Bio 1520, Test 2
Rank the following mating systems from least to most selection for sperm competition. Polygyny Promiscuity True monogamy Social monogamy
Polygyny = True monogamy < Social monogamy < Promiscuity
What supports the development/maintenance of a polygynous system?
The females(s) aggregate for communal offspring care, and the male(s) exploit these groupings for reproductive pursuits.
Diplontic life cycles are characteristic of:
animals
One way embryonic cells can learn their position in an embryo is by detecting the concentration of a
morphogen
What conditions favors evolution of a polyandrous mating system?
offspring require a high degree of paternal care for survival
Reproduction from an unfertilized egg is called
Parthenogenesis
Gametes are produced by [blank] in the haplontic life cycle, by [blank] in the diplontic life cycle, and by [blank] in the alternation of generations life cycle.
mitosis; meiosis; mitosis
What is a cost experienced by an individual in a promiscuous mating system?
An individual experiences high risk of sexually transmitted diseases and parasites.
Which of the following is FALSE? A) Multicellularity allows organisms to become larger than physiologically possible for a single cell B) A cell can grow infinitely large as long as there is adequate nutrition in its extracellular environment C) In a multicellular organism, all cells must be exposed to either the environment or a circulatory system D) Adaptations that increase surface areas, such as invaginations or flattened cell shape, allow cells to become larger E) Development and cell specialization is a consequence of multicellularity
B) A cell can grow infinitely large as long as there is adequate nutrition in its extracellular environment
Which type of male competition would you typically expect in species with external fertilization?
Direct male competition( Male-male aggression or courtship displays) Indirect male competition (sperm competition)
Why are females more likely to be "choosy" about mating partners than males?
Females are more limited in the number of offspring they can produce than males are Eggs require more energy to produce than sperm Males can fertilize the eggs of multiple females, while a female's egg can only be fertilized by a single male
What is the selective advantage for a male to participate in a polyandrous mating system?
His offspring are unlikely to survive without his parental care.
What best demonstrates the relationships between the different developmental processes?
In the absence of induction, most of the other developmental processes would be severely impaired or not occur
As a cell gets larger, what happens to its surface area and volume?
Its volume grows more rapidly than its surface area.
Name some observations which support the "good genes" hypothesis to explain male/male competition and female choice.
The color and quality of male sage grouse air sacs, used in courtship displays, are extremely sensitive to parasitic infections Female widowbirds prefer males with the longest tails, but males with longer tails are more susceptible to predation Human males with symmetrical faces are considered more attractive than those with asymmetrical faces
Match the mating system to the parent that typically demonstrates the greatest parental investment in that mating system.
True monogamy - Equal investment from both parents Polygyny - Female parent Polyandry - Male parent Social monogamy - Equal investment from both parents, except in the case of extra-pair copulations
Rank the following mating systems from least to most selection for sexual dimorphism. Polygyny Promiscuity True monogamy Social monogamy
True monogamy = Promiscuity < Social monogamy < Polygyny
Monogamy is more likely to occur in
a species that lives in a habitat with very scattered resources
Spores are produced [blank] in the haplontic life cycle, [blank] in the diplontic life cycle, and [blank] in the alternation of generations life cycle.
by meiosis, are not produced; by meiosis
The mature, multicellular organism is [blank] in the haplontic life cycle, [blank] in the diplontic life cycle, and [blank] in the alternation of generations life cycle.
haploid; diploid; there is a haploid and a diploid at different stages
One way embryonic cells can identify where they are within in an embryo is by engaging in the process of
induction from adjacent cells
What is a cost to the female in a polygynous mating system?
little help from male in caring for offspring
In a species where females typically mate with multiple males...
males likely compete indirectly with each other through sperm competition for successful fertilization of a female's eggs males may have elaborate penis morphologies or large ejaculate volumes females may have the ability to preferentially use sperm from a specific male
Name some "costs" associated with sexual reproduction.
requires time/energy to find/court mate only females can produce offspring disruption of beneficial allele/trait combinations
In species that reproduce via external fertilization:
sperm and egg encounter each other outside of the female's body, typically in an aquatic environment
In species that are capable of both sexual and asexual reproduction, under what conditions is sexual reproduction more likely to occur?
when conditions for survival are unfavorable