Daphnia is a micro-organism that is hunted by other microorganisms. It has the ability to alternate between asexual and sexual reproduction depending on the population density and environmental conditions. If the competition for resources is high, it sexually reproduces; otherwise, it reproduces asexually. Discuss how this ability to switch its reproductive strategy is beneficial when:

a)The population is small.

b)When the population is large, and resources are limited (dependable environment)

c)How could heavy predation affect the population? Think in terms of density and reproductive strategy.

d)Do you think they would be iteroparous or semelparous and why? Semelparous—small and short life span, high predation, no parental care, high number of offspring, type III survivorship.

step 1: initiation

initiation is the beginning of transcription. it occurs when the enzyme rna polymerase binds to a region of a gene called the promoter. this signals the dna to unwind so the enzyme can ‘‘read’’ the bases in one of the dna strands. the enzyme is now ready to make a strand of mrna with a complementary sequence of bases.

step 2: elongation

elongation is the addition of nucleotides to the mrna strand. rna polymerase reads the unwound dna strand and builds the mrna molecule, using complementary base pairs. there is a brief time during this process when the newly formed rna is bound to the unwound dna. during this process, an adenine (a) in the dna binds to an uracil (u) in the rna.

step 3: termination

termination is the ending of transcription, and occurs when rna polymerase crosses a stop (termination) sequence in the gene. the mrna strand is complete, and it detaches from dna.

if the hares very faster than they are now, and thus the lynx's hunting success rate drops because it will be harder to catch them, the rate that will change will be the pray-rate. the pray-rate will change because more hares will be able to survive, thus more individuals for reproduction, so the end result will be increasing population of hares.

the predator-rate will remain pretty much the same because there will be more than enough pray, but the hunting success rate is stagnant.