Exam 1: Studying Life

Biologists have discovered through research on bacteria that they can use enzymes from these organisms to make specific changes of their choosing in the DNA of living bacterial cells.Are these discoveries relevant to people in their everyday lives? Why or why not?

Which is not something that a governmental institute should consider in crafting public policy?

Sea squirts are marine organisms that have a simple bag-like body structure.The sea squirt draws water through slits in its body into the body interior.It filters food from the moving water and squirts the water along with waste materials through an opening in its body.What is likely true about the sea squirt's body cells?

Suppose fish caught at one location in a bay are tagged with simple, numbered, plastic tags.Which kind of information can a scientist gain if she catches one of these fish in another bay distant from the first?

Which statement represents a scientific point of view?

What is the significance of the fact that mitochondria and chloroplasts contain the DNA that instructs their form and function?

Which event was most directly responsible for increasing oxygen in Earth's atmosphere?

Which statement is correct?

Which is a reason to use statistics to evaluate data?

Frogs are amphibians and spend time both on land and in water.Female frogs are vulnerable to predation by fish when they enter the water to lay eggs.A hypothesis has been proposed that frogs rely on chemical detection of predators in addition to visual detection.In other words, frogs detect the presence of predator fish by chemicals released by fish into the water.In designing an experiment to test this hypothesis, a scientist constructed two test ponds that were identical except for the presence of compounds released by fish.This condition was the only _______ that differed in the two setups used in the experiment.

Which question cannot be answered by means of the hypothesis-and-prediction approach?

_______ are structural, physiological, or behavioral traits that enhance an organism's chance of survival and reproduction in its environment.

Bacteria can be used as a model system to study chemical reactions in cells.These reactions can be related to similar processes in humans because bacteria and humans

A research group hypothesizes that diet influences the distribution of bacterial species inhabiting the human digestive system.The researchers define two populations with very different diets-one in England and another in Africa-for sample collection.They take fecal samples from each group and measure the percentage of each species of bacteria present in the samples.How is this investigation classified and why?

Platelets are cell fragments that are critical for blood clotting, a process that involves the release of proteins from platelet storage granules.Platelet granules contain approximately 300 different proteins.One hypothesis about the packaging of proteins into these granules is that each protein is delivered in precisely measured amounts to each granule.An alternative hypothesis is that each protein is targeted to the individual storage granules randomly.The second hypothesis is an example of a(n) _______ hypothesis.

A scientist has isolated the same gene from ten different species.Once these ten pieces of DNA have been sequenced, the scientist will line up the sequences to compare them.She should be able to draw conclusions about the evolutionary relationships among these ten species by using the following as a guide: The _______ the _______ in gene sequences for two species, the _______ the time span since these species diverged from a common ancestor during their evolution.

Which sequence gives the correct ordering of levels from smallest to largest?

Charles Darwin called the differential survival and reproduction among individuals in a population _______.

The information needed to produce proteins is contained in

In the scientific method, a hypothesis is