WorksheetsUnit 5 Review (Part 1)
Total questions: 61
Worksheet time: 31mins
Which statement best explains why very large cells are inefficient at meeting their needs?
The cell membrane becomes thicker to slow transport
The surface area to volume ratio becomes larger
The surface area to volume ratio becomes smaller
The DNA instructions become less accurate over time
What problem would occur if a cell grew too large without dividing?
ATP would automatically increase without regulation
Ribosomes would fuse and stop translation entirely
Mitochondria would disappear from the cytoplasm
DNA would be overloaded producing needed proteins
Maintaining a high surface area to volume ratio helps a cell primarily by improving which function?
Storage of genetic material in the nucleus
Stability of the phospholipid bilayer
Exchange of materials across the membrane
Synthesis of membrane-bound organelles
Which scenario most likely triggers cell division in healthy tissues?
When diffusion no longer meets metabolic demands
When the genome duplicates arbitrary extra genes
When lysosomes digest excess plasma membrane
When the membrane potential becomes slightly positive
Compare asexual and sexual reproduction: which pairing is accurate?
Asexual increases genetic variation in populations
Sexual yields genetically identical offspring
Sexual requires only a single parent organism
Asexual yields genetically identical offspring
Which example illustrates a form of asexual reproduction in multicellular organisms?
Meiosis forming haploid gametes
Crossing over during prophase I
Budding in hydra producing a clone
Fertilization creating a zygote
Two cubic cells differ in size. Cell A has twice the edge length of Cell B. Which statement is correct about their surface area to volume ratios?
Cell A has a higher ratio than Cell B
Both cells have identical ratios and transport
Cell A has a lower ratio than Cell B
Ratios are irrelevant to transport efficiency
A tissue relies on rapid nutrient uptake. Which cell morphology best supports this requirement?
Small cells with many microvilli
Large cells with minimal membrane
Spherical cells with reduced area
Thick cells with low ratio
Which statement best distinguishes asexual reproduction from sexual reproduction at the cellular level?
Sexual reproduction requires mitotic division of a single cell
Sexual reproduction produces genetically identical daughter cells
Asexual reproduction fuses two gametes to form zygotes
Asexual reproduction uses one parent cell to produce clones
In budding, what most accurately describes the origin of the new individual?
An outgrowth detaches from a single parent organism
Two parental gametes fuse to form an embryo
A spore disperses and develops independently
A fertilized ovule grows within a flower
Vegetative propagation in plants primarily results in offspring with which genetic relationship to the parent?
Genetically mixed from two parent plants
Genetically identical to the parent organism
Genetically unrelated to the parent plant
Genetically reduced relative to the parent
Which outcome most directly explains why sexual reproduction can enhance a species’ long‑term survival in changing environments?
Single-parent reproduction conserves more energy
Parent-offspring genomes remain identical
Rapid cloning maximizes population growth
Genetic mixing increases variation among offspring
Most unicellular organisms primarily reproduce by which mechanism, and what is a key consequence for genetic diversity?
Cross-fertilization producing extreme genetic variation
Asexual division producing low genetic variation
Sexual fusion producing high genetic variation
Spore formation producing moderate genetic variation
A research team compares hydra budding with human reproduction. Which pairing correctly matches process to genetic outcome?
Hydra budding—offspring reduced genomes; human reproduction—offspring reduced genomes
Hydra budding—offspring unrelated; human reproduction—offspring unrelated
Hydra budding—offspring are clones; human reproduction—offspring are genetically mixed
Hydra budding—offspring genetically mixed; human reproduction—offspring are clones
In a eukaryotic cell, where is the genetic material primarily located?
Freely in the cytoplasm
Attached to ribosome surfaces
Embedded in the cell wall
Inside the nucleus region
During most of a eukaryotic cell’s life cycle, DNA exists mainly as which form?
Tightly packed chromatids
Long strands called chromatin
Separated sister chromosomes
Short fragments called plasmids
What is the primary reason chromatin condenses when a cell divides?
To prevent tangling and breakage
To increase gene transcription
To export DNA from nucleus
To lengthen interphase duration
Which proteins serve as spools around which DNA winds to form higher-order structure?
Tubulins in microtubules
Kinesins on chromosomes
Polymerases on templates
Histones in nucleosomes
The X-shaped structure visible during mitosis is best described as what?
A circular DNA plasmid
A single chromatid fiber
A condensed chromosome
A histone protein core
Which statement best contrasts eukaryotic and prokaryotic genetic organization?
Eukaryotes use histones; prokaryotes lack any proteins
Eukaryotes have one chromosome; prokaryotes have many
Eukaryotes store DNA in cytoplasm; prokaryotes in nucleus
Eukaryotes have linear chromosomes; prokaryotes have circular DNA
A bacterial cell’s genome is most often contained in which structural form?
A single circular DNA molecule
Multiple linear chromosomes
Many X-shaped chromatids
Numerous mitochondrial DNAs
If histone-DNA interactions were experimentally weakened during cell division, which outcome would be most likely?
Chromosomes would fail to condense properly
Transcription rates would immediately cease
Cell membranes would lose integrity
Ribosomes would stop protein synthesis
Which observation would best indicate a cell is not currently dividing?
Numerous X-shaped chromosomes
Diffuse chromatin strands in nucleus
Spindle microtubules attached kinetochores
Separated sister chromatids at poles
Which statement best explains why cells organize DNA into chromosomes during division?
To protect genetic information during segregation
To increase mutation rates for adaptation
To reduce the amount of cellular DNA overall
To stop transcription throughout the cell
Which process describes how most prokaryotes reproduce?
Binary fission producing identical cells
Meiosis producing varied gametes
Mitosis producing diploid spores
Budding producing unequal daughter cells
What is the immediate result of DNA replication during binary fission?
Four chromatids forming homologous pairs
Separated daughter cells with membranes
Two copies of the circular chromosome
A condensed metaphase chromosome
During which general phase do eukaryotic cells spend most of their time?
M phase focused on chromosome movement
G0 exit focused on permanent inactivity
Cytokinesis focused on cytoplasm splitting
Interphase focused on growth and work
Arrange these interphase subphases in the correct chronological order: G1, S, G2.
G2 then G1 then S
G1 then G2 then S
S then G2 then G1
G1 then S then G2
Which event characterizes the S phase of interphase?
Duplication of DNA molecules
Separation of sister chromatids
Assembly of mitotic spindle
Active cytokinesis of cytoplasm
A bacterium divides and produces two daughter cells with the same genome. Which feature makes this likely?
Replication followed by pinching in half
Crossing over during prophase I
Independent assortment of chromosomes
Fusion of two parental gametes
Which comparison between binary fission and mitosis is accurate?
Both require formation of meiotic tetrads
Both involve homologous recombination events
Both reduce chromosome number by half
Both yield genetically identical daughter cells
A eukaryotic cell spends only a small fraction of its cycle in mitosis. What is the best explanation?
Cytokinesis requires more time than growth
Most time is needed for growth and preparation
DNA cannot replicate outside mitosis
Division machinery works extremely slowly
Which sequence best matches the major events of binary fission?
Chromosome condensation, crossing over, cytokinesis
DNA replication, chromosome segregation, cytokinesis
Spindle assembly, metaphase alignment, telophase
Gamete production, fertilization, zygote cleavage
Which event defines the S phase of interphase?
Cell copies its chromosomes
Cell exits the cell cycle
Cell grows and makes proteins
Cell divides its cytoplasm
What primary activity occurs during G1 of interphase?
Cell grows and duplicates organelles
Chromosomes align at the midline
Nuclear envelope re-forms around DNA
Sister chromatids separate to poles
During G2, which checkpoint-related action is emphasized?
DNA condenses into visible chromosomes
Spindle fibers disassemble completely
Cell checks duplicated chromosomes
Centromeres split and chromatids move
Why must chromosomes be copied before mitosis?
To ensure each new cell has the same genetic information
To allow cells to grow larger than normal size
To create genetic diversity in daughter cells
To reduce the number of chromosomes by half
Which list shows the four main phases of mitosis in correct order?
Telophase, Anaphase, Metaphase, Prophase
Anaphase, Prophase, Metaphase, Telophase
Metaphase, Prophase, Telophase, Anaphase
Prophase, Metaphase, Anaphase, Telophase
Which phase is primarily responsible for splitting the cytoplasm into two cells?
Telophase
Metaphase
Cytokinesis
Prophase
A drug prevents chromosome duplication but allows mitosis to proceed. Predict the most likely outcome.
Daughter cells with incomplete genetic information
Daughter cells with extra cytoplasm only
Daughter cells with increased chromosome numbers
Daughter cells identical and genetically stable
A cell has just completed telophase with two nuclei formed. What event must occur to finish producing two separate daughter cells?
S phase to copy chromosomes
G1 to duplicate organelles
Metaphase to align chromosomes
Cytokinesis to divide the cytoplasm
In the diagram of prophase, which event occurs first to make chromosomes visible?
Chromatin coils into chromosomes
Centrioles replicate at the poles
Sister chromatids move to opposite poles
Nuclear envelope reforms around DNA
During prophase, what is the primary role of the centrioles shown near the cell edges?
Organize spindle microtubule assembly
Duplicate sister chromatids at centromeres
Digest the nuclear envelope fragments
Drive cytokinesis of the cytoplasm
Which statement best describes metaphase as shown in the diagram?
Chromosomes decondense into chromatin
Nuclear envelope encloses the spindle
Spindle fibers disassemble completely
Chromosomes align at the cell equator
In metaphase, how do spindle fibers interact with chromosomes in the diagram?
Slide chromatids past each other
Connect telomeres to opposite poles
Bind randomly along chromatid arms
Attach to centromeres via kinetochores
A duplicated chromosome consists of what, as labeled in the inset diagram?
Two identical sister chromatids
Two different homologous chromosomes
One chromatid and one centrosome
One chromatid and its telomere
If the spindle fibers failed to attach to one centromere in metaphase, which immediate outcome is most likely during the next phase?
Non-disjunction of sister chromatids
Premature nuclear envelope formation
Instant chromosome decondensation
Rapid cytokinesis without karyokinesis
Which sequence correctly orders the events from prophase to metaphase in the diagrams?
Spindle disassembles, chromatids pair, nuclear envelope forms, chromosomes align
Nuclear envelope reforms, chromatin condenses, spindle collapses, chromosomes align
Chromosomes align, spindle forms, nuclear envelope reforms, chromatids separate
Chromatin condenses, spindle forms, nuclear envelope breaks down, chromosomes align
In the diagram of anaphase, which event best explains why each future daughter cell will receive an identical set of chromosomes?
Centromeres split and chromatids separate
Spindle fibers assemble from tubulin
Chromosomes condense into thick coils
Nuclear envelope fragments into vesicles
Which statement best matches the telophase diagram showing two nuclei forming?
Centromeres split to free chromatids
Chromosomes align at the cell equator
Nuclear envelopes reform around chromosomes
Spindle fibers attach to kinetochores
In the cytokinesis diagram, what structure divides the cytoplasm in plant cells?
A cell plate grows inward
A cleavage furrow pinches
Centrioles constrict filaments
Microtubules sever cytoplasm
According to the anaphase image, what role do spindle fibers play at this stage?
They anchor chromosomes at the metaphase plate
They replicate DNA for chromatid doubling
They pull sister chromatids to opposite poles
They dissolve the nuclear envelope remnants
Which feature distinguishes animal from plant cytokinesis as shown in the diagrams?
Nuclear envelope breakdown versus spindle assembly
Membrane pinching versus cell plate formation
Chromatid cohesion versus kinetochore disassembly
Centriole duplication versus chromosome condensation
Which sequence of events is most consistent with the diagrams from anaphase to telophase?
Cytokinesis starts → metaphase forms → genetic recombination
Nuclear envelopes break → chromosomes pair → cytokinesis pauses
Chromosomes condense → spindle forms → DNA replicates
Centromeres split → chromatids separate → nuclei reform
In telophase, why do spindle fibers disappear as shown in the diagram?
Kinetochores are forming for metaphase
DNA replication begins on spindle tracks
Centromeres require free tubulin to divide
Chromosome movement has finished at the poles
Which observation would confirm a cell is in anaphase rather than telophase based on the diagrams?
A deep cleavage furrow constricting the membrane
Sister chromatids moving apart toward poles
Chromosomes decondensed into diffuse chromatin
Two distinct nuclear envelopes surrounding DNA
During cytokinesis in animal cells, which structure creates the cleavage furrow illustrated?
A cellulose-rich cell plate
A kinetochore microtubule belt
A centromere protein scaffold
An actin–myosin contractile ring
Two daughter cells appear with newly formed nuclei and separated cytoplasm. Which mitotic phase has just concluded according to the diagrams?
S phase of interphase
Anaphase before chromatid split
Prophase before metaphase
Cytokinesis completing telophase
What is the immediate cellular outcome of mitosis in typical somatic cells?
Two nonidentical gamete cells form
Two identical daughter cells form
Four unique daughter cells form
One larger polyploid cell forms
A parent cell with a diploid chromosome number undergoes mitosis. Which statement best describes the daughter cells?
They are haploid and genetically identical
They are diploid and genetically identical
They are haploid and genetically variable
They are diploid and genetically variable
A researcher observes two daughter cells after mitosis that differ genetically from the parent cell. Which scenario most plausibly explains this observation?
Independent assortment created new alleles
Crossing over during metaphase occurred
Reduction division halved chromosome number
A replication error produced mutations
