What is the evidence that an asteroid collision has happen before?

List two new traits (structural or behavioral) that each new species of rat might demonstrate as it adapts to the conditions on two of the four islands. choose only two islands that are described in the lesson. record the island latter and the major habitat feature of the island. then list two new traits each rat subspecies might demonstrate in order to survive the habitat on that island. note: new traits should be unique to that island and be in response to that island’s habitat feature. i cannot remember islands that were names in the lesson so only answer if you have done the lesson (5.13 life science 7b) choose 2 of the islands and describe a structural and a behavioral trait for a rat on each island so 4 total answers, 2 different structurals and 2 different behaviorals, one for each rat for each island

Why does meiosis produce cells with half the chromosomes? o a. most of the chromosomes are not necessary to keep an organism alive. b. a gamete needs only half the number of chromosomes because two gametes join together. o c. it makes the gametes easier to move around in the organism. o d. it is faster to produce gametes with fewer chromosomes.

In 1959, doctors began using the powerful antibiotic methicillin to treat infections of staphylococcus aureus, but within two years, methicillin-resistant strains of s. aureus (mrsa) appeared. how did the resistant strains of s. aureus emerge? in 1959, doctors began using the powerful antibiotic methicillin to treat infections of staphylococcus aureus, but within two years, methicillin-resistant strains of s. aureus (mrsa) appeared. how did the resistant strains of s. aureus emerge? staphylococcus aureus bacteria that were able to synthesize cell walls using a protein that was not affected by methicillin survived the methicillin treatments and reproduced at higher rates than did other individuals. over time, these resistant individuals became increasingly common. in response to treatment of staphylococcus aureus infections with methicillin, some bacteria began to synthesize cell walls using a protein that was not affected by methicillin. these bacteria survived the methicillin treatments and reproduced at higher rates than did other individuals. over time, these resistant individuals became increasingly common. in response to treatment of staphylococcus aureus infections with methicillin, bacterial populations gradually began to synthesize cell walls using a protein that was not affected by methicillin.