(HARDIN, 2022) CHAPTER 1-26 | ALL CHAPTERS,140 VERIFIED
AND CORRECT ANSWER ALREADY GRADED A+
1. Cell Theory Foundations
Cell theory established the idea that all living organisms are composed of
cells
and that cells arise only from pre-existing cells. Which scientists are most
closely associated with this theory?
A. Hooke and van Leeuwenhoek
B. Schleiden and Schwann
C. Watson and Crick
D. Mendel and Darwin
Correct Answer: B
Explanation: Schleiden and Schwann formulated the cell theory in the 19th
century, later expanded by Virchow.
2. Prokaryotic vs. Eukaryotic Cells
One major structural difference between prokaryotic and eukaryotic cells
involves the presence of:
distinct, membrane-bound organelles within the cytoplasm.
A. Cell walls
B. Membrane-bound nuclei
,C. Ribosomes
D. Plasma membranes
Correct Answer: B
Explanation: Eukaryotic cells have a true nucleus; prokaryotes lack
membrane-bound nuclei.
3. Microscopy Contributions
Early discoveries about cells were made possible primarily through the
development
of which scientific tool?
A. X-ray crystallography
B. Light microscope
C. Ultracentrifuge
D. Spectrophotometer
Correct Answer: B
Explanation: The light microscope allowed Hooke and others to visualize
and describe cells for the first time.
4. Endosymbiotic Theory
The endosymbiotic theory proposes that mitochondria and chloroplasts
originated as:
independent prokaryotic organisms engulfed by ancestral eukaryotic cells.
A. Products of spontaneous generation
B. Extensions of the endoplasmic reticulum
C. Modified Golgi vesicles
D. Former free-living bacteria
Correct Answer: D
Explanation: Evidence such as their own DNA supports their bacterial
origins through endosymbiosis.
,5. Basic Cell Structure
All cells, regardless of type, share three basic features:
a plasma membrane, cytoplasm, and which of the following?
A. Ribosomes for protein synthesis
B. A nucleus for genetic material
C. A cell wall for protection
D. Chloroplasts for photosynthesis
Correct Answer: A
Explanation: Ribosomes are universal to all cells, prokaryotic and
eukaryotic, for translation of proteins.
6. Surface Area-to-Volume Ratio
Cell size is limited primarily by the relationship between surface area and
volume,
because efficient exchange of materials depends on:
A. High volume and low surface area
B. Low volume and high surface area
C. Equal surface area and volume
D. Cell wall permeability
Correct Answer: B
Explanation: A higher surface area-to-volume ratio allows better diffusion
and transport efficiency.
7. Cytoskeleton Role
The cytoskeleton provides structural support and also contributes to:
intracellular transport, cell movement, and shape maintenance.
, A. Protein synthesis
B. Genetic replication
C. Energy storage
D. Cellular organization and motility
Correct Answer: D
Explanation: Cytoskeletal elements like microtubules and actin filaments
maintain shape and enable transport.
8. Ribosome Function
Ribosomes are the cellular structures responsible for:
assembling amino acids into polypeptides according to mRNA instructions.
A. DNA replication
B. Protein synthesis
C. Lipid modification
D. ATP breakdown
Correct Answer: B
Explanation: Ribosomes read mRNA and catalyze peptide bond formation
during translation.
9. Plasma Membrane Composition
The fluid mosaic model describes the plasma membrane as a phospholipid
bilayer
with embedded proteins that allow for dynamic movement and selective
transport.
A. Fixed and rigid structure
B. Mostly protein without lipids
C. Static arrangement of molecules
D. Flexible bilayer with proteins floating