Biology Self-Analysis

How do stem cells know what type of cells to differentiate into? (1)

• The nucleus has instructions to turn some genes on and some genes off.

• Signals from chemicals in the organism or from the environment determine which genes will be turned on and off.

• Genes turn on and off randomly.

• The cell has unique DNA that determines what the cell will become.

Which statements can apply to

eukaryotic cells? (1)

I. Unicellular

II. Phospholipid cell membranes

III. DNA stored in plastids

IV. Enclosed cytoplasm

V. Double-walled nuclear membranes

• I, II, III, IV, V

• II, III, IV

• I, II, IV, V

• II, IV, V

An insertion of a DNA base into a gene can affect an organism by— (2)

• causing future gametes to have additional chromosomes.

• changing the sequence of amino acids in a protein.

• causing chromosome fragments to form long chains.

• changing the structure of ribose sugar in nucleic acids.

A model of a biological process is shown. What is the purpose of this process? (2)

• To replicate the DNA of an organism before cell division

• To assemble nucleotides in an mRNA chain along a DNA template

• To synthesize amino acids used to unzip strands of DNA and copy the genetic code

• To translate the genetic code into a specific sequence of amino acids

An analysis of DNA and RNA sequences can be used to classify organisms. A dendrogram/evolutionary tree, such as the one shown below, is based on molecular data. It can be used to represent evolutionary relationships within a group of organisms that are hypothesized to have descended from a common ancestor.

Which statement is best supported by the information in this dendrogram/evolutionary tree? (3)

• Lesser pandas are more genetically similar to giant pandas than they are to raccoons.

• Brown bears are more genetically similar to giant pandas than they are to sun bears.

• Lesser pandas are more genetically similar to raccoons than they are to giant pandas.

• The bear species are all more genetically similar to dogs than they are to giant pandas.

Which of the following is an example of the founder effect? (3)

• Bald Eagles are hunted until near extinction, population recovers.

• Small group of iguanas floats to an island, starts a new population.

• Red fox pups are more likely to survive in a snowy environment if they are born white.

• Farmer chooses seeds from largest apples to plant next year. This results in larger apples from year to year.

Which statement best describes the relationship between the products of photosynthesis and the reactants in cellular respiration? (4)

• The products of photosynthesis serve as the reactants in cellular respiration to provide chemical energy.

• The products of photosynthesis combine with the reactants in cellular respiration to remove ATP from cells.

• The products of photosynthesis inhibit the reactants in cellular respiration in the presence of light.

• The products of photosynthesis change the structure of the reactants in cellular respiration in the presence of light.

The complex carbohydrates pictured below are made by linking molecules of glucose. In all three complex carbohydrates, the subunits of glucose are bonded together differently. Because they have different structures, they most likely — (4)

• contain different chemical elements

• form different proteins

• carry different nucleotides

• perform different functions

In the food chain, how much energy will make it to the trophic level of the sharks if the producers have 100,000 calories? (5)

• 10 calories

• 1 calorie

• 100 calories

• 1,000 calories

Why does secondary succession have more species diversity than primary succession? (5)

• There is no species diversity.

• Secondary succession has more species diversity due to the lack of soil.

• Secondary succession has more species diversity due to the microorganisms that survived in the soil.

• Primary succession ALWAYS has more species diversity.