Cuestionario: Biology and Chemistry Exam Prep — 10 preguntas

1. Which property of water is primarily responsible for its ability to support transport of nutrients in plants and animals?

A. Cohesion between water molecules

B. Water's polarity

C. Water's density anomaly

D. Water's high specific heat

Answer: (A)

Explicación

Cohesion, the attraction between water molecules, allows water to form continuous columns in plant xylem and facilitates transport in animals. This property is crucial for capillary action and movement of water through biological systems.

2. Which property of water contributes to its ability to support temperature regulation in organisms?

A. High specific heat capacity

B. Cohesion due to polarity

C. Rapid evaporation rate

D. Low surface tension

Answer: (A)

Explicación

Water's high specific heat capacity allows it to absorb and retain heat, helping organisms regulate temperature. While cohesion and surface tension are related to water's polarity, they do not directly influence temperature regulation as much as specific heat does.

3. Which organic molecule is primarily responsible for storing genetic information in cells?

A. Carbohydrates

B. Nucleic acids

C. Lipids

D. Proteins

Answer: (B)

Explicación

Nucleic acids, such as DNA and RNA, store and transmit genetic information essential for inheritance and cellular function.

4. Who proposed the cell theory that states all living organisms are made of cells and cells arise from pre-existing cells, and in what year was it published?

A. Matthias Schleiden and Theodor Schwann, 1838-1839

B. Louis Pasteur, 1864

C. Robert Hooke, 1665

D. Whooping Crane, 1880

Answer: (A)

Explicación

Matthias Schleiden and Theodor Schwann formulated the cell theory during 1838-1839, establishing that all living things are composed of cells and that cells come from existing cells. Louis Pasteur contributed to germ theory, and Robert Hooke first described cells earlier in 1665.

5. What type of chemical bond is primarily responsible for the formation of salts like sodium chloride?

A. Covalent bonds

B. Van der Waals forces

C. Ionic bonds

D. Hydrogen bonds

Answer: (C)

Explicación

Ionic bonds involve the transfer of electrons from one atom to another, resulting in oppositely charged ions that attract each other. Salts like sodium chloride are formed through ionic bonds between sodium and chloride ions.

6. Which type of chemical bond involves the transfer of electrons and is characteristic of salts?

A. Ionic bond

B. Covalent bond

C. Hydrogen bond

D. Van der Waals forces

Answer: (A)

Explicación

Ionic bonds involve the transfer of electrons from one atom to another, forming salts. Covalent bonds involve sharing electrons, and hydrogen bonds are attractions between polar molecules, not transfer of electrons.

7. Which organelle is primarily responsible for ATP production in eukaryotic cells?

A. Mitochondria

B. Chloroplasts

C. Nucleus

D. Ribosomes

Answer: (A)

Explicación

Mitochondria are known as the powerhouses of the cell because they produce ATP through cellular respiration, unlike chloroplasts (photosynthesis), the nucleus (genetic information), or ribosomes (protein synthesis).

8. What is the primary function of lipids within biological organisms?

A. Long-term energy storage and membrane structure

B. Genetic information storage

C. Catalyzing biochemical reactions

D. Transport of oxygen in blood

Answer: (A)

Explicación

Lipids serve as long-term energy storage molecules and are key components of cell membranes, such as phospholipids. They are not primarily involved in genetic information storage, enzyme activity, or oxygen transport.

9. Which organic molecule is characterized by monomers called amino acids, and performs functions such as enzymatic activity and structural support?

A. Proteins

B. Carbohydrates

C. Lipids

D. Nucleic acids

Answer: (A)

Explicación

Proteins are made of amino acids linked together, and they perform a variety of functions including acting as enzymes and providing structural support. Carbohydrates, lipids, and nucleic acids have different monomers and functions.

10. What is the primary structural difference between prokaryotic and eukaryotic cells?

A. Eukaryotic cells contain membrane-bound organelles, while prokaryotic cells do not

B. Prokaryotic cells have a nucleus, while eukaryotic cells do not

C. Eukaryotic cells are unicellular, while prokaryotic cells are multicellular

D. Prokaryotic cells have a nucleus, while eukaryotic cells have nucleoid regions

Answer: (A)

Explicación

Eukaryotic cells have membrane-bound organelles such as the nucleus, whereas prokaryotic cells lack these structures. Both cell types can be unicellular, but the key difference is the presence of organelles.