Sperm whales have vestigial hip bones, and a small percentage of sperm whales also have vestigial hind limbs. Which of the following statements best explains the presence of these vestigial structures in sperm whales?
a. Sperm whales evolved from ancestors that walked on land.
b. Sperm whales are in the process of evolving into land mammals.
c. These structures are acquired by each individual sperm whale during its lifetime.
d. These structures resulted from sperm whales having a long period of embryonic development.

Zoe decided to measure the hand length of each of her classmates. first she marked a line across each student's wrist and lined up a ruler from this mark to the top of the middle finger to measure the length. then she recorded the measurements in the table below. marla did this the same way for each classmate, and then zoe used this ruler to measure each straight line and record the data below. this data is invalid. what is the most likely reason why it is invalid? the ruler is marked in centimeters, but zoe recorded data in inches. the range of lengths is too wide, so zoe must have misread the ruler. marla’s complicated measuring procedure was overly confusing. marla could have been inconsistent while drawing outlines of fingers.

Which of these best describes what occurs during cytokinesis? a) the chromosomes are separated b) the cell begins to divide by replicating the chromosomes c) the cytoplasm is divided between the two new daughter cells d) the nucleus opens to allow the chromosomes to enter the cytoplasm

Cells destroy body cells infected by a virus or bacteria.