ecology quiz 3 :o Flashcards
10.2 Genetic variation among individuals in a population arises from shuffling in ____ & ____ in sexual reproduction
genes & chromosomes
10.2 In sexual reproduction, between the 2 diploid individuals, they produce haploid ____ which is _____, and they combine to form a _____ called a ____ and it has a full _____.
gametes, sperm and egg, diploid, zygote
10.2 What is the major source of genetic variability?
Recombination
10.2 Which reproduction does not involve the fusion of gametes?
Asexual reproduction
10.2 Define Parthenogenesis
development of individual from egg that did not undergo fertilization
10.2 Asexual reproduction can result in what? And at what cost?
High population growth & the cost in loss of genetic recombination
10.2 Low genetic variability among individuals in a population means…
the population responds uniformly to changes in the environment
10.2 Mixing of ____ and ____ that occurs in sexual reproduction produces genetic variability
genes & chromosomes
10.2 (T/F) Sexual reproduction produces a broaded range of responses to environment
True
10.2 (T/F) Sexual reproduction decreases probability of individuals surviving environment changes
false - increase
10.2 Which reproduction is more energetically costly and why?
Sexual reproduction because production of gametes, courtship activities, and mating are energetically expensive
10.2 (T/F) Eggs are larger and energetically more expensive than sperm
True
10.3 Two individuals produce a haploid gamete that combine to form a _____
Diploid cell
10.3 Define dioecous
Having male and female reductive organs on separate plants
10.3 Organisms who possess both female and male parts are?
Hermaphrodites
10.3 In plants, they are hermaphroditic by? And termed?
Possessing bisexual flowers with both male (stamens) and female organs (ovaries)
Perfect
10.3 Define monoecious
Having male and female reproductive organs separated on the same plant (termed imperfect)
10.3 Single self-fertile ______ plant can colonize a new habitat, reproduce, and establish ____.
hermaphroditic
new population
10.3 Define simultaneous Hermaphrodite
Individual organisms that possess both male and female sex organs at the same time in its life cycle
10.3 Population of hermaphroditic individuals is able to produce twice as many offspring as _____.
population of unisexual indivudals
10.3 Define sequential hermaphrodites
Organisms that changes sex from female to male (vice versa) at some point in its life cycle
- Usually takes place as they mature/grow
10.3 (T/F) Plants can also undergo sex change
True
10.4 What activities can reduce the probability of future survival?
Aquisition of mate, defense of breeding territory, feeding and protection of young
10.4 (T/F) Reproduction directly reduces individuals ability to produce future offspring
True
10.4 Allocation to reproduction shown to..?
Reduce allocation to growth in plants/animals
10.4 Individuals reproducing ____ in age will produce ___ offspring per productive period than one who postpones reproduction in favor of additional growth.
earlier
fewer
11.2 As population density increases….
availability of resources declines
11.2 Define density dependence
regulation of population growth by a mechanism controlled by population size; effects increase as population size increases (its effects influence pop. in proportion to its size)
11.2 Density dependence functions to SLOW rate of population growth with increasing population density by….
Increasing rate of mortality, decrease rate of fecundity, or both
11.2 Define density-dependent mortality
Increase in mortality(death) rate with increasing population size
11.2 Define density-dependent fecundity
Decline in fecundity(birth) rate with increasing population size
11.2 (T/F) Population density can influence patterns of predation/spread of disease and parasites
True
11.2 Define density independence
being unaffected by population density; regulation of growth is not tied to population density
11.3 Competition occurs when…
individuals use a common resource that is in short supply to the number seeking it
11.3 Define intraspecific competition
competition among individuals of the same species
11.3 (T/F) As long as availability of resources does impede the ability of individuals to grow, survive, and reproduce… no competition occurs
False - does NOT
11.3 Define scramble competition
Limited resources are shared to the point that no individual survives
11.3 Scramble competition occurs when?
When growth and reproduction are depressed equally across individuals in a population as intensity of competition increase
11.3 What can scramble competition lead to?
All individuals receiving insufficient resources for survival and reproduction - resulting in local extinction
11.3 Define contest competition
limited resources shared only by dominant individuals
11.3 Contest competition takes place when?
When some individuals claim enough resources while denying others a share - only a fraction of population suffers aka unsuccessful individuals
11.3 (T/F) Competing individuals may not directly interact with one another
True
11.3 Define exploitation
Indirect interaction as they compete for resources
ex) use of resources by one individual = decreases amount available for others
11.3 (T/F) Competing individuals may directly interact
True
11.3 Define interference
Direct interactions of organism fighting for resources
ex) preventing others from occupying a habitat/ accessing resource within in
11.4 Intraspecific Competition is usually…
Density dependent, it increases gradually and first affects growth/development - later it affects survival/reproduction
11.4 What happens as population density increases to a point where resources are insufficient to provide for all?
Some or all individuals reduce their intake of resources & reduction slows rate of growth and development
11.4 Define density-dependent growth
Inverse relationship between population density and individual growth
11.5 Competition for resources at high population densities can…
Function to reduce survival
11.5 Mortality function to increase per capita resource availability, allowing for?
Increased growth of surviving individuals
11.5 Link between density-dependent mortality, resource availability, and growth rate is apparent in organisms that exhibit…
Indeterminate growth rates that respond strongly to resource availability, such as plants!
