BIOL 20 - Lecture Exam 1 Practice

What's the first step in the scientific method?

• Come up with a question

• Observe something of interest

• Perform an experiment

• Report your results

What is the binomial naming system used for?

• Classifying organisms by genus and species

• Naming chemical compounds

• Identifying atomic structures

• Labeling geological formations

Answer explanation

The binomial naming system is used for classifying organisms by their genus and species, providing a standardized way to identify and categorize living things, unlike the other options which pertain to different scientific fields.

Which of the following is NOT one of the three domains of life?

• Plantae

• Bacteria

• Archaea

• Eukarya

Answer explanation

Plantae is a kingdom, not a domain. The three domains of life are Bacteria, Archaea, and Eukarya, which categorize all living organisms based on cellular structure and genetic makeup.

Tags

NGSS.HS-LS4-1

Which subatomic particle is found orbiting around the nucleus?

• Electron

• Proton

• Neutron

• Isotope

Answer explanation

The electron is the subatomic particle that orbits around the nucleus of an atom. Protons and neutrons are found within the nucleus, while isotopes refer to variants of elements, not specific particles.

What is the main difference between ionic bonds and covalent bonds?

• Ionic bonds involve electron sharing, while covalent bonds involve electron transfer.

• Ionic bonds involve electron transfer, while covalent bonds involve electron sharing.

• Both ionic and covalent bonds involve electron sharing.

• Both ionic and covalent bonds involve electron transfer.

Answer explanation

Ionic bonds form when electrons are transferred from one atom to another, creating charged ions. In contrast, covalent bonds involve the sharing of electrons between atoms. Thus, the correct choice highlights this distinction.

Tags

NGSS.HS-PS1-3

Why is water considered polar?

• Because it has an equal charge distribution.

• Because it has an unequal charge distribution.

• Because it is hydrophobic.

• Because it is non-polar.

Answer explanation

Water is considered polar because it has a non-uniform charge distribution. The oxygen atom is more electronegative, creating a partial negative charge, while the hydrogen atoms have partial positive charges, leading to polarity.

What is the role of enzymes in chemical reactions?

• They increase the activation energy

• They act as biological catalysts

• They are consumed in the reaction

• They provide energy for the reaction

Answer explanation

Enzymes act as biological catalysts, speeding up chemical reactions by lowering the activation energy required. They are not consumed in the reaction and do not provide energy; instead, they facilitate the reaction process.

Tags

NGSS.MS-PS1-2

What distinguishes prokaryotes from eukaryotes?

• Presence of a nucleus

• Ability to photosynthesize

• Having a cell wall

• Being multicellular

Answer explanation

Prokaryotes lack a nucleus, while eukaryotes have a defined nucleus that houses their genetic material. This is the primary distinction between the two groups, making 'presence of a nucleus' the correct answer.

Tags

NGSS.MS-LS4-2

What is the primary function of ribosomes in a cell?

• DNA storage

• Lipid synthesis

• Protein synthesis

• Digestion

Answer explanation

The primary function of ribosomes in a cell is protein synthesis. They translate messenger RNA (mRNA) into polypeptide chains, which then fold into functional proteins, essential for various cellular processes.

Tags

NGSS.MS-LS1-2

NGSS.MS-LS3-1

What is the main organelle responsible for ATP production in cells?

• Chloroplast

• Mitochondria

• Central vacuole

• Ribosome

Answer explanation

The mitochondria are known as the powerhouse of the cell, as they are responsible for producing ATP through cellular respiration, making them the correct choice for ATP production.

Tags

NGSS.HS-LS1-7