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Biology 121 Final Exam > Exam 3 Content > Flashcards

Exam 3 Content Flashcards

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1
Q

what is a population?

A

interbreeding group of organisms of the same species in the same area

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2
Q

what is Exponential growth?

A

Unrestricted growth, which rate depends on the number of individuals in the population
All populations can do this but cannot be maintained due to resource limitations

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3
Q

how is discrete exponential growth calculated?

A

N = NoRo^t
Ro = net reproductive rate
Number of females produced per current female
No = initial population size
N = population size
T = time

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4
Q

in what population/breeders do discrete exponential growth occur?

A

Non-overlapping breeders
Discrete breeders
Ex) Moth breeds once and dies
Ro = 1.9 No = 600
N = (600)(1.9)^2
N = 2166

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5
Q

what is Continuous exponential growth?

A

Breeding can go on all the time
Has overlap of generations

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6
Q

how is continuous exponential growth calculated?

A

ΔN/Δt = (rate)N
Δ = number of individuals per unit time
N = number of individuals
r = intrinsic rate of increase
N = Noe^rt
Ex) Head lice
r = 0.028/day
N = 1000 adult life
ΔN/Δt = (0.028)(1000) = 28/day
N = Noe^rt
N = 1000e^(.028)(5)

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7
Q

when should each formula for exponential growth be used?

A

N = NoRo^t predicts population size (non-overlapping)
ΔN/Δt = rate predicts growth rate (overlapping)
N = Noe^rt predicts population size (overlapping)

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8
Q

what is Logistic Growth?

A

Restricted growth

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9
Q

How is logistic growth calculated?

A

Carrying capacity of the environment (K)
Max population size
Population size vs time → S-shaped curve
ΔN/Δt = rN(K-N/K)
Example: Population size is low
K-N^r0/K → K/K
Example: Population size is average
N = K
K-N/K = 0 → ΔN/Δt = 0
No growth

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10
Q

what is Population Regulation?

A

this limits population growth

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11
Q

what are Density Independent Factors?

A

Not influenced by population size
Individual population size does not matter
abiotic factors

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12
Q

what are abiotic factors?

A

examples:
Climate
Fire
Floods
Hurricanes
Tornadoes

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13
Q

what are Density Dependent Factors?

A

The effect depends on population size
Instenifive as population size increase
Prediction
Disease
Competition
Crowding stress

Newly introduced species can increase population size rapidly when in the new environment there is no predators, competition, and parasites

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14
Q

what is Demography?

A

Study of vital statistics that affect population growth

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15
Q

how is demography calculated/measured?

A

Nfuture = No + B - D + I - E
No = current
B = birth rate
D = death rate
I = immigration rate
E = emigration rate

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16
Q

what is Survivorship?

A

Primary measure for assessing population dynamics
Mirror image of mortality
Assess it by lx
Proportion of original cohort (individuals produced at the same time) surviving to age x

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17
Q

when does survivorship vary?

A
  1. Among species
    Humans survive longer than dogs
  2. Between sexes in a species
    Females live longer than males
  3. Environmental conditions
    Developed vs developing countries
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18
Q

what is a Type 1 Survivorship curve?

A

occurs in K-selected organisms
Low mortality until old age
Produce few offspring
Examples: Elephants, humans (developed countries), rotifers, etc.

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19
Q

what is a type 2 survivorship curve?

A

Constant mortality throughout life
Examples: Lizards, songbirds, seagulls, etc.

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20
Q

what is a Type 3 Survivorship curve?

A

occurs in r-selected organisms
High juvenile mortality
Few survive to adulthood
Examples: Insects, oysters, etc

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21
Q

what is Fecundity?

A

an organism’s reproductive capacity

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22
Q

what is age-specific fecundity and how is it measured?

A

Age-specific fecundity = mx = # of daughters/female at age x
The highest birth rate in humans is 20
Only measure females because females determine the population size

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23
Q

what is a life table?

A

Summarize populations demographic parameter
Calculate Ro = net reproductive rate
Ro = Σlxmx

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24
Q

what is age distribution?

A

Graphical representation of the proportion of the population at each age class
Can influence population growth
Can tell you if the population is growing or not growing
The female side is always fatter than the male side because females live longer

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25
what are Life History Strategies?
All the characteristics that affect survival and reproduction Natural selections should produce organisms that produce the highest r (intrinsic rate of increase) Copies of your genes make it to the next gene pool Depends on the environmental conditions
26
what is r-Selected Strategy?
Opportunistic life history Form a continuum Geared towards rapid life cycle completion in an unpredictable environment Tramps → high r value Reproduce early and often Density independent Exploit resources rapidly and disperse offspring everyone Even if it costs them their life
27
what is a K-selected strategy?
Equilibrial life history Competing for resources in a stable environment Population size in near carrying capacity (K) Quality not quantity of kids Few, well provisioned kids Density dependent Lots of other oransgism like them Compete Take care of their young to compete among others Climax forest
28
what are the parameters of r-selected strategy?
Survivorship Curve - Type 3 Life Span - Short # of offspring - High # of lifetime reproductive events - Once (semelparous) Environment - Variable General strategy - Productivity
29
what are the parameters of K-selected strategy?
# of offspring - few Survivorship Curve - Type 1 and 2 Life Span - Long # of lifetime reproductive events - Several (iteroparous) Environment - Stable General strategy - Efficiency
30
what is Demographic transition?
A demographic device that explains the relationship between population growth and development
31
Why doesn’t birth rate drop as fast as death rate?
Historical view - that you need lots of children Labor on a farm Desire to increase your numbers compared to other countries or tribes Many children = prestige (for males) Lack of birth control (availability or knowledge)
32
what are the 7 challenges of human population growth?
1. Agricultural productivity Uneven food distribution 2. Dependency on non-renewable resources (fossil fuels) Increases CO2 in the atmosphere) 3. Loss of biodiversity The rate of deforestation is very high Species are disappearing rapidly 4. Accumulation of pollutants 9 million premature deaths attribute to this 5. Water stress 1.2 billion people experience water stress Water scarcity 6. Desertification Good soil is limited and we are losing it Takes away cropland 7. Climate change The greatest impact on people who are least responsible for it Most vulnerable to health issues
33
Ecological interactions with species A and B?
Competition - - Predation + - Parasitism + - Mutualism + + Comencilism + O Amentulism - O
34
which ecological interactions are often clustered under the term symbiosis?
Parasitism, Mutualism, and Comencilism
35
what is a Niche?
range of abiotic and biotic conditions in which an organism can survive and reproduce (conditions they can live in)
36
what is a fundamental niche?
all the resources an organism can theoretically use (can use all of these resources if there are no other organisms around)
37
what is a realized niche?
portion of the fundamental niche that is actually utilized
38
what is the Competitive exclusion principle?
Limit to the amount of niche overlap that will allow 2 species to coexist → niches cannot be identical
39
what is competition?
Competition is when you have 2 or more organisms that use the same resources that are limited or in short supply (Mutually negative effect)
40
what is the difference between interspecific and intraspecific?
Interspecific → among species Intraspecific → within species
41
what is Exploitation Competition?
when you try to obtain and use resources before your competitors
42
what is interference competition?
when you actively prevent the competitors from obtaining the resources Example: Plants use toxins for interference competition
43
what is competitive exclusion and an example of this?
one species becomes locally extinct The winning population reaches a sufficient density that it uses all the resources under the conditions in that area European starlings: 100 were introduced into the central park in 1891 Compete with blue birds
44
what is context-dependent?
Either species win depending on the conditions Competitive abilities are relative Depend on a particular set of adaptations
45
how is the stable coexistence of 2 competitors maintained?
by resource partitioning and character displacement
46
what is a lab experiment of Resource Partitioning?
Warblers - MacArthur Small insect eating birds that live in trees 5 species - sympatric - seemed to use the same niche (trees) They had slightly different feeding habits in the spruce trees Niche differentiation Guilds - group of species that exploit the same resource in slightly different ways
47
what happened in Paramecium - Gause experiment?
2 closely related species to Paramecium: P. aurelia and P. caudatum When they were grown alone they went to their K (logistic growth) When they were grown together they compete (negative impact on both) P. aurelia drives P. caudatum to extinction in the jars
48
what happened in Flour Beetles (Tribolium) - Park experiment?
Park found that there was a shift in competition depending on the temperature in the jars that he used A shift in competition depending on the environment T. castabeum wins when its hot and moisty T. confusum wins when its cool and dry
49
what is Character displacement?
niches differ whether they are sympatric or allopatric Allopatric populations are alike Sympatric populations differ Minimizes competition
50
what is Mutualism?
a type of symbiotic relationship where all species involved benefit from their interactions.
51
what is Aposematic coloration and an example of this?
warning coloration Yellow jacket, skunk
52
what are the 2 types of mimicry?
1. Batesian mimicry: when a harmless species mimics a deadlier one EX: King snakes mimic coral snakes Mimicry of a distasteful species by a species that is not distasteful 2. Mullerian mimicry: when 2 distasteful species mimic each other
53
what is cryptic coloration?
some prey items use camofaudge Ex: Peppered moths
54
what is Early detection?
moths that are hunted by bats have very sensitive ears that are tuned to the frequency of the bat
55
what is Indictable defense?
a defense produced by predator pressure Ex: Clams or mussels - thicker shells when predators, like crabs, are common
56
what is a Keystone predator?
a predator in which increases diversity in the system
57
what is Coevolution?
The sequence of evolutionary events in which 2 interacting species modify their interaction - Only occurs when interactions affect both species (predation, competition, mutualism, parasitism)
58
what is AMR - Antimicrobial Resistance?
when the pathogens change
59
what are Plasmids?
DNA circles that are easily exchanged (horizontal gene transfer)
60
what is a MCR -1 gene?
mobilized colistin resistance gene Travels in plasmids causing resistance to colistin Each year 30,000 die in the US die due to AMR 1.2 million deaths (2019)
61
what is Myxomatosis?
rabbit plague is a viral disease that occurs mainly in domestic and wild rabbits
62
what does Virulent mean?
kill host too quickly low transmission
63
what does Acirulent mean?
did not cause open sores low transmission
64
what does intermediate virulence mean?
high transmission
65
what are parasites?
A parasite is an organism of one species that obtain nutrients from a host, and typically does not kill the host right away +/- (antagonistic interaction)
66
what are Ectoparasites?
things like mosquitos, ticks, and lice
67
what are Endoparasites?
things like tapeworms, etc.
68
what is Hookworm disease?
affects about 1.3 billion A small, roundworm that is in the blood system that sucks blood from inside
69
what is Schistosomiasis?
affects about 230 million - trematode (flatworm)
70
what is Malaria (Plasmodium)?
typically about 600,000 die of Malaria each year - Anemia - Chills and fever
71
what is Ascaris?
1.5 billion affected - The large roundworms that live in the intestines - Malnutrition and parasites are responsible for about 20% of the deaths on earth (12 million)
72
what is the Vertebrate Immune system?
reacts to non-self (antigens that are not your antigens) Sometimes not effective due to parasitic adaptations Counter adaptations
73
what is the SIR model ?
Susceptible, Infected, Recovered (Immune)
74
what is Schstioma mansoni?
blood fluke/flatworm that causes a chronic disease called schistosomiasis
75
what are vectors?
Vectors are agents that transmit a disease
76
what is Behavior modification?
Infection that causes a change in intermediate host behavior Increases chance of transmission of the parasite (parasites can affect the behavior of one host they are in, in order to get to the next host) Can make a host more susceptible to predation so that they can get to the next host (the next host will eat the current host) This leads to temporal and spatial overlap of the next host
77
what is Latency/reduced virulence?
Virulence - the ability to pass pathogenic effects Selection to avoid killing host too soon (myxoma virus)
78
what is Mimicry in parasites?
Example: Schistosome adult worms Mask themselves with host antigens Take antigens from your blood system and wear them (like a cloaking device)
79
what is Hit and run in parasites?
Stimulate the immune system in one part of the body and then move to a safe space away from the immune system The immune system does not work in your intestines
80
what is live in the immune system in parasites?
Toxoplasma - macrophages (defensive cells) Mycobacterium Tuberculosis - a bacteria that is eaten by macrophages Bacteria cant reproduce and the immune system doesn't kill it, but halts TB replication Latent TB standoff between host and parasite Over 10 million new cases of TB in 2021 Of these cases, 1.6 million died of TB
81
what is Antigenic variation?
Trypanosomes Blood protostomes They change their surface antigens at regular intervals Parasites have a VSG - variant surface glycoprotein (covers the parasite) The immune system sees VSG and then makes antibiotics to VSG1 Express different genes at different times to deal with the immune system and to get ahead of the immune system
82
what is HIV?
HIV - Human Immunodeficiency Virus
83
what is a Retrovirus?
doesn't live well outside of the cell Most complex lifecycle
84
what is the life cycle of retrovirus?
1. Retrovirus passes RNA into the host cell 2. The enzyme reverse transcriptase catalyzes the formation of DNA from RNA 3. The DNA copy enters the nucleus and inserts into a chromosome 4. Transcription of viral genes to RNA by host enzymes 5. Production of viral proteins via translation
85
what are T helper cells?
type of immune cell
86
what is AIDS?
Acquired Immunodeficiency Syndrome (acquired by HIV)
87
what does the destruction of T helper cells do?
The destruction of T helper cells (CD4 cells) will suppress the immune system, eventually destroying the immune system
88
what are opportunistic infections (OI)?
They die from the fungi, bacteria, etc that are already inside the body, but when the immune system is destroyed by the disease, the immune system is no longer able to keep these in check, therefore causing them to get out of control and cause death These organisms are called opportunistic infections (OI) Infection kills patients because of the crippled immune system
89
what are Nucleotide RT inhibitor drugs?
(the first type of drug created) - functions early in the lifecycle binds/bonds/alters RT so that the virus can’t do RNA → DNA We found with this drug that the virus quickly developed resistance to these drugs because there are so many mutations that they were able to change
90
what is a Protease inhibitor drug?
attacks late in the life cycle Inhibits the enzyme that cuts HIV proteins to the right size
91
what are Fusion inhibitor drugs?
Fusion inhibitors (CCR5 antagonist) - happens very early in the life cycle Prevents HIV from entering cells
92
what are integrase inhibitor drugs?
Blocks viral enzyme that helps intergate/insert the virus DNA into our DNA/cell DNA
93
what is ART (anti-retroviral therapy)?
delaying the disease decreasing the death rate considerably Not a cure, but pretty effective in reducing the death rate
94
what is PrEP - Pre-exposure Prophylaxis?
Taken by uninfected people at high risk (HIV -, but at high risk for it) Truvada and Descovy
95
what are the Transmission categories of HIV/AIDS?
80% of AIDS patients in the US homosexual males (MSM) IV drug users Or both Heterosexual transmission → about 22% of cases in the US
96
how is HIV transmitted?
Transmit in semen, blood, and cervical secretions (not in saliva, tears, or urine) Unprotected Sex (either heterosexual or homosexual sex can cause HIV to be transmitted if one partner is infected) Exposure to Blood Birth (infected mothers can transmit it to their children)

Biology 121 Final Exam (3 decks)

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