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GA Milestones Biology EOC study materials
GA Milestones Biology EOC study resources

GA Milestones Biology EOC practice questions

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Question 1Biological inquiry and interpretation of evidence

A researcher predicts that tomato plants given a nitrogen-enriched fertilizer will produce more fruit than plants given a standard fertilizer. In this study, the amount of fruit produced is best described as which of the following?

  1. The hypothesis
  2. A controlled variable
  3. The dependent variable Correct answer.
  4. The independent variable

Explanation

The dependent variable is the measured outcome that responds to the manipulation, which here is fruit yield. The fertilizer type is the factor the researcher deliberately changes, so it is the independent variable rather than the measured result.

Question 2Biological inquiry and interpretation of evidence

A student measures the mass of the same sample five times and obtains nearly identical values, but the balance was never zeroed and reads 2.0 g too high. How should these measurements be described?

  1. Both accurate and precise
  2. Precise but not accurate Correct answer.
  3. Accurate but not precise
  4. Neither accurate nor precise

Explanation

Precision refers to how closely repeated measurements agree with one another, while accuracy refers to how close they are to the true value. Because the readings cluster tightly but are systematically offset by the unzeroed balance, they are precise but inaccurate.

Question 3Biological inquiry and interpretation of evidence

Which of the following best distinguishes a scientific hypothesis from a scientific theory?

  1. A hypothesis is a testable proposed explanation, while a theory is a well-supported explanatory framework built from extensive evidence Correct answer.
  2. A hypothesis is always correct once tested, while a theory remains an untested guess
  3. A hypothesis is a broad framework, while a theory is a single testable prediction
  4. A hypothesis applies only to biology, while a theory applies only to physics

Explanation

In science, a hypothesis is a testable proposed explanation for a specific observation, whereas a theory is a broad, well-substantiated explanation supported by many lines of evidence. The common usage of theory as a mere guess is incorrect in scientific contexts.

Question 4Biological inquiry and interpretation of evidence

A scientist repeats an experiment several times and obtains consistent results. Which conclusion is most justified?

  1. The findings are reliable and reproducible under the tested conditions Correct answer.
  2. The results now apply to all organisms everywhere
  3. The hypothesis has been proven true beyond any doubt
  4. The experiment has no remaining sources of error

Explanation

Reproducible results indicate reliability, meaning the procedure yields consistent outcomes under the tested conditions. Science does not establish absolute proof, and replication does not eliminate error or guarantee universal applicability.

Question 5Biological inquiry and interpretation of evidence

A graph plots plant height on the y-axis against days of growth on the x-axis. Which statement correctly identifies the placement of these variables?

  1. Days of growth is the independent variable on the x-axis, and height is the dependent variable on the y-axis Correct answer.
  2. Both variables are dependent and should share the x-axis
  3. Days of growth is the dependent variable because it is measured over time
  4. Height is the independent variable on the y-axis, and days of growth is the dependent variable on the x-axis

Explanation

By convention, the independent variable is placed on the x-axis and the dependent variable on the y-axis. Height responds to elapsed time, so time is independent and height is dependent.

Question 6Biological inquiry and interpretation of evidence

A student notices that mold grows on bread left in a warm, humid place but not on bread stored in a dry, cool place. Which of the following is the most appropriate next step in the scientific process?

  1. Formulate a testable hypothesis and design a controlled experiment to test it Correct answer.
  2. Conclude immediately that warmth and moisture cause mold growth
  3. Publish the observation as a confirmed scientific law
  4. Discard the observation because it was not made in a laboratory

Explanation

An observation generates questions that should be framed as a testable hypothesis and examined through a controlled experiment. Reaching a firm causal conclusion from a single uncontrolled observation is premature.

Question 7Biochemistry

Which property of water is most directly responsible for its ability to moderate temperature in living organisms and large bodies of water?

  1. Its low specific heat
  2. Its inability to form hydrogen bonds
  3. Its nonpolar covalent bonds
  4. Its high specific heat Correct answer.

Explanation

Water has a high specific heat because hydrogen bonds must absorb or release substantial energy before water molecules change temperature. This allows water and water-rich organisms to resist large temperature swings, helping maintain homeostasis.

Question 8Cell structure, membranes and division

Which structure is found in a typical plant cell but NOT in a typical animal cell?

  1. Mitochondrion
  2. Nucleus
  3. Ribosome
  4. Cell wall made of cellulose Correct answer.

Explanation

Plant cells have a rigid cell wall composed primarily of cellulose that surrounds the plasma membrane, providing structural support. Animal cells lack a cell wall, relying on the cytoskeleton and extracellular matrix instead.

Question 9Genetics, inheritance and molecular information

Meiosis differs from mitosis in that meiosis produces

  1. Two genetically identical diploid cells
  2. One diploid cell with double the chromosomes
  3. Two haploid cells identical to the parent
  4. Four genetically varied haploid cells Correct answer.

Explanation

Meiosis consists of two divisions that produce four haploid gametes, each with half the chromosome number of the parent. Crossing over and independent assortment generate genetic variation, distinguishing meiosis from the identical-diploid products of mitosis.

Question 10Metabolism

An enzyme lowers the activation energy of a reaction. Which statement best describes how this affects the reaction?

  1. It increases the reaction rate without being consumed in the reaction Correct answer.
  2. It changes the overall free-energy difference between reactants and products
  3. It supplies the energy needed to make an endergonic reaction exergonic
  4. It permanently binds to the product to stop the reaction

Explanation

Enzymes are biological catalysts that lower activation energy, speeding up reactions without being consumed. They do not change the net free-energy difference (delta G) between reactants and products; they only make the reaction reach equilibrium faster.

Question 11Physiology

Which feature allows a steroid hormone to pass directly through the plasma membrane?

  1. Its lipid (hydrophobic) nature lets it dissolve through the phospholipid bilayer Correct answer.
  2. Its large size lets it push proteins aside
  3. Its negative charge attracts it to the membrane interior
  4. Its attachment to a carbohydrate tag opens a channel

Explanation

Steroid hormones are lipid-soluble (hydrophobic), so they can dissolve through the hydrophobic interior of the phospholipid bilayer without a transport protein. Once inside, they typically bind intracellular receptors that act on the DNA to regulate gene expression.

Question 12Ecology

In an energy pyramid, only about 10 percent of the energy at one trophic level is transferred to the next. Most of the remaining energy is

  1. Converted directly into new biomass at the next level
  2. Lost as heat, largely through cellular respiration and metabolic processes Correct answer.
  3. Stored permanently in the soil
  4. Recycled back to producers as light energy

Explanation

At each trophic level, organisms use most of the energy they consume for metabolism and lose much of it as heat through cellular respiration. Only about 10 percent is stored as biomass available to the next level, which limits food chain length.

Question 13Evolution

Which of the following is a necessary condition for natural selection to occur in a population?

  1. All individuals are genetically identical
  2. Heritable variation exists and affects survival or reproduction Correct answer.
  3. The environment never changes
  4. Every individual produces the same number of offspring

Explanation

Natural selection requires heritable variation among individuals and differences in reproductive success linked to that variation. Individuals with advantageous heritable traits leave more offspring, shifting the population's traits over generations.

Question 14Cell structure, membranes and division

Which organelle is the primary site of ATP production through aerobic cellular respiration in a eukaryotic cell?

  1. Mitochondrion Correct answer.
  2. Ribosome
  3. Golgi apparatus
  4. Lysosome

Explanation

The mitochondrion carries out the citric acid cycle and oxidative phosphorylation, producing most of a cell's ATP. Its folded inner membrane (cristae) holds the electron transport chain. This is why mitochondria are called the powerhouse of the cell.

Question 15Cell structure, membranes and division

A student observes a cell under a microscope and notes that it has no nucleus and no membrane-bound organelles. The cell is most likely a

  1. prokaryotic cell Correct answer.
  2. plant cell
  3. animal cell
  4. fungal cell

Explanation

Prokaryotic cells, such as bacteria, lack a nucleus and membrane-bound organelles; their DNA is in a nucleoid region. Eukaryotic cells (plant, animal, fungal) all contain a true nucleus and membrane-bound organelles. The absence of these features identifies the cell as prokaryotic.

Question 16Cell structure, membranes and division

Which feature of the cell membrane best explains why it is described as a fluid mosaic?

  1. Phospholipids and embedded proteins can move laterally within the bilayer Correct answer.
  2. It is composed of a rigid layer of cellulose
  3. It is made entirely of a single type of protein
  4. It is completely impermeable to all molecules

Explanation

The fluid mosaic model describes the membrane as a flexible phospholipid bilayer with various proteins, cholesterol, and carbohydrates embedded in it. The components can drift laterally, giving the membrane its fluid quality, while the mix of molecules creates the mosaic pattern. This structure allows selective permeability.

Question 17Cell structure, membranes and division

A plant cell is placed in pure distilled water. What will most likely happen to the cell?

  1. Water will move into the cell, increasing turgor pressure against the cell wall Correct answer.
  2. Water will rush out of the cell, causing it to shrivel
  3. The cell will burst immediately because it has no wall
  4. No net movement of water will occur

Explanation

Distilled water is hypotonic to the cell's cytoplasm, so water moves into the cell by osmosis. The rigid cell wall resists expansion, building turgor pressure that keeps the plant firm. The wall prevents the cell from bursting.

Question 18Cell structure, membranes and division

Which process moves molecules across a cell membrane from a region of lower concentration to a region of higher concentration?

  1. Active transport Correct answer.
  2. Simple diffusion
  3. Osmosis
  4. Facilitated diffusion

Explanation

Active transport moves substances against their concentration gradient, from low to high concentration, and therefore requires energy from ATP. The sodium-potassium pump is a classic example. Passive processes only move substances down their gradient.

Question 19Cell structure, membranes and division

Which organelle in plant cells captures light energy to produce glucose during photosynthesis?

  1. Chloroplast Correct answer.
  2. Mitochondrion
  3. Vacuole
  4. Nucleus

Explanation

Chloroplasts contain chlorophyll, the green pigment that absorbs light energy used to convert carbon dioxide and water into glucose. They are found in plant cells and some protists. Photosynthesis takes place in the thylakoid membranes and stroma of the chloroplast.

Question 20Cell structure, membranes and division

Which of the following is a characteristic shared by all living organisms?

  1. They are made of one or more cells Correct answer.
  2. They all carry out photosynthesis
  3. They all have a backbone
  4. They all live on land

Explanation

All living things are composed of one or more cells, which is the basic unit of life according to cell theory. Other shared characteristics include using energy, responding to stimuli, growing, and reproducing. Not all organisms photosynthesize, have backbones, or live on land.

Question 21Cell structure, membranes and division

Which statement is a principle of the cell theory?

  1. All living things are made of cells, and all cells come from pre-existing cells Correct answer.
  2. Cells can form spontaneously from nonliving matter
  3. Only plants are made of cells
  4. Cells are the largest structures in an organism

Explanation

The cell theory states that all living things are composed of cells, the cell is the basic unit of structure and function, and all cells arise from pre-existing cells. It is a foundational concept in biology developed by Schleiden, Schwann, and Virchow. It rejects the idea of spontaneous generation.

Question 22Cell structure, membranes and division

Which structure is found in plant cells but NOT in animal cells?

  1. Cell wall Correct answer.
  2. Cell membrane
  3. Nucleus
  4. Mitochondrion

Explanation

Plant cells have a rigid cell wall made of cellulose surrounding the cell membrane, which provides support and shape. Animal cells lack a cell wall. Both cell types share a cell membrane, nucleus, and mitochondria.

Question 23Cell structure, membranes and division

Which organelle is responsible for assembling amino acids into proteins by reading messenger RNA?

  1. Ribosome Correct answer.
  2. Vacuole
  3. Lysosome
  4. Centriole

Explanation

Ribosomes are the sites of protein synthesis, where they read mRNA codons and link amino acids into polypeptide chains. They can float freely in the cytoplasm or attach to the rough endoplasmic reticulum. Ribosomes are found in both prokaryotic and eukaryotic cells.

Question 24Cell structure, membranes and division

Which type of microscope would a student need to view the detailed internal structures of a cell's organelles at very high magnification?

  1. Electron microscope Correct answer.
  2. Hand lens
  3. Light microscope at low power
  4. Telescope

Explanation

Electron microscopes use beams of electrons rather than light, allowing magnifications high enough to reveal fine details of organelles and other tiny structures. Standard light microscopes have much lower resolving power. Electron microscopes are essential tools in modern cell biology.

Question 25Cell structure, membranes and division

The nucleus controls cell activities primarily because it contains

  1. the cell's DNA, which carries instructions for making proteins Correct answer.
  2. all of the cell's stored energy
  3. the digestive enzymes of the cell
  4. the structures that perform photosynthesis

Explanation

The nucleus houses the cell's DNA, which contains the genetic instructions for building proteins that carry out and regulate cellular activities. By controlling which proteins are made, the nucleus directs the function of the entire cell. It is bounded by a nuclear envelope with pores.

Question 26Cell structure, membranes and division

Which statement best describes how viruses differ from living cells?

  1. Viruses are not made of cells and must use a host cell to reproduce Correct answer.
  2. Viruses contain mitochondria for producing their own energy
  3. Viruses reproduce by mitosis on their own
  4. Viruses carry out photosynthesis

Explanation

Viruses are not cells; they consist of genetic material surrounded by a protein coat and cannot reproduce on their own. They must infect a living host cell and hijack its machinery to make new viruses. This is why scientists debate whether viruses are truly alive.

Question 27Cell structure, membranes and division

A cell placed in a hypertonic solution (higher solute concentration outside the cell) will most likely

  1. lose water and shrink Correct answer.
  2. gain water and swell
  3. remain exactly the same size
  4. burst from too much water entering

Explanation

In a hypertonic solution, the surrounding fluid has a higher solute concentration than the cytoplasm, so water moves out of the cell by osmosis. The cell loses water and shrinks, a process called crenation in animal cells or plasmolysis in plant cells. Water always moves toward the higher solute concentration.

Question 28Cell structure, membranes and division

Which process allows a single-celled organism such as an amoeba to engulf and take in large food particles?

  1. Endocytosis Correct answer.
  2. Osmosis
  3. Diffusion
  4. Transcription

Explanation

Endocytosis is the process in which the cell membrane surrounds and engulfs large particles or fluids, bringing them into the cell within a vesicle. Amoebas use this process, called phagocytosis when it involves solid food, to obtain nutrients. It requires energy because it moves large materials.

Question 29Biochemistry

Enzymes speed up biochemical reactions in cells primarily by

  1. lowering the activation energy required for the reaction Correct answer.
  2. increasing the temperature of the cell
  3. adding extra energy to the reactants
  4. permanently binding to and consuming the substrate

Explanation

Enzymes are biological catalysts that lower the activation energy needed for a reaction to proceed, allowing it to occur faster at body temperature. They bind substrates at their active site but are not consumed and can be reused. This makes cellular reactions efficient.

Question 30Biochemistry

Which class of biological macromolecule serves as the main source of quick energy and includes monosaccharides such as glucose?

  1. Carbohydrates Correct answer.
  2. Proteins
  3. Lipids
  4. Nucleic acids

Explanation

Carbohydrates are made of carbon, hydrogen, and oxygen and include sugars like glucose, which cells break down rapidly for energy. Their monomers are monosaccharides. Polysaccharides such as starch and glycogen store this energy.

Question 31Biochemistry

What are the monomers (building blocks) that link together to form proteins?

  1. Amino acids Correct answer.
  2. Nucleotides
  3. Fatty acids
  4. Monosaccharides

Explanation

Proteins are polymers of amino acids joined by peptide bonds. There are 20 different amino acids, and their sequence determines the protein's folding and function. The order is coded by genes in DNA.

Question 32Biochemistry

An enzyme stops functioning after the cell's environment becomes very acidic. The most likely explanation is that the enzyme has

  1. been denatured, changing the shape of its active site Correct answer.
  2. been converted into a different enzyme
  3. permanently bonded to its product
  4. increased its reaction rate

Explanation

Extreme pH disrupts the bonds that maintain an enzyme's three-dimensional shape, a process called denaturation. When the active site changes shape, the substrate no longer fits and the enzyme cannot catalyze the reaction. Each enzyme has an optimal pH and temperature range.

Question 33Biochemistry

During photosynthesis, which two raw materials are used to produce glucose and oxygen?

  1. Carbon dioxide and water Correct answer.
  2. Oxygen and glucose
  3. Nitrogen and water
  4. Carbon dioxide and oxygen

Explanation

Photosynthesis uses carbon dioxide and water, along with light energy, to produce glucose and release oxygen. The overall equation is 6CO2 + 6H2O + light energy yields C6H12O6 + 6O2. This process converts light energy into stored chemical energy.

Question 34Biochemistry

Cellular respiration and photosynthesis are described as complementary processes because

  1. the products of one process are the reactants of the other Correct answer.
  2. both processes occur only in animal cells
  3. both processes release oxygen as a waste product
  4. neither process involves the transfer of energy

Explanation

Photosynthesis produces glucose and oxygen, which are the reactants of cellular respiration, while respiration produces carbon dioxide and water, the reactants of photosynthesis. This cycling of matter links the two processes. Together they move carbon and energy through ecosystems.

Question 35Biochemistry

Water is essential to living cells largely because its polarity makes it an excellent

  1. solvent for many substances Correct answer.
  2. source of chemical energy
  3. gas at room temperature
  4. barrier that blocks all chemical reactions

Explanation

Because water molecules are polar, with partial positive and negative charges, they dissolve many ionic and polar substances, earning water the title of the universal solvent. This property allows water to transport nutrients and serve as the medium for cellular reactions. Polarity also gives water cohesion and a high heat capacity.

Question 36Biochemistry

Which type of macromolecule includes fats, oils, and steroids and is a major component of cell membranes?

  1. Lipids Correct answer.
  2. Carbohydrates
  3. Proteins
  4. Nucleic acids

Explanation

Lipids include fats, oils, waxes, and steroids, and the phospholipid bilayer is the structural foundation of cell membranes. Lipids store energy efficiently and are generally nonpolar and insoluble in water. They are built largely from fatty acids and glycerol.

Question 37Biochemistry

In the absence of oxygen, muscle cells can still produce a small amount of ATP through a process that also produces lactic acid. This process is called

  1. anaerobic respiration (fermentation) Correct answer.
  2. photosynthesis
  3. transpiration
  4. aerobic respiration

Explanation

When oxygen is scarce, cells use fermentation, a form of anaerobic respiration, to produce ATP. In human muscle cells, this produces lactic acid, which can cause muscle fatigue. Fermentation yields far less ATP than aerobic respiration but allows energy production to continue.

Question 38Biochemistry

The energy currency that cells use to power most cellular activities is

  1. ATP (adenosine triphosphate) Correct answer.
  2. DNA
  3. glucose stored in the nucleus
  4. carbon dioxide

Explanation

ATP, adenosine triphosphate, stores and releases energy through its phosphate bonds and serves as the immediate energy source for most cellular work. When a phosphate group is removed, energy is released for processes such as active transport and muscle contraction. Cellular respiration regenerates ATP from glucose.

Question 39Biochemistry

Where does the light-dependent stage of photosynthesis take place within the chloroplast?

  1. The thylakoid membranes Correct answer.
  2. The stroma
  3. The outer membrane only
  4. The cell wall

Explanation

The light-dependent reactions occur in the thylakoid membranes, where chlorophyll absorbs light and water is split to release oxygen, producing ATP and NADPH. The light-independent reactions (Calvin cycle) then occur in the stroma. This division separates the two stages of photosynthesis.

Question 40Biochemistry

A scientist measures the rate of photosynthesis in a plant as light intensity increases. The rate rises and then levels off. This leveling off most likely occurs because

  1. another factor, such as carbon dioxide concentration, has become limiting Correct answer.
  2. light can no longer be absorbed by any pigment
  3. the plant has stopped respiring
  4. water has become unlimited

Explanation

As light intensity rises, the rate of photosynthesis increases until another resource becomes the limiting factor, such as carbon dioxide concentration or temperature. Once that factor limits the reaction, adding more light no longer increases the rate. This illustrates the concept of limiting factors.

Question 41Biochemistry

In which organelle does the Calvin cycle (the light-independent reactions of photosynthesis) take place?

  1. The stroma of the chloroplast Correct answer.
  2. The cristae of the mitochondrion
  3. The nucleolus
  4. The ribosome

Explanation

The Calvin cycle, also called the light-independent reactions, occurs in the stroma, the fluid-filled space inside the chloroplast surrounding the thylakoids. There, carbon dioxide is fixed into sugar using ATP and NADPH made in the light reactions. The thylakoids handle the light-dependent reactions.

Question 42Biochemistry

Which of the following correctly lists the carbohydrate, its monomer, and a storage example?

  1. Carbohydrate built from glucose monomers; starch stores energy in plants Correct answer.
  2. Carbohydrate built from amino acids; starch stores energy in plants
  3. Carbohydrate built from nucleotides; glycogen stores energy in animals
  4. Carbohydrate built from fatty acids; cellulose stores energy in animals

Explanation

Carbohydrates are polymers of monosaccharides such as glucose. Plants store excess glucose as starch, while animals store it as glycogen. Cellulose, also made of glucose, provides structural support in plant cell walls.

Question 43Biochemistry

During cellular respiration, glucose is broken down in the presence of oxygen to release energy. Which are the main waste products of this aerobic process?

  1. Carbon dioxide and water Correct answer.
  2. Oxygen and glucose
  3. Nitrogen and ammonia
  4. Light and heat only

Explanation

Aerobic cellular respiration breaks down glucose using oxygen and produces carbon dioxide and water as waste products, along with ATP. The overall reaction is C6H12O6 + 6O2 yields 6CO2 + 6H2O + energy. These products are the reactants of photosynthesis, linking the two processes.

Question 44Biochemistry

A plant is unable to produce a functional enzyme needed for chlorophyll production due to a gene mutation. Which process will be most directly affected?

  1. Photosynthesis Correct answer.
  2. Cellular respiration in the roots
  3. DNA replication
  4. Active transport across membranes

Explanation

Chlorophyll is the pigment that absorbs light energy for photosynthesis, so a defect in chlorophyll production directly impairs the plant's ability to make food through photosynthesis. This connects a genetic change to a biochemical process. Without chlorophyll, the plant cannot capture light energy effectively.

Question 45Genetics, inheritance and molecular information

Which statement correctly describes the relationship between DNA, genes, and chromosomes?

  1. A chromosome is made of DNA, and a gene is a segment of DNA that codes for a trait Correct answer.
  2. A gene is made of many chromosomes joined together
  3. DNA is found only outside of chromosomes
  4. A chromosome is a single gene with no DNA

Explanation

DNA is the molecule that stores genetic information, a gene is a specific segment of DNA that codes for a protein or trait, and a chromosome is a long, coiled strand of DNA wrapped around proteins. Genes are located along chromosomes. Humans have 23 pairs of chromosomes.

Question 46Genetics, inheritance and molecular information

In a DNA molecule, the nitrogen base adenine always pairs with

  1. thymine Correct answer.
  2. guanine
  3. cytosine
  4. uracil

Explanation

In DNA, complementary base pairing follows specific rules: adenine pairs with thymine, and cytosine pairs with guanine. These pairs are held together by hydrogen bonds between the two strands. This pairing allows DNA to be copied accurately during replication.

Question 47Genetics, inheritance and molecular information

In pea plants, the allele for tall (T) is dominant over the allele for short (t). A cross between two heterozygous tall plants (Tt x Tt) is expected to produce what ratio of tall to short offspring?

  1. 3 tall : 1 short Correct answer.
  2. 1 tall : 1 short
  3. All tall
  4. 1 tall : 3 short

Explanation

A Tt x Tt cross produces offspring in genotype ratio 1 TT : 2 Tt : 1 tt. Because T is dominant, TT and Tt plants are tall and only tt plants are short, giving a 3:1 phenotype ratio. This is the classic monohybrid cross result.

Question 48Genetics, inheritance and molecular information

During which phase of mitosis do sister chromatids separate and move toward opposite poles of the cell?

  1. Anaphase Correct answer.
  2. Prophase
  3. Metaphase
  4. Telophase

Explanation

In anaphase, the sister chromatids are pulled apart by spindle fibers and move to opposite poles of the cell. This ensures each daughter cell receives an identical set of chromosomes. Mitosis produces two genetically identical diploid cells.

Question 49Genetics, inheritance and molecular information

How does meiosis differ from mitosis?

  1. Meiosis produces four haploid cells, while mitosis produces two diploid cells Correct answer.
  2. Meiosis produces two diploid cells, while mitosis produces four haploid cells
  3. Both processes produce genetically identical diploid cells
  4. Meiosis occurs in body cells, while mitosis occurs only in gametes

Explanation

Meiosis involves two rounds of division and produces four genetically varied haploid gametes, halving the chromosome number. Mitosis is a single division producing two diploid cells genetically identical to the parent. Meiosis maintains chromosome number across generations through fertilization.

Question 50Genetics, inheritance and molecular information

A change in the sequence of nitrogen bases in a gene is called a

  1. mutation Correct answer.
  2. translation
  3. transcription
  4. replication

Explanation

A mutation is any change in the DNA base sequence, which can be caused by errors in replication or by mutagens such as radiation. Mutations may be harmful, beneficial, or neutral, and they are the ultimate source of new genetic variation. Only mutations in gametes are passed to offspring.