Biological Molecules Flashcards
What are monomers?
Small, basic molecular units that can join together to form polymers
Examples include amino acids, nucleotides, and monosaccharides.
What are polymers?
Large, complex molecules formed from long chains of monomers
Examples include proteins, nucleic acids, and polysaccharides.
What type of reaction is used to form polymers from monomers?
Condensation reaction
This reaction involves the removal of water.
What type of reaction breaks down polymers into monomers?
Hydrolysis reaction
This reaction involves the addition of water.
What are carbohydrates composed of?
Carbon, hydrogen, and oxygen
The general formula for carbohydrates is (CH2O)n.
What are the three main types of carbohydrates?
Monosaccharides, disaccharides, and polysaccharides
Each type varies in complexity and structure.
What is a monosaccharide?
The simplest form of carbohydrates, consisting of a single sugar unit
Examples include glucose and fructose.
What is a disaccharide?
A carbohydrate formed from two monosaccharides joined together
Examples include sucrose (glucose + fructose) and lactose (glucose + galactose).
What is a polysaccharide?
A carbohydrate composed of long chains of monosaccharide units
Examples include starch, glycogen, and cellulose.
What is the primary function of carbohydrates?
To provide energy and serve as structural components
They are also involved in cellular communication.
Fill in the blank: Starch is a storage polysaccharide found in _______.
Plants
It is composed of amylose and amylopectin.
Fill in the blank: Glycogen is a storage polysaccharide found in _______.
Animals
It is highly branched and serves as a quick energy source.
True or False: Cellulose is a polysaccharide that provides structural support in plant cell walls.
True
It is composed of unbranched chains of β-glucose units.
What role do glycoproteins play in biological systems?
They are involved in cell recognition and signaling
Glycoproteins are proteins with carbohydrate groups attached.
What are the building blocks of proteins?
Amino acids
There are 20 different amino acids that combine in various sequences to form proteins.
What type of bond forms between amino acids in proteins?
Peptide bond
This bond is formed through a condensation reaction.
Fill in the blank: The sequence of amino acids in a protein determines its _______.
Structure and function
Any change in the sequence can affect the protein’s activity.
What are the four main types of biological molecules?
Proteins, Carbohydrates, Lipids, Nucleic Acids
These molecules are essential for life and perform various functions in living organisms.
Define proteins.
Large, complex molecules made up of amino acids
Proteins serve as enzymes, structural components, and play roles in immune response.
What is the basic unit of carbohydrates?
Monosaccharides
Examples include glucose and fructose.
What are lipids primarily composed of?
Fatty acids and glycerol
Lipids include fats, oils, and steroids.
What are nucleic acids responsible for?
Storing and transmitting genetic information
The two main types are DNA and RNA.
Fill in the blank: The monomers of proteins are _______.
Amino acids
There are 20 different amino acids that combine in various ways to form proteins.
True or False: All lipids are soluble in water.
False
Lipids are generally hydrophobic and do not dissolve in water.
What type of bond forms between amino acids?
Peptide bond
Peptide bonds are formed through a dehydration reaction.
List the functions of carbohydrates.
- Energy source
- Structural components
- Cell recognition
Carbohydrates can be classified as monosaccharides, disaccharides, or polysaccharides.
Fill in the blank: The primary energy source for cells is _______.
Glucose
Glucose is a simple sugar used directly by cells for energy.
What are the two types of nucleic acids?
DNA and RNA
DNA stores genetic information while RNA plays a role in protein synthesis.
What is the structure of DNA?
Double helix
DNA consists of two strands that coil around each other.
Fill in the blank: The primary function of enzymes is to _______.
Catalyze biochemical reactions
Enzymes lower the activation energy required for reactions.
True or False: All proteins function as enzymes.
False
While many proteins act as enzymes, others have structural or transport roles.
What is the role of lipids in the cell membrane?
Forming a barrier that separates the interior of the cell from the outside environment
Phospholipids are a major component of cell membranes.
List the components of a nucleotide.
- A phosphate group
- A sugar
- A nitrogenous base
Nucleotides are the building blocks of nucleic acids.
Fill in the blank: Saturated fats contain _______ bonds between carbon atoms.
Single
Saturated fats are typically solid at room temperature.
What is the primary function of RNA?
To transfer genetic information from DNA to the ribosome for protein synthesis
RNA plays a crucial role in the process of translation.
What are lipids?
Lipids are a group of organic compounds that are insoluble in water but soluble in organic solvents.
Examples include fats, oils, waxes, and steroids.
What is the primary function of lipids in living organisms?
Energy storage, insulation, and forming cell membranes.
Lipids also play roles in signaling and acting as hormones.
What are triglycerides composed of?
Glycerol and three fatty acids.
Triglycerides are the main form of stored energy in animals.
What is the difference between saturated and unsaturated fatty acids?
Saturated fatty acids have no double bonds between carbon atoms; unsaturated fatty acids have one or more double bonds.
Saturated fats are typically solid at room temperature, while unsaturated fats are liquid.
What are phospholipids, and why are they important?
Phospholipids are lipids with a phosphate group that form the bilayer of cell membranes.
They have hydrophilic heads and hydrophobic tails, creating a barrier for cell integrity.
What role does water play in biological systems?
Water is a solvent, regulates temperature, and is involved in biochemical reactions.
It also provides structure to cells and organisms.
What are the unique properties of water?
Cohesion, adhesion, high specific heat, and density.
These properties are crucial for maintaining life and supporting biological processes.
What are inorganic ions?
Inorganic ions are charged particles that do not contain carbon and are essential for various biological functions.
Examples include sodium, potassium, calcium, and chloride ions.
Fill in the blank: Inorganic ions are important for _______.
cell signaling, enzyme function, and maintaining osmotic balance.
True or False: All lipids are fats.
False.
Lipids include fats, oils, waxes, and steroids, which have different structures and functions.
What is the significance of the hydrophobic and hydrophilic nature of phospholipids?
It allows them to form bilayers that create cell membranes, separating the interior of cells from the external environment.
What is the role of triglycerides in the body?
They serve as long-term energy storage and provide insulation and protection for organs.
What is meant by the term ‘high specific heat’ in relation to water?
Water can absorb a lot of heat without a significant increase in temperature, helping to regulate environmental temperatures.
Fill in the blank: Water’s _______ property allows it to stick to other substances.
adhesive
What is the role of sodium ions in biological systems?
Sodium ions are crucial for nerve impulse transmission and muscle contraction.
What is a key characteristic of saturated fats?
They have no double bonds in their fatty acid chains.
What are proteins made of?
Proteins are made of amino acids
There are 20 different amino acids that combine in various sequences to form proteins.
What is the primary structure of a protein?
The primary structure is the sequence of amino acids in a polypeptide chain
This sequence determines the protein’s unique characteristics.
What type of bond links amino acids together?
Peptide bonds
Peptide bonds form between the carboxyl group of one amino acid and the amino group of another.
What is the secondary structure of proteins?
The secondary structure refers to the folding or coiling of the polypeptide chain
Common forms include alpha helices and beta-pleated sheets.
Define tertiary structure in proteins.
The tertiary structure is the overall 3D shape of a protein
It results from interactions between the side chains of amino acids.
What is quaternary structure in proteins?
The quaternary structure is the arrangement of multiple polypeptide chains in a protein
Not all proteins have quaternary structure; it is present in those with more than one polypeptide.
What role do enzymes play in biological processes?
Enzymes act as catalysts to speed up chemical reactions
They lower the activation energy required for reactions.
True or False: All proteins are enzymes.
False
While many enzymes are proteins, not all proteins function as enzymes.
What factors can affect enzyme activity?
Factors include temperature, pH, and substrate concentration
Each enzyme has an optimal temperature and pH at which it functions best.
Fill in the blank: The functional region of an enzyme is called the _______.
active site
The active site is where the substrate binds to the enzyme.
What is denaturation in proteins?
Denaturation is the alteration of a protein’s structure due to external stress
This can be caused by heat, pH changes, or chemicals, leading to loss of function.
List the four levels of protein structure.
- Primary
- Secondary
- Tertiary
- Quaternary
Each level of structure is crucial for the protein’s function.
What is the function of structural proteins?
Structural proteins provide support and shape to cells and tissues
Examples include collagen and keratin.
What are transport proteins?
Transport proteins carry substances across cell membranes or throughout the body
Hemoglobin is a well-known transport protein that carries oxygen in the blood.
What is the role of antibodies in the immune system?
Antibodies identify and neutralize foreign objects like bacteria and viruses
They are specialized proteins produced by the immune system.
Define the term ‘enzyme specificity’.
Enzyme specificity refers to the ability of an enzyme to select for a particular substrate
This is due to the unique shape and chemical properties of the active site.
What are nucleic acids?
Nucleic acids are large biomolecules essential for all known forms of life. They include DNA and RNA.
What is the primary function of DNA?
The primary function of DNA is to store and transmit genetic information.
What is the role of RNA?
RNA plays a crucial role in translating genetic information from DNA into proteins.
What are the building blocks of nucleic acids?
The building blocks of nucleic acids are nucleotides.
What are the components of a nucleotide?
A nucleotide consists of a phosphate group, a sugar, and a nitrogenous base.
What are the four nitrogenous bases in DNA?
The four nitrogenous bases in DNA are adenine (A), thymine (T), cytosine (C), and guanine (G).
What is ATP?
ATP (adenosine triphosphate) is a nucleotide that serves as the primary energy carrier in cells.
How is energy released from ATP?
Energy is released from ATP when it is hydrolyzed to ADP (adenosine diphosphate) and inorganic phosphate.
What is the significance of ATP in cellular processes?
ATP is crucial for various cellular processes, including muscle contraction, nerve impulse propagation, and biosynthesis.
