Biology Term 1A Semester Exam

Which of these is a defining characteristic in a eukaryotic cell?

• The presence of a membrane bound nucleus

• DNA is present

• Absence of membrane bound mitochondria

• Reproduces asexually

Prokaryotes are single-celled organisms belonging to the Domains: Archaea and Bacteria. Which of the following cell structures would not be present in prokaryotic cells?

• cell membrane

• ribosome

• nucleus

• cytoplasm

The cell structure labeled X is found only in –

• animal cells

• eukaryotic cells

• plant cells

• prokaryotic cells

Which of the following is a defining characteristic of a prokaryotic cell?

• Absence of a membrane bound nucleus

• The method of cellular respiration

• The composition of the cell membrane

• The method of movement

Which of the following is not a lipid?

• steroid

• cholesterol

• wax

• cellulose

Which of the following macromolecules are a prominent part of animal tissues that function in insulation, helping animals conserve heat?

• carbohydrates

• lipids

• proteins

• nucleic acids

The enzymes that catalyze cellular reactions are macromolecules called proteins. Which of the following elements most often compose proteins?

• carbon and hydrogen

• carbon, hydrogen, oxygen, and nitrogen

• carbon, hydrogen, and oxygen

• carbon, hydrogen, oxygen, nitrogen, and phosphorus

A biomolecule that is a large, complex set of chains composed of alternating subunits called nucleotides has which of these functions in the cell?

• Storing energy

• Catalyzing cellular reactions

• Building tissue

• Storing genetic information

Which of the following is a characteristic of carbohydrates?

• Provides structure for cells

• Provides energy for all cellular activities

• Contain complex carbohydrates known as starches

• All of the above

Taq polymerase is an enzyme used in the polymerase chain reaction (PCR) to replicate fragments of DNA. A study published in 1976 examined the properties of Taq polymerase after the enzyme was isolated from Thermus aquaticus, a thermophilic bacterium that lives in the hot springs of Yellowstone National Park. The graph shows one of the results of the study. Which statement about enzyme activity is best supported by this graph?

• An enzyme must be composed of multiple polypeptides, or subunits, to be active

• An enzyme's rate of activity increases with time until it becomes active

• An enzyme functions best under specific temperature conditions

• An enzyme works equally well in bacteria that are adapted to high temperatures and in eukaryotic cells such as human cells