The cell membrane is composed primarily of a phospholipid bilayer.
Correct Answer
True
The cell membrane (plasma membrane) is made of two layers of phospholipids with their hydrophobic tails facing inward and hydrophilic heads facing outward.
Category: Chapter 3
Question 2
The nucleus contains the cell's mitochondria.
Correct Answer
False
The nucleus contains the cell's DNA (chromosomes) and the nucleolus. Mitochondria are organelles found in the cytoplasm outside the nucleus.
Category: Chapter 3
Question 3
Active transport requires energy in the form of ATP.
Correct Answer
True
Active transport moves substances against their concentration gradient (from low to high concentration), which requires energy from ATP hydrolysis.
Category: Chapter 3
Question 4
Osmosis is the diffusion of solute molecules across a selectively permeable membrane.
Correct Answer
False
Osmosis is the diffusion of water (not solute) molecules across a selectively permeable membrane from an area of lower solute concentration to higher solute concentration.
Category: Chapter 3
Question 5
Ribosomes are responsible for protein synthesis.
Correct Answer
True
Ribosomes are the sites of protein synthesis. They can be free in the cytoplasm or attached to the rough endoplasmic reticulum.
Category: Chapter 3
Question 6
The smooth endoplasmic reticulum is studded with ribosomes.
Correct Answer
False
The rough endoplasmic reticulum is studded with ribosomes, giving it a 'rough' appearance. The smooth ER lacks ribosomes and is involved in lipid synthesis and detoxification.
Category: Chapter 3
Question 7
Lysosomes contain digestive enzymes that break down waste materials.
Correct Answer
True
Lysosomes are membrane-bound organelles containing hydrolytic enzymes that digest worn-out cell parts, food particles, and engulfed bacteria.
Category: Chapter 3
Question 8
In a hypertonic solution, a cell will swell and potentially burst.
Correct Answer
False
In a hypertonic solution (higher solute concentration outside the cell), water moves out of the cell by osmosis, causing the cell to shrink (crenate). Cells swell in hypotonic solutions.
Category: Chapter 3
Question 9
Mitosis produces two genetically identical daughter cells.
Correct Answer
True
Mitosis is the division of the nucleus that results in two daughter cells, each with the same number and type of chromosomes as the parent cell.
Category: Chapter 3
Question 10
The Golgi apparatus packages and modifies proteins for secretion.
Correct Answer
True
The Golgi apparatus (Golgi complex) receives proteins from the rough ER, modifies and packages them into vesicles for secretion or use within the cell.
Category: Chapter 3
Question 11
Diffusion requires energy input from the cell.
Correct Answer
False
Diffusion is a passive process that does not require energy. Molecules move from areas of higher concentration to lower concentration due to their own kinetic energy.
Category: Chapter 3
Question 12
DNA replication occurs during the S phase of the cell cycle.
Correct Answer
True
The S (synthesis) phase is when DNA is replicated so that each daughter cell will receive a complete copy of the genetic material during cell division.
Category: Chapter 3
Question 13
Cilia and flagella have the same basic internal structure.
Correct Answer
True
Both cilia and flagella contain a core of microtubules arranged in a 9+2 pattern (nine peripheral doublets surrounding two central singlets). Cilia are shorter and more numerous while flagella are longer.
Category: Chapter 3
Question 14
The cytoskeleton is a rigid, permanent structure within the cell.
Correct Answer
False
The cytoskeleton is a dynamic network of protein filaments (microfilaments, intermediate filaments, and microtubules) that constantly assembles and disassembles to change cell shape and enable movement.
Category: Chapter 3
Question 15
Pinocytosis is a form of endocytosis that engulfs large solid particles.
Correct Answer
False
Pinocytosis ('cell drinking') engulfs extracellular fluid and dissolved solutes. Phagocytosis ('cell eating') engulfs large solid particles like bacteria.
Category: Chapter 3
Question 16
Interphase is the longest phase of the cell cycle.
Correct Answer
True
Interphase (G1, S, and G2 phases) typically accounts for about 90% of the cell cycle. This is the period of cell growth and DNA replication between divisions.
Category: Chapter 3
Question 17
Peroxisomes are organelles that produce hydrogen peroxide to detoxify harmful substances.
Correct Answer
True
Peroxisomes contain enzymes that use oxygen to detoxify harmful substances including alcohol and free radicals. They produce hydrogen peroxide as a byproduct, then break it down.
Category: Chapter 3
Question 18
Facilitated diffusion moves substances against their concentration gradient.
Correct Answer
False
Facilitated diffusion moves substances down their concentration gradient (high to low) using transport proteins. It is a passive process that does not require ATP.
Category: Chapter 3
Question 19
Apoptosis is uncontrolled cell death caused by injury.
Correct Answer
False
Apoptosis is programmed cell death, a controlled and orderly process. Necrosis is uncontrolled cell death caused by injury, infection, or loss of blood supply.
Category: Chapter 3
Question 20
The nucleolus is responsible for producing ribosomal RNA.
Correct Answer
True
The nucleolus is a dense region within the nucleus where ribosomal RNA (rRNA) is synthesized and ribosomal subunits are assembled.
Category: Chapter 3