Topic 10- Reproduction Flashcards
(27 cards)
what is Eproduction ?
the amount of energy available to an organism to be put towards growth of biomass or reproduction of offspring.
what are life history traits?
traits that maximize lifetime reproductive success (fitness)
what are the environmental factors that influence energy budgets?
amount of light, food sources, shelter, wind, precipitation, etc.
what is indeterminate growth? which organisms do we see it in?
indeterminate growth is growth that continues throughout the organisms entire life. Energy is constantly going towards growth. we see this in ectotherms.
what is determinate growth? which organisms do we see it in?
determinate growth is growth that ceases when an organism reaches “adult” state. Energy can go towards maintenance and reproduction. We see this in endotherms.
what is asexual reproduction?
production of clones. primarily used by prokaryotes, they replicate their genes and divide by binary fission. can also be used by eukaryotes dividing by mitosis.
what is sexual reproduction?
combined genomes. replicated genomes are half gametes (sperm or eggs) that are combined with other half gametes to produce zygotes. Only occurs in eukaryotes.
what is passive care?
pre”birth” energy investment such as seed development, gestation. these things happen automatically.
what is active care?
post “birth” energy investments, such as dispersing seeds, raising offspring.
what kind of growth do organisms with no active care follow?
indeterminate growth plans, after birth no energy is put towards raising offspring.
what is the trade off between number of offspring, parental care, and offspring survival?
when parents have a larger amount of offspring, less energy can be spent tending to each baby, so as number of offspring increase, offspring survival decreases.
what is the relationship between reproduction and parental survival?
the number of offspring determines how much energy the parent can put into themselves. as the number of offspring increases, the amount of energy spent on raising offspring increases, which decreases the amount of energy the parent can spend on themselves, decreasing parental survival rate.
what is semelparity?
individuals of the same species only have one reproductive episode in their lives.
what is iteroparity?
individuals of the same species can have multiple reproductive episodes in their lives.
if a human female only has one baby in her life is she semelparous?
no, the parity is based on the species not a choice, so although she chose to only have on child, humans are an iterparous species. parity is based on biology not choice.
does evolution favour larger animals?
fecundity increases with body size, with an advantage to delaying sexual maturity until later.
what are r-selective species?
they emphasize high growth rates and produce high amount of offspring in a semelparous parity. low parental investment and low survivorship of offspring.
what are K-selective species?
they posses relatively stable populations near carrying capacity. lots of energy into adult/offspring growth, low fecundity but iterparous parity. high junevile survivorship.
what are life history tables useful for managing?
crops/living stock
conservation efforts
pest/weed control
what does n(x) represent in a life history table?
the number of females at each age (x)
females followed because they reproduce
what does s(x) represent in a life history table?
the survival rate from one age to the next
s(x)= n(x+1)/ n(x)
what does l(x) represent in a life history table?
the survivorship
l(x)= n(x)/n0
what does m(x) represent in a life history table?
fecundity
what does R0 represent in a life history table?
the net reproductive rate
the avg. number of female offspring
