General Biology I - Review Second Quarter

Kaye and Hans are discussing their favorite foods and how they store energy. Kaye mentions that some foods are great for quick energy, while others are better for long-term energy storage. Which biological molecule primarily serves as a long-term energy storage?

• carbohydrates

• lipids

• proteins

• nucleic acids

Answer explanation

Lipids are the primary biological molecules for long-term energy storage due to their high energy density and ability to store more energy per gram compared to carbohydrates, proteins, and nucleic acids.

During a science project, Erika and Hans are exploring how different biological molecules function in the body. They learn that one type of molecule is responsible for forming enzymes that catalyze metabolic reactions. Which type of biological molecule are they studying?

• lipids

• carbohydrates

• proteins

• nucleic acids

Answer explanation

Proteins are the biological molecules that form enzymes, which are crucial for catalyzing metabolic reactions. Unlike lipids, carbohydrates, and nucleic acids, proteins have the specific structure needed for enzymatic activity.

Tags

NGSS.HS-LS1-1

During a biology class, Jaira and Joaquin were discussing the differences between various biological molecules. Jaira mentioned that DNA and RNA are examples of ____.

• proteins

• lipids

• carbohydrates

• nucleic acids

Answer explanation

DNA and RNA are both types of nucleic acids, which are essential biomolecules responsible for storing and transmitting genetic information. The other options (proteins, lipids, carbohydrates) are different classes of macromolecules.

During a science project, Joaquin and Fanella are trying to determine which biological molecule serves as the primary source of immediate energy for their experiment. They have learned about different types of molecules and need to choose the right one. Which biological molecule should they select?

• lipids

• carbohydrates

• proteins

• nucleic acids

Answer explanation

Carbohydrates are the primary source of immediate energy for the body. They are quickly broken down into glucose, which is used by cells for energy, making them essential for rapid energy needs.

During a biology class, Jaira, Joseph, and Kaye were discussing different types of carbohydrates. Jaira mentioned that glycogen, starch, and cellulose are types of ____.

• lipids

• nucleic acids

• carbohydrates

• proteins

Answer explanation

Glycogen, starch, and cellulose are all polysaccharides, which are types of carbohydrates. They serve as energy storage and structural components in living organisms, distinguishing them from lipids, nucleic acids, and proteins.

During a science project, Hans and Joaquin are exploring how plants convert sunlight into energy. They learn that carbohydrates play a critical role as an energy source in this process. In which process do carbohydrates play a critical role as an energy source?

• protein synthesis

• lipid formation

• photosynthesis and cellular respiration

• DNA replication

Answer explanation

Carbohydrates are essential in photosynthesis, where they are produced, and in cellular respiration, where they are broken down to release energy. Thus, they play a critical role as an energy source in both processes.

Tags

NGSS.HS-LS1-5

NGSS.HS-LS1-7

NGSS.HS-LS2-5

In a cooking class, Fanella is trying to make a cake, and she needs to mix the ingredients together. The part of the mixing bowl where she adds the flour is known as ____.

• active site

• substrate site

• product site

• enzyme pocket

Answer explanation

The part of an enzyme where the substrate binds is called the active site. This is the specific region that interacts with the substrate to facilitate the enzyme's catalytic activity.

In a science class, Hans and Fanella are learning about enzymes. They discuss the different components that make up an enzyme's structure. Hans mentions the active site and coenzymes, while Fanella is curious about what else is included. However, she wonders if a phosphate group is part of an enzyme's structure. Which component is NOT part of an enzyme’s structure?

• active site

• coenzymes

• phosphate group

• substrate

Answer explanation

The phosphate group is not a structural component of enzymes. Enzymes consist of an active site, coenzymes, and substrates, which are essential for their catalytic function.

During a science experiment, Fanella and Joaquin were discussing oxidation-reduction reactions. Fanella mentioned that oxidation specifically refers to ___.

• gain of electrons

• loss of electrons

• splitting of molecules

• gain of energy

Answer explanation

During an oxidation-reduction reaction, oxidation specifically refers to the loss of electrons. This is a fundamental concept in redox reactions, where the substance that loses electrons is oxidized.

During a science experiment, Hans and Jaira are studying the effect of temperature on enzyme activity. They notice that when the temperature decreases, the reaction rate of the enzyme slows down. How does a decrease in temperature affect enzyme activity?

• It increases enzyme activity.

• It decreases enzyme activity.

• It has no effect.

• It denatures the enzyme.

Answer explanation

A decrease in temperature generally slows down molecular movement, which reduces the frequency of enzyme-substrate collisions, leading to decreased enzyme activity.