GED Science Quiz: Explain Cellular Processes
20 questions · exam conditions
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Explain Cellular ProcessesQuestion 1 of 20

A cell that requires a large amount of energy, such as a muscle cell, would have a high concentration of which organelle?

Lysosomes
Ribosomes
Mitochondria
Golgi apparatus
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GED Science Quiz

GED Science Quiz: Explain Cellular Processes

Practice Explain Cellular Processes in GED Science with focused quiz questions that help you check what you know, review explanations, and build confidence with test-style prompts.

What this quiz covers

This quiz focuses on Explain Cellular Processes, giving you a quick way to practice the rules, question types, and explanations that matter most for GED Science.

How to use this quiz

Try each quiz question before looking at the correct answer. Use the explanations to review missed ideas, then come back to similar questions until the pattern feels familiar.

All questions

Question 1

A cell that requires a large amount of energy, such as a muscle cell, would have a high concentration of which organelle?

  1. Lysosomes
  2. Ribosomes
  3. Mitochondria (correct answer)
  4. Golgi apparatus
Explanation: When you encounter questions about cellular organelles and energy requirements, think about the relationship between structure and function. Different organelles have specialized roles, and cells with high energy demands will contain more of the organelles responsible for energy production. Mitochondria are the powerhouses of the cell, responsible for producing ATP (adenosine triphosphate) through cellular respiration. A muscle cell requires enormous amounts of energy to contract repeatedly, so it needs many mitochondria to meet these energy demands. This is why option C is correct. Let's examine why the other options don't fit. Option A, lysosomes, are responsible for breaking down waste materials and worn-out cellular components - they're like the cell's recycling centers, not energy producers. Option B, ribosomes, synthesize proteins by translating messenger RNA. While protein synthesis requires energy, ribosomes themselves don't produce it. Option D, the Golgi apparatus, modifies and packages proteins received from the endoplasmic reticulum - it's more like a post office than a power plant. For GED Science questions about organelles, remember this key pattern: match the organelle's function to the cell's needs. High-energy cells need lots of mitochondria, cells that produce many proteins need extensive ribosomes and endoplasmic reticulum, and cells involved in detoxification have numerous lysosomes. Always connect cellular structure to cellular function - this relationship appears frequently on the exam.

Question 2

The process of photosynthesis, which converts light energy into chemical energy, occurs in which organelle?

  1. Vacuole
  2. Mitochondrion
  3. Nucleus
  4. Chloroplast (correct answer)
Explanation: When you encounter questions about cellular processes and their locations, focus on matching each organelle's structure to its specific function within the cell. Photosynthesis is the process where plants convert sunlight, carbon dioxide, and water into glucose and oxygen. This complex process requires specialized structures to capture light energy and house the chemical reactions involved. Chloroplasts are the organelles specifically designed for this job. They contain chlorophyll, the green pigment that absorbs light energy, and have internal membrane systems called thylakoids where the light-dependent reactions occur. The surrounding stroma is where carbon dioxide is converted into sugar during the light-independent reactions. Let's examine why the other options don't work: (A) Vacuoles are storage compartments that hold water, maintain cell pressure, and store various substances, but they don't perform photosynthesis. (B) Mitochondria actually do the opposite of chloroplasts—they break down glucose to release energy through cellular respiration, earning them the nickname "powerhouses of the cell." (C) The nucleus serves as the cell's control center, containing DNA and managing gene expression, but it doesn't participate in energy conversion processes. For the GED Science exam, remember that organelles have specialized functions that match their structures. Create mental connections: chloroplasts are green (chlorophyll) and make food from sunlight, while mitochondria break down food to release energy. This structure-function relationship is a recurring theme in cell biology questions.

Question 3

The series of events in Meiosis II are most similar to the events of which other process?

  1. Meiosis I
  2. Mitosis (correct answer)
  3. Interphase
  4. Fertilization
Explanation: When you encounter questions comparing cellular processes, focus on the key events: chromosome behavior, spindle formation, and cell division outcomes. Meiosis II closely mirrors mitosis in its mechanics. Both processes begin with chromosomes that consist of two sister chromatids joined at the centromere. In both, spindle fibers attach to kinetochores, chromosomes align at the cell's equator (metaphase plate), and sister chromatids separate and move to opposite poles. Finally, cytokinesis divides the cytoplasm, producing two daughter cells. The critical similarity is that sister chromatids separate during both processes. Let's examine why the other options don't match. Choice (A) Meiosis I differs fundamentally because homologous chromosome pairs separate, not sister chromatids. This creates the reduction from diploid to haploid, which doesn't happen in Meiosis II. Choice (C) Interphase involves DNA replication and cell growth, but no chromosome separation or cell division occurs. Choice (D) Fertilization is the fusion of gametes to restore the diploid chromosome number—essentially the opposite of what happens in Meiosis II. The key distinction is that Meiosis II takes haploid cells and maintains their haploid status while separating sister chromatids, just like mitosis separates sister chromatids while maintaining the original ploidy level. Study tip: Remember that Meiosis I is the "reduction division" (diploid to haploid), while Meiosis II is the "separation division" (sister chromatids apart)—making it mechanically identical to mitosis, just starting with haploid cells instead of diploid ones.

Question 4

Protein synthesis is the primary function of which small, numerous cellular structures?

  1. Lysosomes
  2. Centrioles
  3. Ribosomes (correct answer)
  4. Peroxisomes
Explanation: This question tests your knowledge of cellular organelles and their specific functions, particularly focusing on which structure is responsible for making proteins. Ribosomes are the correct answer because they are literally the protein-making factories of the cell. These small, numerous structures read the genetic instructions (mRNA) and assemble amino acids in the correct sequence to build proteins. Ribosomes can be found floating freely in the cytoplasm or attached to the endoplasmic reticulum, and both locations serve the primary function of protein synthesis. Let's examine why the other options are incorrect. Choice A, lysosomes, are membrane-bound organelles that function as the cell's digestive system, breaking down waste materials and worn-out cellular components—they don't make proteins. Choice B, centrioles, are involved in cell division and organizing the cell's microtubules, but they play no role in protein synthesis. Choice D, peroxisomes, are specialized organelles that break down fatty acids and detoxify harmful substances like hydrogen peroxide, again unrelated to protein production. When studying cellular organelles for the GED Science exam, focus on matching each structure to its primary function. Create a mental map linking ribosomes to protein synthesis, lysosomes to digestion/cleanup, and so on. Remember that ribosomes are unique because they're not membrane-bound like most other organelles, and their small, numerous nature makes them perfectly suited for the constant protein production needs of living cells.

Question 5

During which stage of mitosis do the sister chromatids separate and move towards opposite poles of the cell?

  1. Anaphase (correct answer)
  2. Metaphase
  3. Prophase
  4. Telophase
Explanation: When you encounter mitosis questions on the GED, focus on what's actually happening to the chromosomes during each phase—this is usually the key to identifying the correct stage. Anaphase is the stage where sister chromatids finally separate and move to opposite ends of the cell. Think of it as the "action phase"—the chromatids that have been paired together since DNA replication now split apart and migrate toward opposite poles, pulled by spindle fibers. This separation ensures each new cell will receive an identical copy of each chromosome. Let's examine why the other options don't fit. Option B, metaphase, is when chromosomes line up at the cell's center (the metaphase plate), but sister chromatids remain attached—no separation occurs yet. Option C, prophase, involves chromosomes condensing and becoming visible, plus the nuclear envelope breaking down, but chromatids stay together as pairs. Option D, telophase, happens after chromatid separation is complete—this is when new nuclear envelopes form around each set of separated chromosomes. The correct answer is A) Anaphase, because this is the only stage where sister chromatids actually separate and move apart. For GED mitosis questions, remember the phrase "Ana = Apart" to recall that anaphase is when chromatids move apart. Also, focus on chromosome behavior rather than other cellular changes—the movement and separation of genetic material is usually what these questions test, and it's the most reliable way to distinguish between the phases.

Question 6

The division of the cytoplasm to form two separate daughter cells, which occurs after nuclear division, is called:

  1. Interphase
  2. Karyokinesis
  3. Apoptosis
  4. Cytokinesis (correct answer)
Explanation: This question tests your knowledge of cell division terminology, specifically the phases that occur during mitosis and meiosis. Understanding the precise vocabulary used to describe different stages of cell division is crucial for biology success. The correct answer is D) Cytokinesis. This term literally means "cell movement" and refers to the physical process where the cell's cytoplasm divides to create two separate daughter cells. This happens after the nucleus has already divided and the genetic material has been distributed. During cytokinesis, a contractile ring of proteins pinches the cell membrane inward until the cell splits completely in two. Let's examine why the other options are incorrect. A) Interphase is the longest phase of the cell cycle where the cell grows and replicates its DNA, but no actual division occurs. B) Karyokinesis refers specifically to nuclear division—the process where the nucleus divides and chromosomes are separated, but the cytoplasm remains intact. This happens before cytokinesis. C) Apoptosis is programmed cell death, which is completely different from cell division—it's actually the opposite process where cells deliberately destroy themselves. Remember this sequence: karyokinesis (nuclear division) always comes first, followed by cytokinesis (cytoplasmic division). A helpful memory trick is that "cyto" refers to the cell/cytoplasm, while "karyo" refers to the nucleus. On the GED, watch for questions that test whether you can distinguish between nuclear events versus whole-cell events in division processes.

Question 7

According to one of the main principles of cell theory, what is considered the basic unit of structure and function in all known organisms?

  1. The organ
  2. The tissue
  3. The cell (correct answer)
  4. The organelle
Explanation: When you encounter questions about cell theory, you're being tested on one of biology's most fundamental principles. Cell theory consists of three main tenets that describe how all living things are organized and function. The correct answer is C because cell theory specifically states that the cell is the basic unit of structure and function in all living organisms. This principle, established in the mid-1800s by scientists like Schleiden and Schwann, means that everything living things do—from metabolism to reproduction—ultimately happens at the cellular level. Whether you're looking at a single-celled bacterium or a complex multicellular organism like a human, the cell remains the smallest unit that can carry out all the processes necessary for life. Option A is incorrect because organs are collections of different tissues working together—they're made up of many cells and represent a higher level of organization. Option B is wrong because tissues are groups of similar cells, but they're still composed of individual cells as their basic units. Option D is incorrect because organelles are structures within cells (like mitochondria or nuclei)—they're smaller components that cannot function independently as living units. For GED Science success, memorize the three principles of cell theory: all living things are made of cells, the cell is the basic unit of life, and all cells come from pre-existing cells. Questions often test whether you can distinguish between different levels of biological organization, so remember the hierarchy: organelles → cells → tissues → organs → organ systems.

Question 8

In a 2n=82n=8 cell, meiosis yields four sperm: two normal, one with 5 chromosomes, one with 3. The error occurred during

  1. meiosis II (correct answer)
  2. meiosis I
  3. S phase
  4. mitosis
Explanation: Normal sperm have 4 chromosomes, so two normal gametes mean meiosis I separated homologs correctly. A single meiosis II nondisjunction of sister chromatids gives one sperm with 5 and one with 3, while the other meiosis II division yields two normal sperm. The tempting wrong answer is meiosis I, but that would produce two sperm with 5 and two with 3, not two normal ones.

Question 9

Chromosomes are lined up single-file at the equator. This occurs during

  1. meiosis I only
  2. mitosis only
  3. meiosis II only
  4. mitosis/meiosis II (correct answer)
Explanation: In mitosis and meiosis II, individual chromosomes align singly at the metaphase plate. Meiosis I differs: homologous chromosome pairs line up together as tetrads, so they are not single-file. The tempting error is choosing meiosis I only, but that stage has paired homologs at the equator, not individual chromosomes.

Question 10

A 2n=102n=10 cell enters mitosis after S phase. At anaphase, how many chromosomes are pulled to each pole?

  1. 5
  2. 10 (correct answer)
  3. 20
  4. 40
Explanation: Since 2n=10, the cell has 10 chromosomes. S phase duplicates DNA but the chromosome number stays 10. At anaphase, sister chromatids separate, so 10 chromosomes move to each pole. The tempting wrong answer is 5, the haploid number, but anaphase separates sister chromatids, not homologous pairs.

Question 11

An animal cell completes nuclear division but cannot split into two cells. Which component is most likely defective?

  1. Spindle microtubules
  2. Intermediate filaments
  3. Actin microfilaments (correct answer)
  4. Centriole microtubules
Explanation: Because nuclear division finished, the machinery that separates chromosomes worked. Splitting the cytoplasm into two cells requires the actin microfilament contractile ring to pinch the membrane. Spindle microtubules are the tempting choice, but they act in chromosome separation during mitosis, not in the final cleavage.

Question 12

At anaphase, a drug stops spindle fibers from shortening. Which process is blocked?

  1. Condensation of chromosomes
  2. Duplication of chromosomes
  3. Sister chromatids separating
  4. Chromosomes moving to poles (correct answer)
Explanation: Spindle fibers shorten during anaphase to pull the chromosomes toward opposite poles of the cell. Blocking that shortening stops chromosome movement. The tempting wrong answer is sister chromatids separating, but separation is caused by breakdown of cohesin proteins, not by spindle fiber shortening.

Question 13

In which phase of the cell cycle does the cell replicate its DNA in preparation for division?

  1. S phase (correct answer)
  2. G1 phase
  3. G2 phase
  4. M phase
Explanation: Cell cycle questions test your understanding of the distinct phases cells go through as they grow and divide. The key is knowing what major event occurs in each phase. The S phase is specifically dedicated to DNA synthesis and replication. During this phase, the cell creates an identical copy of its entire genome, ensuring that when division occurs, each daughter cell receives a complete set of genetic information. The "S" literally stands for "synthesis," referring to DNA synthesis. This is a critical preparatory step that must happen before the cell can physically divide. Looking at the other phases: B) G1 phase occurs before DNA replication and is primarily focused on cell growth and accumulation of materials needed for replication. The cell is preparing for S phase but hasn't begun copying DNA yet. C) G2 phase happens after DNA replication is complete. During G2, the cell continues growing and produces proteins necessary for chromosome condensation and division, but DNA synthesis is already finished. D) M phase is when mitosis actually occurs—the physical separation of chromosomes and division into two daughter cells. DNA must already be replicated before this phase begins. Remember the sequence: G1 (growth and prep) → S (DNA synthesis) → G2 (more growth and prep for division) → M (actual division). When you see questions about DNA replication in the cell cycle, think "S phase for synthesis." This is one of the most fundamental concepts in cell biology and appears frequently on science exams.

Question 14

What is the final outcome of a single cell that undergoes meiosis?

  1. Two genetically identical diploid daughter cells.
  2. Four genetically unique haploid daughter cells. (correct answer)
  3. Two genetically unique diploid daughter cells.
  4. Four genetically identical diploid daughter cells.
Explanation: When you encounter questions about meiosis, focus on two key outcomes: the number of cells produced and their genetic characteristics compared to the original cell. Meiosis is a specialized type of cell division that produces gametes (sex cells like sperm and eggs). Unlike mitosis, which maintains chromosome number, meiosis reduces it by half. A single diploid cell (containing two sets of chromosomes) undergoes two consecutive divisions—meiosis I and meiosis II—resulting in four haploid cells (containing one set of chromosomes each). The genetic uniqueness comes from two processes: crossing over during prophase I, where homologous chromosomes exchange genetic material, and independent assortment, where chromosomes randomly align during metaphase I. These mechanisms ensure each of the four daughter cells has a different genetic combination. Choice A is incorrect because meiosis produces four cells, not two, and the cells are haploid, not diploid. Choice C is wrong because while the cells would be genetically unique, meiosis produces four cells, not two, and they're haploid, not diploid. Choice D incorrectly suggests the cells are genetically identical—this would be true for mitosis but not meiosis, which specifically creates genetic diversity. The correct answer is B: four genetically unique haploid daughter cells. For GED questions about cell division, remember this pattern: mitosis produces two identical diploid cells (for growth and repair), while meiosis produces four unique haploid cells (for reproduction). The number four and genetic uniqueness are hallmarks of meiosis.

Question 15

Which organelle contains digestive enzymes and is responsible for breaking down cellular waste and foreign particles?

  1. Golgi apparatus
  2. Endoplasmic reticulum
  3. Vacuole
  4. Lysosome (correct answer)
Explanation: When you encounter questions about cellular organelles, focus on matching each structure's specific function to what the question is asking for. This question specifically asks about an organelle that contains digestive enzymes and breaks down waste and foreign particles. Lysosomes are the cell's recycling centers and cleanup crew. They contain powerful digestive enzymes that break down worn-out organelles, cellular waste products, and harmful substances that enter the cell. Think of them as the cell's garbage disposal and recycling system rolled into one. These membrane-bound sacs are particularly abundant in cells that do a lot of "cleaning work," like white blood cells that engulf bacteria. Let's examine why the other options don't fit: The Golgi apparatus (A) is the cell's shipping and packaging center - it modifies, packages, and ships proteins from the endoplasmic reticulum, but doesn't contain digestive enzymes. The endoplasmic reticulum (B) is involved in protein synthesis (rough ER) and lipid production (smooth ER), not digestion of waste. Vacuoles (C) are storage compartments that hold water, ions, and other materials, but they don't contain digestive enzymes for breaking down waste. The correct answer is D) Lysosome. Study tip: Remember the organelles by their key functions: lysosomes = digestion and cleanup, Golgi = packaging and shipping, ER = protein/lipid production, vacuoles = storage. On the GED, organelle questions often test whether you can match structure to function, so memorize each organelle's primary job.

Question 16

Which organelle functions to modify, sort, and package proteins and lipids for secretion or delivery to other organelles?

  1. Nucleolus
  2. Smooth endoplasmic reticulum
  3. Ribosome
  4. Golgi apparatus (correct answer)
Explanation: When you encounter questions about cellular organelles, focus on each organelle's specific function within the cell's protein production and transport system. Think of the cell as a factory with specialized departments handling different stages of protein processing. The Golgi apparatus serves as the cell's "shipping and receiving department." After proteins are synthesized by ribosomes and initially processed in the endoplasmic reticulum, they move to the Golgi apparatus. Here, proteins and lipids undergo final modifications, get sorted based on their destinations, and are packaged into vesicles for transport. The Golgi acts like a post office, adding "address labels" (chemical tags) that direct proteins to their proper locations—whether that's secretion outside the cell, incorporation into membranes, or delivery to other organelles. Looking at the wrong answers: (A) The nucleolus specifically makes ribosomal RNA and assembles ribosomes—it doesn't handle protein modification or packaging. (B) The smooth endoplasmic reticulum synthesizes lipids and detoxifies substances but doesn't perform the sorting and packaging functions described. (C) Ribosomes manufacture proteins by translating mRNA, but they don't modify, sort, or package the finished products. For GED Science questions about organelles, remember that each structure has a distinct role in the cellular assembly line. The Golgi apparatus is always your answer when you see "modify," "sort," and "package" together, especially regarding proteins destined for secretion. Think of it as the final quality control and shipping center of the cell.

Question 17

Nerve cells, or neurons, possess long, thin extensions called axons. How does this specialized structure relate to the cell's function?

  1. It allows for the transmission of signals over long distances in the body. (correct answer)
  2. It increases the surface area for absorbing nutrients from the body.
  3. It provides the structural support needed for muscle contraction.
  4. It stores large amounts of energy in the form of glycogen for later use.
Explanation: When you encounter questions about cell structure and function, focus on how the physical characteristics of cellular components directly support their specific roles. This structure-function relationship is a fundamental principle in biology. Axons are remarkably long extensions of nerve cells that can stretch from your spinal cord all the way to your toes—sometimes over three feet long. This elongated structure is perfectly designed for the neuron's primary job: rapidly transmitting electrical and chemical signals across great distances in your body. Think of axons as biological cables that carry messages from your brain to distant body parts and back again. Without these long extensions, your nervous system couldn't coordinate complex activities like walking or quickly pulling your hand away from something hot. Now let's examine why the other options miss the mark. Option B incorrectly suggests axons are for nutrient absorption—but neurons get nutrients from surrounding support cells, not through their axons. Option C confuses nerve cells with muscle cells; while neurons signal muscles to contract, they don't provide structural support for the contraction itself. Option D misrepresents axons as energy storage sites, but neurons store very little glycogen and certainly not in their axons, which are primarily composed of the cellular machinery needed for signal transmission. For GED Science success, remember that biological structures are shaped by their functions. When you see questions about specialized cell parts, always ask yourself: "What job does this structure need to do, and how does its shape help it do that job effectively?"

Question 18

A cell in the pancreas that produces a large amount of lipid-based hormones would be expected to have a well-developed:

  1. Rough endoplasmic reticulum
  2. Mitochondrion
  3. Smooth endoplasmic reticulum (correct answer)
  4. Lysosome
Explanation: When you encounter questions about cellular organelles and hormone production, focus on matching the organelle's structure to its specific function in the cell. Lipid-based hormones like steroid hormones require specialized cellular machinery for their synthesis. The smooth endoplasmic reticulum (smooth ER) is perfectly designed for this task because it contains the enzymes necessary for lipid synthesis and steroid hormone production. Its smooth surface (lacking ribosomes) allows it to focus entirely on these synthetic processes. Pancreatic cells that produce large amounts of lipid-based hormones would need an extensively developed smooth ER to meet this high production demand. Let's examine why the other options don't fit: (A) Rough endoplasmic reticulum is specialized for protein synthesis due to its ribosome-studded surface, not lipid-based hormone production. (B) Mitochondrion generates ATP energy for cellular processes but doesn't directly synthesize hormones, though it does provide the energy needed for synthesis. (D) Lysosome functions in cellular digestion and waste removal, which is unrelated to hormone production. The correct answer is (C) because smooth endoplasmic reticulum is the organelle specifically equipped with the enzymatic machinery needed for lipid and steroid hormone synthesis. Remember this pattern: organelle questions on the GED often test whether you can match structure to function. Smooth ER = lipid synthesis, rough ER = protein synthesis, mitochondria = energy production, and lysosomes = digestion and cleanup. Know these core functions to quickly eliminate wrong answers.

Question 19

What is the key difference that distinguishes prokaryotic cells from eukaryotic cells?

  1. Prokaryotic cells have a cell wall, while eukaryotic cells do not.
  2. Prokaryotic cells contain cytoplasm, while eukaryotic cells do not.
  3. Prokaryotic cells use ribosomes for protein synthesis, while eukaryotic cells do not.
  4. Prokaryotic cells lack a true nucleus and membrane-bound organelles. (correct answer)
Explanation: Cell structure questions on the GED test your understanding of fundamental differences between the two main types of cells. The defining characteristic that separates prokaryotes from eukaryotes is how their genetic material is organized and whether they have specialized internal compartments. Prokaryotic cells (like bacteria) have their DNA freely floating in the cytoplasm without being enclosed in a membrane-bound nucleus. They also lack other membrane-bound organelles like mitochondria, endoplasmic reticulum, or Golgi apparatus. Eukaryotic cells (like plant, animal, and fungal cells) have their DNA contained within a true nucleus surrounded by a nuclear membrane, plus various membrane-bound organelles that perform specialized functions. Looking at the wrong answers: Choice A is incorrect because many eukaryotic cells do have cell walls (like plants and fungi), while some prokaryotes lack them. Choice B is wrong because both cell types contain cytoplasm - the gel-like substance that fills the cell. Choice C is false because both prokaryotes and eukaryotes use ribosomes for protein synthesis, though the ribosomes differ slightly in size and structure. Choice D correctly identifies the key distinction: prokaryotic cells lack a true nucleus and membrane-bound organelles. Study tip: Remember "PRO-karyotic = NO nucleus" - the prefix "pro" means "before," referring to cells that evolved before the nucleus developed. When you see cell classification questions, always think about nuclear organization first, as this is the most fundamental difference between these cell types.

Question 20

One of the three main principles of modern cell theory states that all cells arise from pre-existing cells. This principle directly refutes which historical scientific idea?

  1. The theory of evolution
  2. The law of independent assortment
  3. The concept of spontaneous generation (correct answer)
  4. The process of sexual reproduction
Explanation: When you encounter questions about cell theory, focus on the three fundamental principles: all living things are made of cells, cells are the basic unit of life, and all cells come from pre-existing cells. This third principle was revolutionary because it directly challenged a widespread belief about how life could begin. The concept of spontaneous generation held that living organisms could arise from non-living matter under certain conditions. People believed maggots spontaneously appeared in rotting meat, mice emerged from grain stores, and microorganisms developed from nothing in broths. Scientists like Francesco Redi and Louis Pasteur conducted controlled experiments that disproved this idea, showing that life only comes from existing life. This work directly supported cell theory's principle that cells arise only from pre-existing cells through processes like cell division. Looking at the wrong answers: Choice A is incorrect because evolution describes how species change over time through natural selection, which actually works alongside cell theory rather than contradicting it. Choice B refers to Mendel's law about how different genes are inherited independently, which is unrelated to cell origins. Choice D describes sexual reproduction, a biological process that involves existing cells combining to create new organisms—this supports rather than contradicts the idea that cells come from pre-existing cells. For GED Science questions about historical scientific concepts, remember that many involved replacing old misconceptions with evidence-based understanding. Spontaneous generation versus cell theory is a classic example of how careful experimentation overturned long-held but incorrect beliefs about life's origins.