have a much simpler internal structure and genome then eukaryotes
Have specialized membranes to preform metabolic functions
Have plasmids = smaller pieces of DNA
176
What are the two main metabolic resources of prokaryotes
A source of energy
| A source of carbon
177
Explain the source of energy of prokaryotes
Can either use light or chemicals
1) light = phototroph
2) chemicals = chemotroph
178
Explain the source of carbon of prokaryotes
Make their own carbon compounds or others require pre formed carbon
1) autotrophs = use an inorganic carbon dioxide such as glucose called photosynthesis
2) heterotrophs = obtain their carbon from organic compounds such as glucose
179
If they use light as their energy source and CO2 as their carbon source what are they
Photoautotrophs
180
If they use chemicals for energy and CO2 for a carbon source what are they called
Chemoautotrophs
181
If they use light as their energy source and organic compounds as a carbon source what are they called
Photo heterotrophs
182
If they use chemicals as their energy source and organic compounds as their carbon source what are they called
Chemo heterotrophs
183
Define biofilms
Surface-coating colonies
Consist of a single species of bacteria or many different species
When the colonies are big enough they begin to produce proteins that cause them to stick to a particular surface and to each other
184
What do humans use biofilms
Allow bacteria to adhere to teeth causing dental carries
Form on catheters and other medical devices
Beneficial when used in water sewage treatment facilities
185
Why can archaea live in such extreme conditions
Have unusual proteins and other molecular adaptions that allow them to survive and reproduce
186
What are the three main groups of archaea
1) extreme Halophiles (salt)
2) extreme Thermophiles (temp)
3) methanogens (intestinal tract of swaps)
187
What are some of the groups of bacteria
1) proteobacteria
2) chlamydias (live in cells)
3) spirochetes (pathogens)
4) gram positive (strep)
5) Cyanobacteria (oxygen)
188
What are the 3 subgroups of Proteobacteria
```
Alpha = Rhizobium
Gamma = salmonella etc
Delta = attack other bacteria
```
189
What are the two classes of bacterial toxins
```
Exotoxins
- secreted by bacterial cell into environment ie toxic shock
Endotoxins
- gram negative outer membrane
Ie fevers aches
```
190
Define bioremediation
This is the use of organisms to remove pollutants from the soil water or air
