Macromolecules and Nucleic Acids (Video Note) 4 Biology HS

Practice flashcards covering macromolecules (carbohydrates, lipids, proteins, nucleic acids), their structure, detection methods, functions, and examples as presented in the video notes.

major macromolecule groups

Carbohydrates, lipids, proteins, and nucleic acids (also called biomolecules).

polymerization

The process of joining monomers to form large polymers.

monomer

A subunit or building block that links together to form polymers.

Where do cellulose microfibrils occur in cells?

In the plant cell wall as part of carbohydrates.

elements that make up carbohydrates and the polymers there

Carbohydrates are made of carbon, hydrogen, and oxygen; polysaccharides are polymers formed from monosaccharides.

monosaccharides?

The simple sugar building blocks of carbohydrates.

polysaccharides?

Polymers made up of many monosaccharides (complex sugars).

main function(s) of carbohydrates in organisms

Primary source of immediate energy and also structural roles.

How to detect simple sugars in lab

Benedict’s solution turns orange in the presence of simple sugars.

How to detect starches in lab

Iodine or Lugol’s solution turns deep purple in the presence of starch.

basic lipid structure

Lipids are made of glycerol and fatty acids; they have hydrophobic tails and a hydrophilic head, and include phospholipids.

two main components of many lipids?

Glycerol and fatty acids.

What distinguishes saturated and unsaturated fatty acids?

Saturated fats have no double bonds; unsaturated fats have one or more double bonds.

What role do phospholipids play in cell membranes?

They form the cell membrane with a hydrophilic head and hydrophobic tails.

lipid functions

Store energy, form cell membranes, and provide waterproof coverings.

How to detect lipids

Brown paper bag test leaves a translucent spot if lipids are present.

elements that make up proteins

Carbon, hydrogen, oxygen, and nitrogen.

amino acids

The building blocks of proteins; there are over 20 different amino acids.

main functions of proteins

Enzymes speed up reactions; form muscles; transport substances; fight disease.

examples of proteins and their roles

Hemoglobin carries oxygen in red blood cells; insulin regulates blood sugar.

How to detect proteins

Biuret’s solution turns blue to light purple in the presence of protein.

elements and monomers of nucleic acid

Nucleic acids are made of carbon, hydrogen, oxygen, nitrogen, and phosphorus; subunits are nucleotides.

function of nucleic acids

Store and transmit hereditary information.

two main nucleic acids

DNA and RNA.

What is the structure of DNA and how does it differ from RNA in sugar?

DNA has a double helix with deoxyribose sugar; RNA is typically single-stranded with ribose sugar (and contains uracil).

What are the three main types of RNA?

Messenger RNA (mRNA), ribosomal RNA (rRNA), and transfer RNA (tRNA).

What is a nucleosome?

DNA wrapped around histone proteins, forming a basic unit of chromosome structure.

What is the backbone of DNA/RNA?

The sugar-phosphate backbone.

What is base pairing in nucleic acids?

Complementary bases pair to hold the two strands together (A with T or U, C with G).

What is the sugar in DNA versus RNA nucleotides?

DNA contains deoxyribose; RNA contains ribose.