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Unit 1: The Science of Life & Unit 2: Basic Chemistry (Part 1)

Total questions: 143

Worksheet time: 1hrs 12mins

Name
Class
Date
1.

Which step usually comes first in a scientific investigation?

a)

Observation of something happens

b)

Data collection after results

c)

Conclusion is written first

d)

Experiment and testing begin

2.

What is a hypothesis?

a)

A proven scientific law

b)

A testable possible explanation

c)

A description of equipment used

d)

A list of final results

3.

Which choice shows the best order of investigation steps?

a)

Observation → Question → Hypothesis → Experiment

b)

Experiment → Data → Question → Conclusion

c)

Question → Conclusion → Experiment → Observation

d)

Hypothesis → Conclusion → Data → Question

4.

Biology is mainly the study of what?

a)

Rocks and earth layers

b)

Stars and space objects

c)

Weather and climate patterns

d)

Life and living things

5.

A theory is best described as which statement?

a)

A tool scientists use

b)

A unifying explanation

c)

A guess with no testing

d)

A single experiment

6.

Which is one characteristic of life?

a)

All living things are made of cells

b)

Living things never change

c)

Living things need no energy

d)

Living things have no DNA

7.

Which characteristic matches homeostasis?

a)

Using energy to grow

b)

Maintaining stable internal conditions

c)

Dividing into new cell types

d)

Responding to physical stimuli

8.

What does reproduction involve for living things?

a)

Organisms avoid any change

b)

Energy is never used to grow

c)

Cells stop dividing forever

d)

Genes act as the blueprint for life

9.

Which statement describes growth and development?

a)

DNA is not needed for cells

b)

Organisms cannot respond to stimuli

c)

Living things never change over time

d)

Cells divide and turn into different types

10.

Which phrase describes evolution?

a)

Instant change in one day

b)

Only chemical changes happen

c)

Experience change over time

d)

No change through generations

11.

Organic molecules are mainly made from which element?

a)

Oxygen is always the base

b)

Nitrogen builds every part

c)

Carbon is the key element

d)

Hydrogen forms all parts

12.

An atom contains which three particles?

a)

Energy, matter, light

b)

Carbon, oxygen, nitrogen

c)

Cells, genes, proteins

d)

Protons, neutrons, electrons

13.

In a sodium atom, how many electrons are present if there are 11 protons?

a)

Nine electrons match

b)

Ten electrons remain

c)

Twelve electrons stay

d)

Eleven electrons balance

14.

How many neutrons are in a common sodium atom?

a)

Fourteen neutrons present

b)

Eight neutrons present

c)

Twelve neutrons present

d)

Ten neutrons present

15.

What is an element?

a)

A molecule with several parts

b)

A substance that cannot be broken down

c)

A material made of many atoms

d)

A substance broken down easily

16.

What are chemical symbols like Cl, Na, and Fe?

a)

Nicknames for compounds

b)

Pictures for reactions

c)

Codes for laboratory tools

d)

Abbreviations for elements

17.

How many atoms are in the molecule CuSO4?

a)

Five atoms total

b)

Seven atoms total

c)

Four atoms total

d)

Six atoms total

18.

How many different elements are in CuSO4?

a)

Four different elements

b)

Three different elements

c)

Two different elements

d)

Five different elements

19.

What causes a covalent bond between atoms?

a)

Breaking into new elements

b)

Sharing of electrons

c)

Loss of all protons

d)

Absorbing extra neutrons

20.

Which action shows responding to stimuli?

a)

A plant grows toward light

b)

A rock changes its shape

c)

Water boils without heat

d)

Salt turns into sugar

21.

What causes an ionic bond to form between atoms?

a)

Transferring electrons between atoms

b)

Sharing pairs of electrons

c)

Breaking all electron shells

d)

Adding extra neutrons to atoms

22.

When an atom gains electrons, what charge does it have?

a)

Positive overall charge

b)

Negative overall charge

c)

Neutral overall charge

d)

Double positive charge

23.

Which set lists basic properties of water?

a)

Only adhesion without cohesion

b)

Dry and dissolves oils easily

c)

Nonpolar and repels ions

d)

Polar with cohesion and adhesion

24.

Oil and water do not mix because:

a)

Both are ionic substances

b)

Water is polar and oil is nonpolar

c)

Both are polar substances

d)

Water is nonpolar and oil is polar

25.

On a pH scale, where are acids, bases, and neutral substances located?

a)

Acids middle, bases high, neutral low

b)

All are evenly spaced randomly

c)

Acids low, bases high, neutral middle

d)

Acids high, bases low, neutral middle

26.

Which elements are found in carbohydrates?

a)

Carbon, hydrogen, oxygen

b)

Nitrogen, carbon, sulfur

c)

Oxygen, sodium, chlorine

d)

Hydrogen, helium, neon

27.

What are the building blocks of carbohydrates called?

a)

Polypeptides units

b)

Monosaccharides sugars

c)

Fatty acids chains

d)

Nucleotides bases

28.

Glucose is a monosaccharide while sucrose is a disaccharide. What does this mean?

a)

Glucose has two sugar units

b)

Sucrose has one sugar unit

c)

Both have three sugar units

d)

Glucose has one sugar unit

29.

Which is a function of starch, glycogen, and cellulose?

a)

All three store energy in humans

b)

Cellulose stores energy in animals

c)

Glycogen supports plant cell walls

d)

Starch stores energy in plants

30.

What are the building blocks of fat?

a)

Glycerol and fatty acids

b)

Amino acids and peptides

c)

Monosaccharides units

d)

Nucleotides and bases

31.

How many different amino acids build proteins?

a)

25 amino acids

b)

20 amino acids

c)

15 amino acids

d)

10 amino acids

32.

What is the main energy source for humans according to this unit?

a)

Proteins from meats

b)

Carbohydrates sugars

c)

Water and minerals

d)

Fats and oils

33.

Which statement best describes an enzyme?

a)

A fat that protects organs

b)

A protein that slows reactions

c)

A protein that speeds body reactions

d)

A carbohydrate that stores energy

34.

What helps an enzyme recognize the right molecule to act on?

a)

Its overall electric field

b)

Its substrates and active site

c)

Its fatty acid tails

d)

Its extra neutrons

35.

Which conditions can affect how an enzyme works?

a)

Altitude and gravity

b)

Color and texture

c)

Temperature and pH concentration

d)

Wind and sunlight

36.

What does magnification allow a microscope to do?

a)

Make objects appear larger

b)

Make colors change quickly

c)

Make living cells glow

d)

Make samples freeze solid

37.

What does resolution allow a microscope to do?

a)

Measure object mass precisely

b)

Detect heat from samples

c)

Create 3D moving images

d)

Distinguish small close objects

38.

Which lenses on a microscope are right above the slide on the stage?

a)

Coarse focus knobs on the arm

b)

Objective lenses near the stage

c)

Eyepiece lenses at the top

d)

Condenser lenses under the stage

39.

Which set lists the three common objective powers on a light microscope?

a)

Low, medium, high power

b)

Small, larger, largest zoom

c)

Short, middle, longest lens

d)

Starter, regular, expert mode

40.

How do you find total magnification on a microscope?

a)

Subtract objective from eyepiece

b)

Divide eyepiece by objective

c)

Add eyepiece and objective

d)

Multiply eyepiece by objective

41.

What does field of view mean when looking through a microscope?

a)

The white circle you can see

b)

The black edges around glass

c)

The metal frame of the scope

d)

The pointer line inside lens

42.

Which objective has the largest field of view on a microscope?

a)

Scanning objective lens

b)

High power objective

c)

Oil immersion lens

d)

Medium power objective

43.

Which statement describes the cell theory?

a)

All living things are made of cells

b)

Only animals are built from cells

c)

Cells are only for tiny organisms

d)

Cells appear from nonliving matter

44.

Order these from simplest to most complex: organs, atoms, tissues, molecules, organ systems, cells.

a)

Atoms, molecules, organelles, cells, tissues, organs, organ systems

b)

Molecules, atoms, cells, organelles, organs, tissues, organ systems

c)

Cells, tissues, atoms, molecules, organs, organ systems

d)

Organ systems, organs, tissues, cells, molecules, atoms

45.

Which structure provides support for plant cells and is not in animals?

a)

Endoplasmic reticulum

b)

Central vacuole sack

c)

Flexible cell membrane

d)

Cell wall around the cell

46.

Which organelle produces ATP energy for the cell?

a)

Nucleus in center

b)

Golgi body stacks

c)

Ribosomes on RNA

d)

Mitochondria in cytoplasm

47.

Where does photosynthesis happen inside plant cells?

a)

Lysosomes breaking waste

b)

Ribosomes building proteins

c)

Mitochondria making ATP

d)

Chloroplasts with green pigment

48.

Which is a key difference between prokaryotic and eukaryotic cells?

a)

Both have a nucleus shell

b)

Prokaryotes have many nuclei

c)

Neither cell type has DNA

d)

Eukaryotes have a nucleus

49.

On which organelle are proteins synthesized?

a)

Golgi shipping packages

b)

Nucleus storing DNA codes

c)

Mitochondria power house

d)

Ribosomes making chains

50.

Which organelles are found in plant cells but not animal cells?

a)

Cell wall and chloroplasts

b)

Ribosomes and cytoplasm

c)

Nucleus and mitochondria

d)

Golgi and lysosomes

51.

Which polysaccharide makes up most of the plant cell wall?

a)

Glycogen energy store

b)

Cellulose fiber chains

c)

Starch sugar coils

d)

Chitin insect shells

52.

Which polysaccharide stores glucose in plant cells?

a)

Sucrose in vacuoles

b)

Cellulose in walls

c)

Starch in plastids

d)

Glycogen in animals

53.

What is the main component of the cell membrane?

a)

Phospholipids in layers

b)

Cellulose tough fibers

c)

Proteins only strands

d)

Cholesterol wax rings

54.

Which best states the function of the nucleus?

a)

Breaks down old organelles

b)

Packages molecules for use

c)

Controls activities, stores DNA

d)

Makes proteins for export

55.

What thread-like organelles help filter debris from entering the lungs?

a)

Cilia moving mucus

b)

Villi absorbing food

c)

Flagella pushing cells

d)

Microtubules giving shape

56.

Which cell part controls movement of materials into and out of the cell?

a)

Nucleus control center

b)

Rough ER network

c)

Cell membrane barrier

d)

Mitochondria powerhouse

57.

What is homeostasis?

a)

Keeping internal conditions stable

b)

Breaking down food for energy

c)

Moving water out of the cell

d)

Storing genetic instructions

58.

What happens at the rough endoplasmic reticulum?

a)

Protein synthesis with ribosomes

b)

Lipid storage and release

c)

DNA replication for division

d)

Waste breakdown by enzymes

59.

As a cell gets larger, what changes make transport harder?

a)

Volume grows faster than surface area

b)

Surface area grows faster than volume

c)

Surface area and volume stay equal

d)

Both surface area and volume shrink

60.

What is active transport?

a)

Water flow across a membrane

b)

Diffusion using transport proteins

c)

Movement down concentration without energy

d)

Movement against concentration using energy

61.

Which process brings materials into the cell?

a)

Endocytosis inward movement

b)

Exocytosis outward movement

c)

Osmosis water balance

d)

Mitosis cell division

62.

The double layer of phospholipids in membranes is called the:

a)

Phospholipid bilayer structure

b)

Protein filament meshwork

c)

Carbohydrate capsule coat

d)

Nucleic acid lattice

63.

Which proteins send signals from outside the cell to inside?

a)

Ribosomal proteins builders

b)

Carrier proteins transporters

c)

Marker proteins nametags

d)

Receptor proteins messengers

64.

In a saltwater solution, what is the solute?

a)

Salt that gets dissolved

b)

Water that does dissolving

c)

Air bubbles floating

d)

Sugar crystals forming

65.

What does a marker protein help do?

a)

Pump water out of cell

b)

Attach ribosomes to ER

c)

Break sugars into energy

d)

Identify the cell for immunity

66.

Which statement describes diffusion?

a)

Water moves through a membrane only

b)

Proteins build new membranes

c)

Molecules move high to low concentration

d)

Ions move against gradient using ATP

67.

Osmosis is best described as:

a)

Movement of solids across a membrane

b)

Bulk movement by vesicles

c)

Diffusion of water across a membrane

d)

Active pumping of sodium ions

68.

Facilitated diffusion uses what to help particles cross?

a)

Transport proteins in membranes

b)

Energy from ATP molecules

c)

Large vesicles and vacuoles

d)

Sugar chains on lipids

69.

Why are diffusion, osmosis, and facilitated diffusion called passive?

a)

They do not require energy (ATP)

b)

They need constant cell energy

c)

They only move against gradients

d)

They stop at the cell membrane

70.

Which factors can affect diffusion speed?

a)

Color, shape, smell, taste

b)

Sunlight, wind, sound, gravity

c)

Length, width, height, weight

d)

Gradient, temperature, size, permeability

71.

What do channel proteins form to let polar substances pass?

a)

Doughnut-shaped openings

b)

Long fibers and ropes

c)

Flat sheets and layers

d)

Sticky traps and nets

72.

Cells use ATP to pump sodium ions out; which proteins then carry sodium back in with other substances?

a)

Carrier proteins co-transport

b)

Receptor proteins signal

c)

Structural proteins support

d)

Marker proteins label

73.

A cell with 90% water inside is placed in pure water. What type of solution is outside the cell?

a)

Supertonic to the cell

b)

Isotonic with the cell

c)

Hypotonic to the cell

d)

Hypertonic to the cell

74.

When the outside and inside of a cell both have 90% water and 10% starch, the solution is called what?

a)

Plasmolyzed cell state

b)

Isotonic with the cell

c)

Hypotonic to the cell

d)

Hypertonic to the cell

75.

A cell in 80% water outside and 90% water inside is in which type of solution?

a)

Aquatonic to the cell

b)

Isotonic with the cell

c)

Hypertonic to the cell

d)

Hypotonic to the cell

76.

Which process moves molecules across the membrane without using cellular energy?

a)

Exocytosis with energy use

b)

Endocytosis requiring ATP

c)

Passive transport without ATP

d)

Active transport using ATP

77.

Which statement best describes water movement for a cell in a hypertonic solution?

a)

Water enters until the cell swells

b)

Water moves equally both directions

c)

Water leaves and the cell shrinks

d)

Water movement stops completely

78.

Which equation correctly shows photosynthesis?

a)

C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP

b)

6CO2 + 6H2O + light → C6H12O6 + 6O2

c)

6CO2 + 6O2 + light → H2O + glucose

d)

C6H12O6 → 6CO2 + 6O2 + light

79.

Which equation represents cellular respiration?

a)

6CO2 + ATP → C6H12O6 + 6O2

b)

C6H12O6 + light → 6CO2 + 6O2 + ATP

c)

C6H12O6 + 6O2 → 6CO2 + 6H2O + ATP

d)

6CO2 + 6H2O + light → C6H12O6 + 6O2

80.

What are the reactants needed for photosynthesis?

a)

Water and carbon dioxide

b)

Oxygen and ATP

c)

Glucose and oxygen

d)

Water and glucose

81.

What is the ultimate source of energy for life on Earth?

a)

Earth’s core

b)

ATP

c)

Glucose

d)

The sun

82.

What is a photon?

a)

A packet of light energy

b)

A packet of heat energy

c)

A packet of sound energy

d)

A packet of chemical energy

83.

The color we see is the light reflected, while other accessory pigments do what with all other light?

a)

reflect more wavelengths of light

b)

absorb all other light wavelengths

c)

scatter light in the air

d)

transmit light through leaves

84.

Which statement best explains the difference between producers and consumers?

a)

Consumers make food using sunlight

b)

Consumers store sunlight inside leaves

c)

Producers eat other organisms for energy

d)

Producers make their own food using sunlight

85.

Which definition matches heterotrophs?

a)

Organisms that breathe oxygen at night

b)

Organisms that only absorb sunlight

c)

Organisms that make their own food

d)

Organisms that must consume food for energy

86.

Which definition matches autotrophs?

a)

Organisms that consume food for energy

b)

Organisms that live without sunlight

c)

Organisms that make their own food

d)

Organisms that hibernate in winter

87.

What happens to chlorophyll in leaves during the fall?

a)

Chlorophyll absorbs less oxygen

b)

Chlorophyll turns into sugars

c)

Chlorophyll breaks down in leaves

d)

Chlorophyll becomes brighter green

88.

What color is chlorophyll?

a)

yellow

b)

green

c)

red

d)

blue

89.

Chromatography is best described as which technique?

a)

Freezing pigments to preserve them

b)

Heating pigments to change color

c)

Separating pigments by how fast they move

d)

Mixing pigments to create new colors

90.

Identify the inputs to the light reaction.

a)

Water, carbon dioxide, glucose

b)

Light, oxygen, ATP, NADPH

c)

Light, carbon dioxide, chlorophyll

d)

Light, water, ADP, NADP+

91.

Identify the outputs of the light reaction.

a)

Oxygen, ATP, NADPH

b)

Glucose, ATP, NADP+

c)

Carbon dioxide, glucose, water

d)

Oxygen, ADP, NADP+

92.

Light is absorbed by which molecule embedded in the thylakoid membrane?

a)

Glucose

b)

ATP

c)

Chlorophyll

d)

NADPH

93.

Where does the light reaction occur inside the chloroplast?

a)

Mitochondria inner space

b)

Thylakoid membrane chloroplast

c)

Cytoplasm of the cell

d)

Stroma region of chloroplast

94.

What is another name for the Calvin Cycle?

a)

Light independent reactions

b)

Light dependent reactions

c)

Electron transport reactions

d)

Photosynthetic light cycle

95.

What is the main output of the Calvin Cycle, and what is it used for?

a)

ATP used for muscle movement

b)

Glucose used for energy and building

c)

NADPH used for absorbing light

d)

Oxygen used for breathing

96.

When and where can the dark reaction occur?

a)

Only at night in thylakoids

b)

Anytime in stroma of chloroplasts

c)

Anytime in mitochondria matrix

d)

Only in daytime in stroma

97.

During photosynthesis, where does oxygen come from?

a)

Breaking down carbon dioxide gas

b)

Splitting of water in light reactions

c)

Calvin Cycle releases oxygen

d)

Using oxygen stored in leaves

98.

Which parts of the cell are involved in cellular respiration?

a)

Ribosomes and Golgi body

b)

Vacuoles and lysosomes

c)

Nucleus and chloroplasts

d)

Cytoplasm and mitochondria

99.

NAD+ and FAD+ are best known as what?

a)

Sugar transporters

b)

Oxygen producers

c)

Electron acceptors

d)

Light energy carriers

100.

Which statement describes fermentation?

a)

Aerobic process making ATP with oxygen

b)

Anaerobic process making ATP without oxygen

c)

Reaction that breaks down chlorophyll

d)

Process storing sunlight in chlorophyll

101.

How does fermentation differ in animals versus plants?

a)

Animals use alcoholic fermentation

b)

Plants use lactic acid fermentation

c)

Animals use oxygen to make ATP

d)

Animals use lactic acid fermentation

102.

Which type of fermentation causes muscle soreness?

a)

Lactic acid fermentation

b)

Alcoholic fermentation

c)

Calvin Cycle fermentation

d)

Water-splitting fermentation

103.

Which list shows the correct order of aerobic respiration steps?

a)

Glycolysis, electron transport, Krebs cycle

b)

Krebs cycle, electron transport, glycolysis

c)

Electron transport, glycolysis, Krebs cycle

d)

Glycolysis, Krebs cycle, electron transport

104.

About how many ATP are made from one glucose in aerobic respiration?

a)

36–38 ATP total

b)

8–10 ATP total

c)

100–120 ATP total

d)

2–4 ATP total

105.

Where is energy stored in an ATP molecule?

a)

In bonds between phosphate groups

b)

Inside the sugar ribose ring

c)

In the adenine nitrogen base

d)

Around the cell membrane proteins

106.

What is the best definition of mitosis?

a)

Division of a nucleus making two identical cells

b)

Copying DNA without splitting the cell

c)

Joining two cells to form one larger cell

d)

Division that makes four different cells

107.

Put the mitosis stages in the correct order.

a)

Telophase, Anaphase, Metaphase, Prophase

b)

Metaphase, Prophase, Telophase, Anaphase

c)

Prophase, Metaphase, Anaphase, Telophase

d)

Anaphase, Telophase, Prophase, Metaphase

108.

What happens during anaphase of mitosis?

a)

Sister chromatids separate and move apart

b)

Chromosomes line up across the center

c)

Nuclear membrane breaks down

d)

Two new nuclei finish forming

109.

Which sequence correctly names the cell cycle?

a)

Interphase, Mitosis, Cytokinesis

b)

Cytokinesis, Interphase, Mitosis

c)

Mitosis, Cytokinesis, Interphase

d)

Interphase, Cytokinesis, Mitosis

110.

During which stage does a cell spend most of its time?

a)

Metaphase stage mostly

b)

Interphase stage mostly

c)

Mitosis stage mostly

d)

Cytokinesis stage mostly

111.

Which statement describes a chromatid and a centromere?

a)

Chromatid is DNA base; centromere is outer cell wall

b)

Chromatid is cell fluid; centromere is the nucleus center

c)

Chromatid is a full chromosome; centromere makes spindle fibers

d)

Chromatid is half a duplicated chromosome; centromere joins sisters

112.

Which choice explains haploid versus diploid?

a)

Haploid one set of chromosomes; diploid two sets

b)

Haploid two sets of chromosomes; diploid one set

c)

Haploid only X chromosomes; diploid only Y

d)

Haploid no chromosomes; diploid many sets

113.

Homologous chromosomes are best described as what?

a)

Identical copies, carry no genes, from neither parent

b)

Same size and shape, carry same genes, one from each parent

c)

Random pieces, carry extra genes, from a grandparent

d)

Different sizes, carry unrelated genes, both from one parent

114.

How many chromosomes are in human haploid and diploid cells?

a)

Haploid 23; Diploid 23

b)

Haploid 12; Diploid 24

c)

Haploid 23; Diploid 46

d)

Haploid 46; Diploid 92

115.

How does a bacterial cell divide?

a)

By budding making three small cells

b)

By mitosis making four different cells

c)

By meiosis making many varied cells

d)

By binary fission making two identical cells

116.

Why is Meiosis I called reduction division?

a)

DNA amount stays exactly the same

b)

Only cytoplasm is reduced, not chromosomes

c)

Chromosome number reduces from diploid to haploid

d)

Chromosome number increases to double haploid

117.

What is nondisjunction and one result in humans?

a)

Chromosomes melt away; can cause hair loss

b)

Chromosomes copy twice; can cause taller height

c)

Chromosomes fail to separate; can cause Down syndrome

d)

Chromosomes skip prophase; can cause colds

118.

During prophase in mitosis, which events occur first?

a)

Chromosomes uncoil; nuclear pores open; cell rests

b)

Chromosomes line up; centrioles disappear; cytokinesis begins

c)

Chromosomes split; nuclei reform; spindles vanish

d)

Chromosomes condense; nuclear membrane breaks; spindles form

119.

During metaphase of mitosis, what key event happens?

a)

Cell grows and copies its DNA

b)

Nuclear membranes reform fully

c)

Chromosomes line up at the cell center

d)

Sister chromatids move to opposite poles

120.

During telophase of mitosis, what completes forming?

a)

Nuclear membranes reform around chromosomes

b)

Spindle fibers begin to form quickly

c)

Chromosomes condense into thick rods

d)

DNA is copied for the first time

121.

Which part of aerobic respiration produces most ATP?

a)

Krebs cycle matrix step

b)

Glycolysis cytoplasm step

c)

Fermentation backup step

d)

Electron transport chain step

122.

Which cell type is haploid in humans?

a)

Skin cells on your arm

b)

Gametes like eggs and sperm

c)

Brain nerve cells

d)

Muscle cells in your leg

123.

Which process can create genetic variation during cell reproduction?

a)

Chromosome crossing over

b)

Cells skipping mitosis

c)

Chromosome copying only

d)

Nucleus staying the same

124.

Which stage of mitosis shows chromosomes lined up in the middle of the cell?

a)

Metaphase stage

b)

Prophase stage

c)

Telophase stage

d)

Interphase stage

125.

What is the main purpose of a Punnett square?

a)

Predict possible offspring traits

b)

Measure cell sizes in tissues

c)

Count chromosomes in a cell

d)

Draw family trees for ancestors

126.

Genotype is best described as

a)

A blood type group

b)

A person’s visible trait

c)

A cell’s energy source

d)

An organism’s allele combination

127.

If T is dominant and t is recessive, which genotype is heterozygous?

a)

Tt genotype

b)

TT genotype

c)

tt genotype

d)

ttT genotype

128.

Why are males more likely to show X‑linked traits?

a)

They have one X chromosome

b)

They have two X chromosomes

c)

They have larger cells

d)

They have more DNA bases

129.

Which three events can lead to genetic variation?

a)

Dominance, recessiveness, codominance

b)

METAPHASE, ANAPHASE, TELOPHASE

c)

Photosynthesis, respiration, digestion

d)

Mutation, crossing over, independent assortment

130.

In a simple dominance cross, which allele masks the other?

a)

Dominant allele

b)

Silent allele

c)

Codominant allele

d)

Recessive allele

131.

What molecule is the genetic material for all living things?

a)

Amino acid chains

b)

Deoxyribonucleic acid

c)

Starch sugar units

d)

Mineral salt crystals

132.

Griffith’s experiments helped show that

a)

Traits skip meiosis

b)

Proteins create sunlight

c)

DNA can transform bacteria

d)

Cells breathe underwater

133.

Avery and Hershey‑Chase provided evidence that

a)

Protein, not DNA, is genetic

b)

RNA, not DNA, makes bones

c)

Sugar, not DNA, stores energy

d)

DNA, not protein, carries heredity

134.

Watson and Crick discovered the DNA

a)

Double helix structure

b)

Square lattice shape

c)

Triple spiral shape

d)

Single loop shape

135.

Which pairing correctly matches genotype and phenotype?

a)

Genotype: allele combo; phenotype: observable traits

b)

Genotype: blood type test; phenotype: gene location

c)

Genotype: family tree; phenotype: cell division stage

d)

Genotype: visible height; phenotype: DNA letter order

136.

What did Chargaff contribute to our understanding of DNA?

a)

Sugars bond to phosphate only

b)

A=T and G=C pairing rule

c)

RNA pairs A=U in cells

d)

DNA is made of proteins

137.

What are the three parts of a nucleotide?

a)

Deoxyribose sugar, phosphate group, nitrogenous base

b)

Ribose sugar, lipid tail, amino group

c)

Protein chain, fatty acid, water

d)

Phosphate only, sugar only, base only

138.

Identify the basic building block of DNA and its components.

a)

Nucleotide: deoxyribose sugar, phosphate group, nitrogenous base

b)

Chromosome: protein, water, salt

c)

Amino acid: ribose sugar, lipid, nitrogen gas

d)

Cell: cytoplasm, membrane, chlorophyll

139.

The backbone of DNA is composed of what two molecules?

a)

Proteins and lipids alternating

b)

Nitrogen bases and amino acids alternating

c)

Water molecules and salts alternating

d)

Phosphate group and deoxyribose sugars alternating

140.

Describe the molecule of DNA using the terms pyrimidine and purine.

a)

Flat ladder with ionic bonds; purines U or C; pyrimidines A or G

b)

Single helix with covalent bonds; purines T or C; pyrimidines A or G

c)

Triple helix without bonds; purines are bases only; pyrimidines are sugars

d)

Double helix with hydrogen bonds; purines A or G; pyrimidines T or C

141.

Name the four nitrogen bases in DNA.

a)

Adenine, Uracil, Guanine, Cytosine

b)

Uracil, Thymine, Guanine, Adenine

c)

Cytosine, Ribose, Adenine, Thymine

d)

Adenine, Thymine, Guanine, Cytosine

142.

What is the complementary strand of G G C A T T A G C T A G C T A?

a)

CCGTAATCGATCGAT

b)

CCGTAAUCGATUGA

c)

GGCAATTCGATCGA

d)

TTGCAAUAGCUAGU

143.

Explain the process of DNA replication, making sure to include the enzymes.

a)

Polymerase melts sugars; ligase breaks bonds; helicase repairs

b)

Sugars unzip; bases float; proteins randomly attach

c)

Ligase unwinds; helicase glues; polymerase stops copying

d)

Helicase unwinds; DNA polymerase builds and proofreads; ligase glues