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Question 1

Blue Word

Answer 1

Definition

Question 2

prokaryote

Answer 2

A single-celled organism without a nucleus or membrane-bound organelles (e.g., bacteria and archaea).

Question 3

eukaryote

Answer 3

A cell or organism that contains a nucleus and membrane-bound organelles.

Question 4

bacteria

Answer 4

A domain of prokaryotic microorganisms that can be beneficial or pathogenic.

Question 5

plasma membrane

Answer 5

A selectively permeable lipid bilayer that surrounds the cell, controlling what enters and exits.

Question 6

cytoplasm

Answer 6

The gel-like substance within a cell that contains organelles, enzymes, and molecules necessary for cellular function.

Question 7

cytosol

Answer 7

The aqueous component of the cytoplasm where organelles and molecules are suspended.

Question 8

organelles

Answer 8

Specialized structures within a eukaryotic cell that perform distinct functions.

Question 9

nucleus

Answer 9

The control center of the eukaryotic cell, housing DNA and regulating gene expression.

Question 10

nuclear envelope

Answer 10

A double membrane that surrounds the nucleus, separating it from the cytoplasm.

Question 11

nuclear pore

Answer 11

Protein-lined channels in the nuclear envelope that allow the transport of molecules between the nucleus and cytoplasm.

Question 12

chromosomes

Answer 12

Thread-like structures of DNA and protein that contain genetic information.

Question 13

endoplasmic reticulum

Answer 13

A network of membranes involved in protein and lipid synthesis; includes rough ER (with ribosomes) and smooth ER (without ribosomes).

Question 14

lysosomes

Answer 14

Membrane-bound organelles that contain digestive enzymes to break down waste and cellular debris.

Question 15

hydrolase

Answer 15

An enzyme that catalyzes the hydrolysis of a chemical bond.

Question 16

mitochondria

Answer 16

The powerhouse of the cell, generating ATP through cellular respiration.

Question 17

peptide bonds

Answer 17

Covalent bonds that link amino acids together in proteins.

Question 18

N-terminus

Answer 18

The end of a polypeptide with a free amino group (-NH2).

Question 19

C-terminus

Answer 19

The end of a polypeptide with a free carboxyl group (-COOH).

Question 20

polypeptide

Answer 20

A chain of amino acids linked together by peptide bonds.

Question 21

polypeptide backbone

Answer 21

The repeating sequence of atoms in a polypeptide chain, excluding the side chains.

Question 22

disulfide bond

Answer 22

A strong covalent bond formed between sulfur atoms of two cysteine amino acids.

Question 23

hydrogen bonds

Answer 23

Weak bonds between partially positive hydrogen and electronegative atoms (e.g., oxygen, nitrogen).

Question 24

ionic bonds

Answer 24

Electrostatic attraction between oppositely charged ions in proteins.

Question 25

Van der Waals forces

Answer 25

Weak interactions between molecules due to temporary dipoles.

Question 26

secondary structure

Answer 26

Local folding patterns in a protein, including alpha helices and beta sheets.

Question 27

tertiary structure

Answer 27

The overall 3D shape of a single polypeptide due to interactions between side chains.

Question 28

protein domains

Answer 28

Distinct functional or structural units in a protein.

Question 29

enzyme

Answer 29

A protein that speeds up biochemical reactions by lowering activation energy.

Question 30

active site

Answer 30

The region on an enzyme where the substrate binds and a reaction occurs.

Question 31

induced fit model

Answer 31

A model where an enzyme changes shape to better fit its substrate.

Question 32

conformational change

Answer 32

A structural change in a protein that affects its function.

Question 33

kinase

Answer 33

An enzyme that adds a phosphate group to a protein.

Question 34

phosphatase

Answer 34

An enzyme that removes a phosphate group from a protein.

Question 35

phosphorylation

Answer 35

The addition of a phosphate group to a molecule, often regulating protein activity.

Question 36

purines

Answer 36

Double-ring nitrogenous bases (adenine, guanine) in nucleic acids.

Question 37

pyrimidines

Answer 37

Single-ring nitrogenous bases (cytosine, thymine, uracil) in nucleic acids.

Question 38

nucleotide

Answer 38

The building block of nucleic acids, consisting of a sugar, phosphate, and nitrogenous base.

Question 39

dNTP

Answer 39

Deoxyribonucleotide triphosphates used as DNA building blocks during replication.

Question 40

NTP

Answer 40

Nucleoside triphosphates used in RNA synthesis.

Question 41

phosphodiester bond

Answer 41

The bond linking nucleotides in a DNA or RNA strand.

Question 42

5’

Answer 42

The end of a nucleic acid strand with a phosphate group on the 5' carbon of the sugar.

Question 43

3’

Answer 43

The end of a nucleic acid strand with a hydroxyl group on the 3' carbon of the sugar.