wayground logo

Free Printable Worksheets

Font size

S
M
L
XL
Worksheets

AP Bio Semester 1 Final Review

Total questions: 110

Worksheet time: 2hrs 50mins

Name
Class
Date
1.

Which of the following functional groups

characterizes RNA?

a)

A PO3 group, deoxyribose, and uracil

b)

A PO3 group, ribose, and uracil

c)

A PO3 group, ribose, and thymine

d)

A PO2 group, deoxyribose, and uracil

e)

A PO2 group, deoxyribose, and thymine

2.

Which of the following molecules would contain

a polar covalent bond?

a)

Cl2

b)

NaCl

c)

H2O

d)

KBr

e)

C6H12O6

3.

Which of the following compounds would NOT

be water-soluble?

a)

Potassium chloride

b)

Fatty acids

c)

Fructose

d)

Cellulose

e)

Hydrogen Bromide

4.

Three terms associated with the travel of water

from the roots up through the vascular tissues of

plants are

a)

Adhesion, cohesion and translocation

b)

Adhesion, cohesion, and transcription

c)

Cohesion, hybridization, and

transpiration

d)

Cohesion, adhesion, and transpiration

e)

Transpiration, neutralization, and

adhesion

5.

Match the appropriate term or concept

with the phrase that best describes it.

Contain one or more double bonds

a)

lipids

b)

peptide bonds

c)

alpha helix

d)

unsaturated fatty acid

e)

cellulose

6.

Match the appropriate term or concept

with the phrase that best describes it.

one of the four major classes of biological

molecules that are not polymers

a)

lipids

b)

peptide bonds

c)

alpha helix

d)

unsaturated fatty acid

e)

cellulose

7.

Match the appropriate term or concept

with the phrase that best describes it.

linkages between the monomers of proteins

a)

lipids

b)

peptide bonds

c)

alpha helix

d)

unsaturated fatty acid

e)

cellulose

8.

Match the appropriate term or concept

with the phrase that best describes it.

a secondary structure of proteins

a)

lipids

b)

peptide bonds

c)

alpha helix

d)

unsaturated fatty acid

e)

cellulose

9.

Match the appropriate term or concept

with the phrase that best describes it.

the storage form of carbohydrates in plants

a)

lipids

b)

peptide bonds

c)

alpha helix

d)

unsaturated fatty acid

e)

cellulose

10.

The process by which protein conformation is

lost or broken down is

a)

Decondensation

b)

Deconstruction

c)

Denaturation

d)

Hydrolysis

e)

Hybridization

11.

Which of the following theories or laws states

that every energy transfer increases the amount

of entropy in the universe?

a)

The free energy law

b)

The first law of thermodynamics

c)

The second law of thermodynamics

d)

Evolutionary theory

e)

Chaos Theory

12.

Catalysts speed up chemical reactions by

a)

Decreasing the free energy change of the reaction

b)

Increasing the free energy change of the reaction

c)

Degrading the competitive inhibitors in a reaction

d)

Lowering the activation energy of the reaction

e)

Raising the activation energy of the reaction

13.

Match the appropriate term or concept with the phrase that best describes it.

Describes inhibition by an enzyme that is capable of either activating or inhibiting a metabolic pathway

a)

Allosteric inhibition

b)

Feedback inhibition

c)

Competitive inhibitor

d)

Noncompetitive inhibitor

e)

Cooperativitity

14.

Match the appropriate term or concept with the phrase that best describes it.

A reversible inhibitor that looks similar to the normal substrate and competes for the active site of the enzyme

a)

Allosteric inhibition

b)

Feedback inhibition

c)

Competitive inhibitor

d)

Noncompetitive inhibitor

e)

Cooperativitity

15.

Match the appropriate term or concept with the phrase that best describes it.

The process by which the binding of the substrate to the enzyme triggers a favorable conformation change, which causes a similar change in all of the proteins’ subunits

a)

Allosteric inhibition

b)

Feedback inhibition

c)

Competitive inhibitor

d)

Noncompetitive inhibitor

e)

Cooperativitity

16.

Match the appropriate term or concept with the phrase that best describes it.

The process by which a metabolic pathway is shut off by the product it produces

a)

Allosteric inhibition

b)

Feedback inhibition

c)

Competitive inhibitor

d)

Noncompetitive inhibitor

e)

Cooperativitity

17.

Match the appropriate term or concept with the phrase that best describes it.

Binds to the enzyme at a site other than the active site, causing the enzyme to change shape and be unable to bind to the substrate

a)

Allosteric inhibition

b)

Feedback inhibition

c)

Competitive inhibitor

d)

Noncompetitive inhibitor

e)

Cooperativitity

18.

When a water molecule loses an H+ in solution, and another water molecules accepts the proton, what is the water molecules that accepts the proton called?

a)

A hydroxide ion

b)

Crystal lattice structure

c)

A solution not in equilibrium

d)

A hydronium ion

e)

A basic solution

19.

A student looking through a light microscope would not be able to see any of the following cell structures EXCEPT

a)

ribosomes

b)

a Golgi apparatus

c)

a nucleus

d)

an endoplasmic reticulum

e)

a peroxisome

20.

Prokaryotic and eukaryotic cells have all of the following structures in common EXCEPT

a)

plasma membrane

b)

protein-complexed DNA

c)

nucleoid region

d)

cilia

e)

cytoplasm

21.

Match the appropriate term or concept with the phrase that best describes it.

An organelle that is characterized by extensive, folded membranes, and is often associated with ribosomes.

a)

peroxisome

b)

Golgi apparatus

c)

Lysosomes

d)

Endoplasmic reticulum

e)

Mitochondria

22.

Match the appropriate term or concept with the phrase that best describes it.


An organelle with a cis and trans face, which acts as the packaging and secreting center of the cell.

a)

peroxisome

b)

Golgi apparatus

c)

Lysosomes

d)

Endoplasmic reticulum

e)

Mitochondria

23.

Match the appropriate term or concept with the phrase that best describes it.


The sites of cell respiration.

a)

peroxisome

b)

Golgi apparatus

c)

Lysosomes

d)

Endoplasmic reticulum

e)

Mitochondria

24.

Match the appropriate term or concept with the phrase that best describes it.


Single-membrane structures I the cell that perform many metabolic functions and produce hydrogen peroxide.

a)

peroxisome

b)

Golgi apparatus

c)

Lysosomes

d)

Endoplasmic reticulum

e)

Mitochondria

25.

Match the appropriate term or concept with the phrase that best describes it.


Large membrane-bound structures that contain hydrolytic enzymes and that exist only in animal cells.

a)

peroxisome

b)

Golgi apparatus

c)

Lysosomes

d)

Endoplasmic reticulum

e)

Mitochondria

26.

Which of the following molecules is a typical component of the animal cell membrane?

a)

Starch

b)

Glucose

c)

nucleic acid

d)

carbohydrates

e)

Vitamin K

27.

Which of the following is an example of passive transport across the cell membrane?

a)

The travel of an action potential down a muscle cell.

b)

The uptake of nutrients by the microvilli of cells lining the stomach.

c)

The movement of insulin across the cell membrane.

d)

The movement of carbon dioxide across the cell membrane.

e)

The selective uptake of hormones across the cell membrane.

28.

Large molecules are moved out of the cell by which of the following processes?

a)

pinocytosis

b)

phagocytosis

c)

receptor-mediated endocytosis

d)

cytokinesis

e)

exocytosis

29.

The purpose of cell respiration in a eukaryotic cell is to

a)

synthesize carbohydrates from CO2

b)

synthesize fats and proteins from CO2

c)

break down carbohydrates to provide energy to provide energy for the cell in the form of ATP

d)

break down carbohydrates to provide energy for the cell in the form of ADP

e)

provide oxygen to the cell.

30.

The net result of glycolysis is

a)

4 ATP and 4 NADH

b)

4 ATP and 2 NADH

c)

2 ATP and 4 NADH

d)

2 ATP and 2 NADH

e)

4 ATP and 8 NADH

31.

In the course of the Krebs cycle, how many molecules

of ATP are produced?

a)

1

b)

2

c)

3

d)

4

e)

5

32.

The process that produces the largest amount of ATP during respiration is

a)

glycolysis

b)

fermentation

c)

the Krebs cycle

d)

the electron transport chain

e)

chemiosmosis and oxidative phosphorylation

33.

The process by which a hydrogen gradient is used to create ATP

a)

Chemiosmosis

b)

Electron transport chain

c)

The Krebs cycle

d)

Glycolysis

e)

Fermentation

34.

The process that makes a small amount of ATP and can produce lactic acid as a by product

a)

Chemiosmosis

b)

Electron transport chain

c)

The Krebs cycle

d)

Glycolysis

e)

Fermentation

35.

A series of membrane embedded electron carriers that ultimately create the hydrogen ion gradient to drive the synthesis of ATP

a)

Chemiosmosis

b)

Electron transport chain

c)

The Krebs cycle

d)

Glycolysis

e)

Fermentation

36.

The process by which the breakdown of glucose is completed and CO2 is produced

a)

Chemiosmosis

b)

Electron transport chain

c)

The Krebs cycle

d)

Glycolysis

e)

Fermentation

37.

Muscle fatigue is caused when the process of fermentation in oxygen-depleted cells produces which of the following?

a)

ADP

b)

Ethanol

c)

Lactate

d)

Uric acid

e)

Pyruvate

38.

Groups of photosynthetic pigment molecules situated in the thylakoid membrane are called:

a)

photosystems

b)

carotenoids

c)

chlorophyll

d)

granna

e)

CAM plants

39.

The reactions of the Calvin cycle are also known as the dark reactions because these reactions

a)

occur in plants only at night

b)

occur in dark-staining cells of plant leaves

c)

must absorb black light from the spectrum in order to proceed

d)

do not require light in order to proceed

e)

take place only during the day

40.

The major product of the Calvin cycle is

a)

rubisco

b)

oxaloacetate

c)

ribulose bisphophate

d)

pryruvate

e)

glyceraldehydes-3-phaosphate

41.

All of the following statements about photosynthesis are true EXCEPT

a)

the light reactions convert solar energy to chemical energy in the form of ATP and NADPH

b)

the Calvin cycle uses ATP and NADPH to convert CO2 to sugar

c)

photosystem I contains P700 chlorophyll a molecules at the reaction center; photosystem II contains P680 molecules.

d)

in chemiosmosis, electron transport chains pump protons (H+) across a membrane from a region of high H+ concentration to a region of low H+ concentration

e)

the steps of the Calvin cycle are sometimes referred to as the dark reactions, because they do not require light in order to take place

42.

The accumulation of free oxygen in Earth's atmosphere began _____

a)

with the origin of life and respiratory metabolism

b)

with the origin of cyanobacteria that had both photosystem I and photosystem II

c)

with the origin of photosynthetic bacteria that had photosystem I

d)

with the origin of land plants

43.

A molecule that has been phosphorylated

a)

has a decreased chemical reactivity; it is less likely to provide energy for cellular work

b)

has an increased chemical potential energy; it is primed to do cellular work.

c)

has been oxidized as a result of a redox reaction involving the gain of an inorganic phosphate.

d)

has less energy than before its phosphorylation and therefore less energy for cellular work.

44.

A student does an experiment to measure the rate of photosynthesis of spinach leaf disks. She decides to compare different colors of water to see if they affect the rate. Which color would you expect to have the highest rate of photosynthesis based on your knowledge of light and photosynthesis?

a)

Green

b)

Red

c)

Blue

d)

Clear

45.

The graph shows the absorption spectrum for chlorophyll a and the action spectrum for photosynthesis. Based on the information in the graph, which wavelengths lead to the least absorbance?

a)

400-500

b)

600-700

c)

500-600

d)

700-750

46.

Which wavelength of light in the figure is most effective for absorbance of chlorophyll a?

a)

400 nm

b)

450 nm

c)

600 nm

d)

675 nm

47.

During photosynthesis, electrons travel downhill in which sequence?

a)

food → NADH → electron transport chain → oxygen

b)

water → photosystem II → electron transport chain → NADPH

c)

glucose → pyruvate → ATP → oxygen

d)

light → electron transport chain → chlorophyll --> ATP

48.

Where are the proteins of the electron transport chain used in photosynthesis located?

a)

thylakoid membrane

b)

granna

c)

chloroplast outer membrane

d)

stroma

49.

To test the hypothesis that a particular plant synthesizes storage lipids by using G3P from photosynthesis, a researcher plans to use radiolabeled precursors to track the molecules through the biosynthetic pathway. Which of the following radiolabeled precursors is most appropriate for the research to use?

a)

15Nitrogen-labeled N2, because atmosphere nitrogen is fixed to amino acids by photosynthesis.

b)

35Sulfur-labeled methionine, because amino acids are incorporated into lipids during photosynthesis.

c)

14Carbon-labeled CO2, because atmosphere carbon is fixed to carbohydrates by photosynthesis.

d)

32Phosphorous-labeled phosphate, because lipids are stored in plants as phospholipids.

50.

The function of the plasma membrane is....

a)

to regulate what enters and leaves the cell.

b)

provide rigid support and protection to the cell.

c)

fight bacteria and viruses that enter the cell.

d)

make sure each cell can move

51.

A phospholipid has 2 parts. What are they called?

a)

Hydrophilic Head, Hydrophobic Tail

b)

Hydrophobic Head, Hydrophilic Tail

c)

Hydrophallic Head, Hydrophilic Tail

d)

Hydrophilic Head, Hydrophallic Tail

52.

Hydrophobic region of the cell membrane?

a)

A

b)

B

c)

C

d)

D

e)

E

53.

Hydrophilic region of the cell membrane?

a)

A

b)

B

c)

C

d)

D

e)

E

54.

What do the brown structures represent?

a)

Phospholipids

b)

Channel Proteins

c)

Glycoproteins

d)

Cyctoskeleton Filaments

55.

What molecule plays and important role in controlling cell membrane fluidity?

a)

Insulin

b)

Triglyceride

c)

Testosterone

d)

Cholesterol

56.

Which term BEST matches the definition below:

Nuclear membrane begins to reform, DNA unwinds from histones

a)

Telophase

b)

Interphase

c)

Cytokinesis

d)

Prometaphase

e)

Anaphase

57.

Which term BEST matches the definition below:


Division of the cytoplasm of the cell.

a)

Telophase

b)

Interphase

c)

Cytokinesis

d)

Prometaphase

e)

Anaphase

58.

Which term BEST matches the definition below:


Sister chromatids begin to separate

a)

Telophase

b)

Interphase

c)

Cytokinesis

d)

Prometaphase

e)

Anaphase

59.

Which term BEST matches the definition below:


The genetic material of the cell replicates to prepare for cell division

a)

Telophase

b)

Interphase

c)

Cytokinesis

d)

Prometaphase

e)

Anaphase

60.

Which term BEST matches the definition below:


Microtubules begin to attach to the centromeres of the sister chromatids

a)

Telophase

b)

Interphase

c)

Cytokinesis

d)

Prometaphase

e)

Anaphase

61.

The figure at above shows a cell in what stage of mitosis?

a)

prophase

b)

prometaphase

c)

metaphase

d)

anaphase

e)

telophase

62.

After which of the following checkpoints in the cell cycle is the cell fated to divide?

a)

G2 phase checkpoint

b)

M phase checkpoint

c)

Interphase checkpoint

d)

G1 phase checkpoint

e)

MPF checkpoint

63.

A couple has 6 children, all daughters. If the woman has a seventh child, what is the probability that the seventh child will be a daughter?

a)

6/7

b)

1/7

c)

1/36

d)

1/49

e)

1/2

64.

All of the following are true of the process of mitosis EXCEPT

a)

during prometaphse, spindle microtubles come into contact with chromosomes

b)

the chromosome number in the newly formed cells is half that of the parent cell

c)

the chromosomes line up along the metaphase plate, or equator of the cell

d)

the cytoplasm of the cell and all its organelles are divided approximately in half

e)

in anaphase, the sister chromatids travel to opposite ends of the cell

65.

In most organisms, reproduction occurs sexually; two parents are involved and genetic recombination occurs. However, some organisms reproduce asexually, and only one parent contributes genetic material. Which of the following organisms reproduce asexually?

a)

Annelids

b)

Arthropods

c)

Hydra

d)

Angiosperms

e)

Gymnosperms

66.

All of the following nitrogenous bases are included in DNA EXCEPT

a)

Adenine

b)

Guanine

c)

Cytosine

d)

Thymine

e)

Uracil

67.

Which term BEST fits the definition below:

A mobile segment of DNA that travels from one location on a chromosome to another, one element of genetic change.

a)

transcription

b)

translation

c)

transposon

d)

DNA methylation

e)

Histone acetylation

68.

Which term BEST fits the definition below:


The addition of methyl groups to certain bases of DNA after DNA synthesis, this is thought to be an important control mechanism for gene expression.

a)

transcription

b)

translation

c)

transposon

d)

DNA methylation

e)

Histone acetylation

69.

Which term BEST fits the definition below:


The synthesis of polypeptides from the genetic information coded in mRNA.

a)

transcription

b)

translation

c)

transposon

d)

DNA methylation

e)

Histone acetylation

70.

Which term BEST fits the definition below:


The synthesis of RNA from a DNA template

a)

transcription

b)

translation

c)

transposon

d)

DNA methylation

e)

Histone acetylation

71.

Which term BEST fits the definition below:


The attachment of acetyl groups to particular amino acids of histone proteins, this is thought to be an important control mechanism for gene expression.

a)

transcription

b)

translation

c)

transposon

d)

DNA methylation

e)

Histone acetylation

72.

Which term BEST fits the definition below:

An example of a post-transcriptional modification

a)

tRNA

b)

mRNA

c)

poly-A-tail

d)

RNA Polymerase

e)

rRNA

73.

Which term BEST fits the definition below:


Binds to the promoter on DNA to initiate transcription

a)

tRNA

b)

mRNA

c)

poly-A-tail

d)

RNA Polymerase

e)

rRNA

74.

Which term BEST fits the definition below:


Along with proteins, comprise ribosomes

a)

tRNA

b)

mRNA

c)

poly-A-tail

d)

RNA Polymerase

e)

rRNA

75.

Which term BEST fits the definition below:


Loosely binds to free amino acids in the cytoplasm

a)

tRNA

b)

mRNA

c)

poly-A-tail

d)

RNA Polymerase

e)

rRNA

76.

Which term BEST fits the definition below:


Travels out of the nucleus and into the cytoplasm to participate in translation

a)

tRNA

b)

mRNA

c)

poly-A-tail

d)

RNA Polymerase

e)

rRNA

77.

The actions of which of the following enzymes are responsible for ensuring that chromosomes do not decrease in length with every round of replication?

a)

Telomerase

b)

DNA ligase

c)

DNA polymerase

d)

Helicase

e)

Primase

78.

At the end of DNA replication, each of the daughter molecules has one old strand, derived from the parent strand of DNA, and one strand that is newly synthesized. This explains why DNA replication is described as

a)

conservative

b)

largely conservative

c)

nonconservative

d)

semiconservative

e)

unconservative

79.

During photosynthesis

a)

light reactions produce sugar, while the Calvin cycle produces O2

b)

light reactions produce NADPH and ATP, while the Calvin cycle produces sugar.

c)

light reactions photophosphorylate ADP, while the Calvin cycle produces ATP.

d)

the Calvin cycle produces both sugar and O2.

80.

To learn about airborne bacteria, students leave four open Petri dishes filled with agar sitting on a table. At the end of the day, the dishes are covered and then incubated at 38ºC for several days. The most important reason to wear latex gloves when handling the Petri dishes is to keep from –

a)

spreading bacteria to other Petri dishes in the lab area

b)

being poisoned by the agar in the Petri dishes

c)

contaminating the Petri dishes with skin-borne bacteria

d)

exposing the nutrient agar to oils that could denature the agar

81.

The image below shows a polymer of glucose molecules. What type of macromolecule is this?

a)

Carbohydrate

b)

Lipid

c)

Protein

d)

Nucleic Acid

82.

Which material should be disposed of after a lab, rather than being reused or recycled?

a)

broken test tube that had held salt water

b)

cotton swab used to collect cheek cells

c)

scalpel used to dissect plant specimens

d)

large, open bottle of rubbing alcohol

83.

Science has limitations, because -

a)

it can only explain things that are scientifically testable.

b)

some experiments can’t be repeated and therefore should be disregarded.

c)

it can only make decisions regarding moral judgments that some people might struggle with.

d)

decisions about what is actual science information is difficult to determine.

84.

Which statement best describes a testable hypothesis?

a)

It is an assumption which includes a value judgment by the experimenter.

b)

It is an expression of a relationship between observable and measurable variables.

c)

It is a statement that has no basis for comparison.

d)

It is a general explanation based on large amounts of collected data.

85.

Which of the following is a true statement regarding scientific theories such as the Theory of Evolution by Natural Selection?

I.Scientific theories are well established and reliable.

II.Scientific theories have been examined by multiple researchers.

III.Scientific theories are subject to change when new evidence is

inconsistent with or cannot be explained by current theory.

IV.Scientific theories have changed over time.

a)

I & II

b)

II only

c)

II & III

d)

I, II, III, & IV

e)

IV only

86.

Which of these statements is a theory?

a)

The heart pumps deoxygenated blood to the lungs.

b)

All living things are composed of at least one cell, and the cell is the fundamental unit of function in all organisms.

c)

Cell phones, due to the electromagnetic radiation they emit, may cause brain cancer.

d)

Eye color is genetically determined.

87.

The main structural component of the plasma membrane.

a)

cholesterol

b)

phospholipid

c)

protein

d)

nucleic acids

88.

A shortage of phosphorus in the soil would make it difficult to manufacture __.

a)

DNA

b)

proteins

c)

fatty acids

d)

sucrose

89.

What does A represent?

a)

enzyme

b)

allosteric site

c)

active site

d)

substrate

90.

What does C represent?

a)

enzyme

b)

allosteric site

c)

active site

d)

substrate

91.

What is happening at point B?

a)

the enzyme is denatured

b)

the substrate is used up

c)

the enzyme is saturated

d)

the reaction is occurring at its fastest rate

92.

Four elements make up more than 96% of the human body. These include all of the following except __.

a)

Carbon

b)

Nitrogen

c)

Hydrogen

d)

Phosphorus

93.

Cells within this gland secrete a hormone that in times of emergency, increase the glucose level of the blood and speeds up the actions of the circulatory and respiratory systems.

a)

adrenal

b)

thyroid

c)

pancreas

d)

anterior pituitary

94.

Which of the following are products of the light reaction?

a)

ATP and NADH

b)

oxygen and NADPH

c)

glucose and oxygen

d)

carbon dioxide and water

95.

This image is of what type of macromolecule?

a)

lipid

b)

protein

c)

carbohydrate

d)

nucleic acid

96.

Which type of macromolecule is used for long term energy storage?

a)
b)
c)
d)
97.

Which of the following is considered fully saturated?

a)
b)
c)
d)
98.

Which of the following is considered MOSTLY NONPOLAR?

a)
b)
c)
d)
99.

How many amino acids are featured here?

a)

1

b)

2

c)

3

d)

4

e)

5

100.

Meat is considered to contain the highest of which macromolecule?

a)

Protein

b)

Carbohydrate

c)

Lipid

d)

Nucleic Acid

101.

Lugol's reagent tests for the presence of starches. Which type of macromolecule does it test for?

a)

Protein

b)

Carbohydrate

c)

Lipid

d)

Nucleic Acid

102.

Which monomer is correctly matched with the type of bond that holds them together?

a)

lipid: carbohydrate covalent bonds

b)

monosaccharide: hydrogen and phosphodiester bonds

c)

nucleotide: ester linkages

d)

amino acids: peptide bonds

103.

Which functional group is NOT pictured in the image?

a)

phosphate

b)

amine

c)

hydroxyl

d)

carboxylic acid

104.

Which of the following statements is true?

a)

In order to create a polymer, a water is removed.

b)

In order to create a polymer, hydrolysis must occur.

c)

In order to create a polymer, a water is added.

d)

In order to create a polymer, oxygen must be present.

105.

The chromosomes that pair up during meiosis, are called __________ chromosomes.

a)

homozygous

b)

homologous

c)

asexual

d)

genes

106.

Which of the following factors does NOT determine the speed of diffusion?

a)

Temperature

b)

pH

c)

Diameter

d)

Concentration Gradients

107.

The cell that is pictured here in is what type of solution?

a)

Hypertonic

b)

Hypotonic

c)

Isotonic

d)

Hydrotonic

108.

What type of protein is labeled C?

a)

Peripheral protein

b)

Channel protein

c)

Integral protein

d)

Cholesterol

109.

Which of the following statements correctly matches a cell part with its function

a)

The cell membrane packages lipids for export

b)

The lysosome digests molecules

c)

The mitochondria perform photosynthesis

d)

The nucleus produces energy

110.

Keratin is a protein found in hair. Where in a cell is keratin made?

a)

Nucleus

b)

Golgi body

c)

Smooth ER

d)

Ribosome