Ap Bio

Indianna Amaro

November 2015

Ap Biology

HW 1-5

Homework #1

1.D

2.B

3.B

4. 1.5 meters

5. B

Homework #2

        (a)The most appropriate sample of rocks in which to search for a transitional species between lobe-finned fishes and amphibians is sample 2, which is 370 million years. This would be the most appropriate sample of rocks because it is right in between the lobe-finned fishes which are 380 million years and the amphibians which are 363 million years. Therefore sample 2 is right in between which can show us the transition of the two species. (b)One piece of evidence that would support the hypothesis that amphibians evolved from lobe-finned fishes is the structure. Both species have similar body structure and they have similar organelles, which can help determine whether the amphibians evolved from the lobe-finned fishes. Another piece of evidence that would support the hypothesis is the location in which the fossils were found, because if they were found near each other then this can show that they might have had a common ancestor.

Homework #3

         (a)One piece of evidence that would indicate new genetic variation has occurred in the engineered flies is different DNA sequence. (b)One mechanism that can lead to genetic variation is sexual reproduction that produces new traits. (c)Genetic variation in a population contributes to the process of evolution in the population. Evolution is the process by which different kinds of living organisms are thought to have developed and diversified from earlier forms. With genetic variation certain traits will be selected to make individuals adapt better to their environment. A population will slowly begin to evolve with genetic variation.

Homework #4

        (a)Through the process of mitosis a cell can reproduce asexually. In this process, chromosomes are replicated. They are replicated by the chromosomes moving through the opposite ends of the cell, leading to cell separation. The evolutionary advantages of asexual reproduction include a more advantageous way of multiplying because the process of finding a mate is not necessary. (b)Sexual reproduction increases genetic variation because it allows two organisms to mate with different traits, being able to reproduce an offspring with a variety of different traits. Allowing the offspring to mate and reproduce an offspring of its own with different traits. Moreover, if an animal immigrates into a population and breeds with another animal of the population it is also able to reproduce and offspring with different traits as long as it can sexually reproduce. (c)A prezygotic is a mechanism that does not allow two organisms to produce an offspring even with the act of mating.