BISC1111 Lab #2

A small molecule that can be bonded to other molecules to form a polymer.

monomer

A long-chain molecule formed when many smaller molecules (monomers) link together.

polymer

What does the prefix “poly-” mean?

Many.

Which macromolecule is NOT technically a polymer?

lipids are not technically polymers.

A substance used by an organism to survive, grow, and reproduce.

nutrient

Are “nutrient” and “macromolecule” synonymous?

nutrient is defined by its role in supporting an organism’s survival, growth, and reproduction, while a macromolecule refers to a large molecule.

The building (synthesis) of complex molecules from simpler molecules; it requires energy and is called constructive metabolism.

anabolism

What happens to energy during anabolic reactions

Energy is required/consumed to build complex molecules.

what type of metabolic process is making polymers from monomers?

Anabolic, because it builds larger molecules from smaller ones and requires energy.

The breakdown of complex molecules into simpler molecules, often releasing energy; it is called destructive metabolism.

catabolism

What happens to energy during catabolic reactions

energy is released when complex molecules are broken down, and some of this energy is captured as ATP.

Polymeric biological macromolecules made primarily of carbon (C), hydrogen (H), and oxygen (O).

carbohydrates

What is the typical C:H:O ratio in carbohydrates?

1:2:1

The monomers of carbohydrates; examples include glucose and fructose.

monosaccharides

The polymers of carbohydrates; examples include glycogen and cellulose.

polysaccharides

Are all carbohydrates sugars?

No. All sugars are carbohydrates, but not all carbohydrates are sugars

How much energy do carbohydrates provide?

4 calories per gram of carbohydrate.

What are the main functions of carbohydrates in living organisms?

catabolized for energy and used as storage and structural molecules.

What is the main energy-related role of carbohydrates?

They serve as the main energy source for most organisms.

What is an important structural role of carbohydrates?

They provide structure in plants.

What are the three major types of lipids?

Fats, phospholipids, and steroids.

what are the main functions of lipids?

Energy storage and membrane formation.

Are lipids polymers?

No. Lipids are not technically polymers.

Are triglycerides made from smaller component molecules?

Yes. Although triglycerides are not polymers, they are made from smaller components.

Why are triglycerides important for energy storage?

they are energy-dense, providing 9 calories per gram

What is the physical state of unsaturated fats at room temperature?

Liquid

What is the physical state of saturated fats at room temperature?

Solid.

What is a triglyceride made of?

1 glycerol molecule + 3 fatty acid chains.

What is the main structural role of phospholipids?

They form the phospholipid bilayer, the main structural component of cell membranes.

How does the phospholipid bilayer help cells maintain homeostasis?

It is semi-permeable, allowing the cell to control what enters and leaves in different environments.

What is cholesterol's role in the body?

vital lipid but is not broken down for energy like triglycerides.

How are trans fats produced?

They are made artificially through a partial hydrogenation process

saturated fat carbon bonds

single carbon bonds

unsaturated carbond bonds

double bond

trans fat carbon bonds

trans double bond

What are the four main components attached to the central carbon of an amino acid?

amino group, carboxyl group, hydrogen atom, and R group (side chain).

the part of an amino acid that varies between the 20 amino acids and determines their unique properties.

R group (side chain)

What properties can amino acid side chains determine

Properties such as solubility, acidity, and electrical charge.

What are chains of amino acids called?

Polypeptides.

What part of an amino acid is identical across all 20 amino acids?

The amino group, carboxyl group, hydrogen atom, and central carbon are the same; the R group is what differs.

What are the four levels of protein structure?

Primary, secondary, tertiary, and quaternary. only some have quaternary structure.

The linear sequence of amino acids in a polypeptide.

primary structure of protein

The protein's final three-dimensional shape, created by interactions and bonds between amino acid side chains (R groups).

tertiary structure of a protein

The organization formed when two or more polypeptide chains bond together to create a functional protein

quaternary structure

Do all proteins have quaternary structure?

No. Only proteins made of two or more polypeptide chains have quaternary structure

What is an example of a protein with quaternary structure?

Hemoglobin

What determines the function of a protein?

Its 3D structure (shape) determines its function.

A specific type of protein that catalyzes chemical reactions by lowering the activation energy required for the reaction to occur.

enzyme

Is an enzyme used up during the chemical reaction it catalyzes?

no

What does it mean that enzymes are specific?

Each enzyme typically catalyzes a very specific chemical reaction involving a particular substrate.

A process where the final product of a pathway inhibits the formation of more of that product, helping regulate the pathway.

negative feedback loop

A molecule made of 2 linked components.

dimer

What are examples of carbohydrate dimers (disaccharides)?

Lactose and sucrose.

What are examples of carbohydrate polymers?

Starch and cellulose.

What are the components of a triglyceride?

Fatty acids and glycerol. They are components, not monomers, because triglycerides are not polymers.

What are examples of larger lipid molecules?

Triglycerides, saturated fats, unsaturated fats, and trans fats, but these are not true polymers.

What are the monomers of proteins?

Amino acids.

A molecule made of 2 amino acids linked together.

dipeptide

What are the monomers of nucleic acids?

Nucleotides.

A molecule made of 2 linked nucleotides.

dinucleotide

What are the polymers of nucleic acids?

DNA and RNA.

contains at least one carbon atom covalently bonded to one or more hydrogen atoms.

organic molecule

A strong chemical bond in which at least two atoms are linked by sharing electrons.

covalent bond

How are monomers linked together to form polymers?

Through covalent bonds between the smaller repeating units.

Distinct arrangements of specific atoms attached to organic molecules that influence their chemical properties and functions.

functional groups

How do functional groups affect macromolecules?

influence a molecule's overall chemical properties and roles within cells.

Why must large macromolecules be broken down during digestion?

They are too large to cross the plasma membrane, so digestion breaks them into smaller components that can be absorbed.

What happens to macromolecule components after they are absorbed?

Cells can use them to build new molecules through metabolism.

What is the main function of DNA and RNA?

store and transport genetic information.

What is the role of ATP?

ATP provides usable energy for cellular processes.

How do carbohydrates and lipids differ in energy storage?

Carbohydrates are mainly used for short-term energy storage, while lipids are mainly used for long-term energy storage.

What is a nutrient that organisms need in relatively small amounts?

Vitamins and minerals.

What does the term "sugar" generally refer to in biology?

Small carbohydrates such as glucose, fructose, and sucrose.

What is the molecular formula commonly used to represent the basic carbohydrate unit?

CH₂O.

It provides a readily available source of energy and can also be used to build larger carbohydrates.

glucose

A glucose-based polysaccharide that forms structural material in fungal cell walls.

chitin

A glucose-based polysaccharide that forms a major structural component of plant cell walls.

cellulose

A glucose polymer used by plants for energy storage.

starch

A glucose polymer used by animals for energy storage.

glycogen

Why are cellulose and chitin generally considered dietary fiber?

Humans generally cannot digest their chemical bonds, so they pass through the digestive system largely undigested.

How does insoluble fiber benefit the digestive system?

It promotes intestinal health and helps maintain normal movement through the digestive tract.

Why are lipids generally hydrophobic?

their structures contain many nonpolar carbon-hydrogen bonds that do not interact well with water.