Cell Biology - Assessment #1 [Practice]

Which of the following statements is a part of the Cell Theory?

• All cells have a nucleus.

• All living organisms are composed of one or more cells.

• Cells can arise spontaneously from non-living matter.

• Cells are the smallest unit of matter.

Answer explanation

The correct statement from the Cell Theory is that all living organisms are composed of one or more cells. This principle emphasizes that cells are the fundamental building blocks of life.

Which of the following is a key difference between prokaryotic and eukaryotic cells?

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

• Eukaryotic cells have membrane-bound organelles, while prokaryotic cells do not.

• Prokaryotic cells are generally larger than eukaryotic cells.

• Eukaryotic cells have a cell wall, while prokaryotic cells do not.

Answer explanation

Eukaryotic cells are characterized by having membrane-bound organelles, such as the nucleus, which are absent in prokaryotic cells. This distinction is fundamental in cell biology.

Which organelle is responsible for energy production in eukaryotic cells?

• Ribosome

• Golgi apparatus

• Mitochondria

• Lysosome

Answer explanation

The mitochondria are known as the powerhouse of the cell, as they are responsible for producing ATP, the main energy currency in eukaryotic cells. Other organelles like ribosomes, Golgi apparatus, and lysosomes have different functions.

Which of the following is a characteristic of plant cells but not animal cells?

• Presence of a cell membrane

• Presence of chloroplasts

• Presence of mitochondria

• Presence of ribosomes

Answer explanation

Chloroplasts are organelles found in plant cells that enable photosynthesis, a process not present in animal cells. While both cell types have membranes, mitochondria, and ribosomes, chloroplasts are unique to plants.

Which kingdom of life includes organisms that are primarily unicellular and lack a nucleus?

• Plantae

• Animalia

• Fungi

• Bacteria

Answer explanation

Bacteria are unicellular organisms that lack a nucleus, distinguishing them from the other kingdoms listed, which include multicellular organisms or those with a nucleus.

What is the primary function of the ribosome in a cell?

• DNA replication

• Protein synthesis

• Lipid synthesis

• Energy production

Answer explanation

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

Identify the organelle described: "A network of membranes involved in protein and lipid synthesis."

• Golgi apparatus

• Endoplasmic reticulum

• Lysosome

• Nucleus

Answer explanation

The endoplasmic reticulum (ER) is a network of membranes that plays a crucial role in the synthesis of proteins and lipids, making it the correct answer. The Golgi apparatus processes proteins, while lysosomes and the nucleus serve different functions.

Which of the following is NOT a function of the Golgi apparatus?

• Modifying proteins

• Packaging proteins

• Synthesizing lipids

• Transporting proteins

Answer explanation

The Golgi apparatus modifies, packages, and transports proteins, but it does not synthesize lipids. Lipid synthesis primarily occurs in the smooth endoplasmic reticulum, making 'synthesizing lipids' the correct answer.

Which organelle is responsible for breaking down waste materials and cellular debris?

• Mitochondria

• Lysosome

• Chloroplast

• Ribosome

Answer explanation

The lysosome is the organelle responsible for breaking down waste materials and cellular debris. It contains enzymes that digest unwanted substances, making it essential for cellular cleanup and recycling.

Which of the following is a similarity between plant and animal cells?

• Both have a cell wall.

• Both have chloroplasts.

• Both have a nucleus.

• Both have large central vacuoles.

Answer explanation

Both plant and animal cells contain a nucleus, which houses genetic material and controls cellular activities. The other options, such as cell walls and chloroplasts, are specific to plant cells.