AP Bio Unit 1 Flashcards

What is polarity?

It is a property of molecules that have a distribution of electrical charge, leading to distinct positive and negative ends.

What is hydrogen bonding in water?

Hydrogen bonding is the attraction between the positively charged hydrogen atoms of one water molecule and the negatively charged oxygen atoms of another.

What is cohesion?

Cohesion refers to the tendency of molecules to stick together due to similar intermolecular forces.

What is adhesion?

Adhesion is the attraction between different types of molecules, often allowing water to cling to surfaces.

What is surface tension?

Surface tension is the cohesive force at the surface of a liquid that makes it behave like a stretched elastic membrane.

What are macromolecules?

Macromolecules are large, complex molecules such as proteins, nucleic acids, carbohydrates, and lipids.

What are atoms?

Atoms are the basic units of matter and the defining structure of elements.

What are molecules?

Molecules are two or more atoms bonded together, representing the smallest fundamental unit of a chemical compound.

What is carbon?

Carbon is a fundamental building block of life, known for its ability to form four covalent bonds.

What is nitrogen?

Nitrogen is a key element found in amino acids and nucleic acids, crucial for life.

What are carbohydrates?

Carbohydrates are organic compounds made up of carbon, hydrogen, and oxygen, functioning primarily as energy sources.

What are proteins?

Proteins are large molecules composed of one or more chains of amino acids, essential for countless biological processes.

What are lipids?

Lipids are a diverse group of hydrophobic molecules, including fats, oils, and phospholipids.

What are nucleic acids?

Nucleic acids, such as DNA and RNA, are macromolecules composed of nucleotide chains that store and transmit genetic information.

What is phosphorus?

Phosphorus is an essential element in various biological molecules, including nucleic acids and ATP.

What are monomers?

Monomers are the basic building blocks that join together to form polymers.

What is hydrolysis?

Hydrolysis is a chemical reaction in which water is used to break down the bonds of a particular substance.

What is dehydration synthesis?

Dehydration synthesis is a reaction that combines two molecules, releasing water in the process.

What is a polypeptide?

A polypeptide is a chain of amino acids linked by peptide bonds, constituting a section of a protein.

What is primary structure?

The primary structure of a protein refers to its unique sequence of amino acids.

What is directionality in proteins?

Directionality refers to the orientation of a protein, indicated by the positioning of the amino and carboxyl termini.

What is amino terminus?

The amino terminus, or N-terminus, is the end of a protein or polypeptide that has a free amino group.

What is carboxyl terminus?

The carboxyl terminus, or C-terminus, is the end of a protein or polypeptide that has a free carboxyl group.

What is an R group?

An R group, or side chain, is the part of an amino acid that varies among different amino acids and determines their characteristics.

What are ionic bonds?

Ionic bonds are a type of chemical bond formed between two ions with opposite charges.

What is secondary structure?

Secondary structure refers to the localized folding of polypeptides into structures like alpha-helices and beta-sheets.

What is tertiary structure?

Tertiary structure describes the overall three-dimensional shape of a polypeptide chain, determined by interactions among various R groups.

What is quaternary structure?

Quaternary structure is the arrangement of multiple polypeptide chains forming a functional protein complex.

What is an unsaturated fatty acid?

An unsaturated fatty acid contains one or more double bonds in its hydrocarbon chain, resulting in fewer hydrogen atoms.

What is a saturated fatty acid?

A type of fat in which each carbon atom is bonded to as many hydrogen atoms as possible, resulting in no double bonds.

What are phospholipids?

A class of lipids that are a major component of all cell membranes, consisting of a hydrophilic 'head' and two hydrophobic 'tails'.

What is the polar region of a molecule?

The part of a molecule that has a partial positive charge and a partial negative charge, making it water-soluble.

What is a nonpolar region?

The part of a molecule that lacks charge and does not interact well with water, making it hydrophobic.

What are polymers?

Large molecules composed of repeating structural units (monomers) connected by covalent bonds.

What does nonpolar mean?

Describes molecules or regions of molecules that do not have distinct positive and negative poles, making them hydrophobic.

What does hydrophobic mean?

A property of substances that do not mix well with or are repelled by water.

What does hydrophilic mean?

A property of substances that can readily interact with or dissolve in water

What are nucleic acids?

Biopolymers essential for all forms of life, primarily DNA and RNA, that store and transmit genetic information.

What is a five-carbon sugar?

A sugar molecule containing five carbon atoms, which is a component of nucleotides in nucleic acids.

What is deoxyribose?

A five-carbon sugar that is a component of DNA, lacking one oxygen atom compared to ribose.

What is ribose?

A five-carbon sugar that is a component of RNA, crucial for the formation of RNA nucleotides.

What is a phosphate group?

A chemical group consisting of a phosphorus atom bonded to four oxygen atoms, key in the backbone of nucleic acids and ATP.

What is a nitrogen base?

Molecules that contain nitrogen and act as the building blocks of nucleic acids; examples include adenine, thymine, guanine, cytosine, and uracil.

What does DNA stand for?

Deoxyribonucleic acid, the molecule that carries genetic information in living organisms.

What does RNA stand for?

Ribonucleic acid, a molecule that plays roles in coding, decoding, regulation, and expression of genes.

What is the 3’ hydroxyl end?

The end of a DNA or RNA strand where a hydroxyl group (-OH) is attached to the third carbon of the sugar.

What is the 5’ phosphate end?

The end of a DNA or RNA strand where a phosphate group is attached to the fifth carbon of the sugar.

What does antiparallel mean in DNA?

Refers to the two strands of DNA running in opposite directions; one strand runs 5’ to 3’ and the other runs 3’ to 5’.

What is a double helix?

The structure formed by double-stranded DNA, resembling a twisted ladder.

What are the base pairing rules for DNA?

Adenine pairs with thymine (A-T) and cytosine pairs with guanine (C-G) in DNA.

How many hydrogen bonds form between A and T?

Two hydrogen bonds.

How many hydrogen bonds form between C and G?

Three hydrogen bonds.

What are alpha-helices?

A common protein secondary structure characterized by a right-handed coil.

What are beta-sheets?

Another common protein secondary structure consisting of beta strands connected laterally by hydrogen bonds.

What are carbohydrate polymers?

Polymers made of sugar monomers that can be linear or branched, such as starch and glycogen