Hydrolysis; addition of water to break bonds ($$\text{Polymer} + \text{H}_2\text{O} \rightarrow \text{Monomer}_1 + \text{Monomer}_2)$$

Question 1

Which process is responsible for breaking down polymers into monomers, and what is the chemical reaction involved?

Accepted Answer

Hydrolysis; addition of water to break bonds ($$	ext{Polymer} + 	ext{H}_2	ext{O} ightarrow 	ext{Monomer}_1 + 	ext{Monomer}_2)$$

Question 2

Which of the following best explains why polysaccharides such as starch and glycogen are effective for energy storage in cells?

Accepted Answer

They are composed of monosaccharides linked by glycosidic bonds, allowing rapid hydrolysis when energy is needed.

Question 3

A triglyceride contains fatty acids that are all saturated. Which property would you expect this molecule to have at room temperature?

Accepted Answer

It would be solid due to straight chains that pack tightly.

Question 4

Which of the following statements about phospholipids is correct?

Accepted Answer

They have a hydrophilic head and two hydrophobic tails, allowing them to form bilayers in water.

Question 5

How does the sequence of amino acids in a protein determine its tertiary structure?

Accepted Answer

The sequence determines the chemical properties of side chains, which interact to fold the protein into its three-dimensional shape.

Question 6

Which of the following is a function of enzymes in metabolic reactions?

Accepted Answer

They lower the activation energy ($$E_a) $$required for a reaction to proceed.

Question 7

A mutation changes the sequence of a protein, causing it to misfold. What is a likely consequence for the cell?

Accepted Answer

The protein may lose its function, potentially leading to disease or cell death.

Question 8

Which of the following best describes the difference between DNA and RNA nucleotides?

Accepted Answer

DNA contains deoxyribose sugar and thymine, while RNA contains ribose sugar and uracil.

Question 9

Which base pairing occurs in DNA, and what is the chemical basis for this specificity?

Accepted Answer

Adenine pairs with thymine via two hydrogen bonds; guanine pairs with cytosine via three hydrogen bonds.

Question 10

Which organelle is responsible for protein synthesis in eukaryotic cells?

Accepted Answer

Ribosome

Question 11

What is the main function of the endomembrane system in eukaryotic cells?

Accepted Answer

It regulates protein traffic and performs metabolic functions, including synthesis, modification, and transport of proteins and lipids.

Question 12

A cell is observed to have a large number of smooth endoplasmic reticulum. What is a likely function of this cell?

Accepted Answer

Synthesis of lipids and detoxification of drugs

Question 13

Which of the following best explains the role of peroxisomes in the cell?

Accepted Answer

They break down fatty acids and detoxify harmful substances using hydrogen peroxide ($$	ext{H}_2	ext{O}_2).$$

Question 14

How does the cytoskeleton contribute to muscle contraction?

Accepted Answer

Microfilaments (actin) interact with myosin to produce contraction.

Question 15

Which of the following is a key difference between prokaryotic and eukaryotic cells?

Accepted Answer

Eukaryotic cells have internal membranes that compartmentalize functions; prokaryotic cells do not.

Question 16

A scientist discovers a new cell type with extensive Golgi apparatus. What is a likely function of this cell?

Accepted Answer

Modification, sorting, and packaging of proteins for secretion

Question 17

Which of the following statements about genomics and proteomics is correct?

Accepted Answer

They have transformed biological inquiry by allowing the study of entire sets of genes and proteins, aiding in disease research.

Question 18

Which chemical property of the R-group in amino acids most directly affects protein folding?

Accepted Answer

Polarity and charge, which influence interactions such as hydrogen bonding and ionic interactions

Question 19

Which of the following best describes the function of lysosomes in animal cells?

Accepted Answer

They contain hydrolytic enzymes that digest macromolecules and recycle cellular components.

Macromolecules, Cell Structure, and Function: Study Guide (Chapters 5 & 6)

Guida di studio - Domande di pratica