Biological Molecules and Carbohydrates Quiz

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

Which of the following best describes a condensation reaction?

  • The cleaving of a large molecule into two smaller molecules.
  • The formation of a bond between two molecules with the removal of a water molecule. (correct)
  • The breaking of a bond by the addition of a water molecule.
  • The joining of two molecules with the direct release of oxygen.

Which of the following correctly pairs a disaccharide with its constituent monosaccharides?

  • Sucrose: galactose and fructose; Maltose: glucose and glucose; Lactose: fructose and glucose.
  • Sucrose: glucose and fructose; Maltose: glucose and glucose; Lactose: glucose and galactose. (correct)
  • Sucrose: glucose and fructose; Maltose: glucose and galactose; Lactose: glucose and glucose.
  • Sucrose: glucose and galactose; Maltose: glucose and fructose; Lactose: glucose and glucose.

What is the primary structural difference that leads to the distinct properties of cellulose compared to starch and glycogen?

  • Cellulose has many hydrogen bonds, while starch and glycogen have few.
  • Cellulose has peptide bonds, while starch and glycogen have glycosidic bonds.
  • Cellulose contains branching, while starch and glycogen are linear polymers.
  • Cellulose is made from β-glucose, while starch and glycogen are made from α-glucose. (correct)

Which statement accurately describes the structure of a triglyceride molecule?

<p>It is formed from a glycerol molecule bonded to three fatty acids via ester bonds. (C)</p> Signup and view all the answers

In the context of protein structure, which of the following best describes the role of hydrogen bonds?

<p>They contribute to the secondary and tertiary structures of proteins, by forming weaker links via polar interactions. (A)</p> Signup and view all the answers

What molecule forms the backbone of a phospholipid, as indicated by label A?

<p>Glycerol (D)</p> Signup and view all the answers

What type of bond links the glycerol molecule to a fatty acid in a phospholipid?

<p>Ester bond (B)</p> Signup and view all the answers

Which of the following correctly identifies an unsaturated fatty acid?

<p>A fatty acid that has at least one double bond between carbon atoms in the hydrocarbon chain. (D)</p> Signup and view all the answers

If a cell membrane has a 60% phospholipid composition by mass, and the total lipid mass is 200mg, what is the mass of the phospholipids?

<p>120mg (C)</p> Signup and view all the answers

How many molecules are required to form a single triglyceride molecule?

<p>4 (D)</p> Signup and view all the answers

Which of these statements most accurately describes an unsaturated fatty acid?

<p>It has at least one carbon-to-carbon double bond in its hydrocarbon chain. (B)</p> Signup and view all the answers

Based on the provided data, what approximate percentage of the plasma membrane is composed of 'other' lipids in a red blood cell?

<p>14% (C)</p> Signup and view all the answers

What is the primary difference between a saturated and an unsaturated fatty acid at a molecular level?

<p>Unsaturated fatty acids contain at least one carbon-carbon double bond, while saturated fatty acids do not. (A)</p> Signup and view all the answers

What property of water allows it to buffer changes in temperature effectively?

<p>Relatively high specific heat capacity (A)</p> Signup and view all the answers

Why is water described as a polar molecule, and what significance does this have in biological systems?

<p>It forms hydrogen bonds with other polar molecules, acting as a solvent. (C)</p> Signup and view all the answers

What is the importance of water being a universal solvent in cells?

<p>It carries nutrients and facilitates metabolic reactions. (D)</p> Signup and view all the answers

How does water's high surface tension benefit organisms?

<p>It enables some insects to walk on water's surface. (B)</p> Signup and view all the answers

In metabolic reactions within cells, what dual role does water play?

<p>It serves as a solvent and participates in hydrolysis reactions. (A)</p> Signup and view all the answers

What is the primary property of phospholipids that contributes to forming a bilayer in cell membranes?

<p>They are amphipathic with polar and non-polar regions. (A)</p> Signup and view all the answers

How does the concentration of omega-3 fatty acids change after 140 days?

<p>It stabilizes at around 0.4%. (D)</p> Signup and view all the answers

What part of the phospholipid molecule is attracted to water?

<p>The phosphate group. (D)</p> Signup and view all the answers

What is the primary role of phospholipids in cellular membranes?

<p>To form a hydrophobic barrier between the cell's interior and exterior. (D)</p> Signup and view all the answers

Which of the following statements correctly contrasts triglycerides and phospholipids?

<p>Phospholipids have hydrophilic and hydrophobic parts, while triglycerides have only hydrophobic tails. (D)</p> Signup and view all the answers

What is the primary role of water being a universal solvent in organisms?

<p>It allows for the transport of ions and faster reactions. (C)</p> Signup and view all the answers

How does the structure of water contribute to its properties?

<p>Water molecules are polar, leading to unique interactions. (B)</p> Signup and view all the answers

What is one advantage of water's high heat capacity to organisms?

<p>It stabilizes internal temperatures for enzyme reactions. (B)</p> Signup and view all the answers

What does the term 'reactive' mean in relation to water's properties?

<p>It participates in hydrolysis and condensation reactions. (C)</p> Signup and view all the answers

Which statement best describes the significance of hydrogen bonds in water?

<p>They help maintain temperature stability in organisms. (A)</p> Signup and view all the answers

What effect does the latent heat of vaporization have on organisms?

<p>It helps animals cool down by utilizing heat energy. (A)</p> Signup and view all the answers

Which of the following accurately describes why water is considered a major component of cells?

<p>It serves as a solvent for biochemical reactions. (D)</p> Signup and view all the answers

Which statement about the bonding in water is true?

<p>Water molecules are linked by hydrogen bonds. (D)</p> Signup and view all the answers

What type of bond is formed between carbon atoms in a double bond?

<p>Covalent bond (C)</p> Signup and view all the answers

What is a significant caveat concerning the correlation observed between omega-3 fatty acid intake and coronary heart disease risk?

<p>Confounding factors may influence the results. (D)</p> Signup and view all the answers

What type of bond is identified as bond X in the structure of olestra?

<p>Glycosidic bond (B)</p> Signup and view all the answers

Which of the following best describes a triglyceride's composition compared to olestra?

<p>Contains fewer fatty acids and no sucrose. (A)</p> Signup and view all the answers

When forming one molecule of olestra, how many molecules of water are produced from the starting materials?

<p>9 (C)</p> Signup and view all the answers

What happens to the concentration of omega-3 fatty acids in cow's milk when they are fed corn instead of grass?

<p>It decreases significantly. (D)</p> Signup and view all the answers

What is a distinguishing feature of olestra compared to triglycerides?

<p>It has a sucrose backbone. (B)</p> Signup and view all the answers

What relationship was investigated concerning omega-3 fatty acids and heart disease?

<p>Relationship between omega-3 intake and heart disease prevention. (C)</p> Signup and view all the answers

Flashcards

Monomer

A small molecule that can join to form polymers.

Polymers

Large molecules made up of many monomers linked together.

Glycosidic Bond

A bond formed between monosaccharides during condensation to create carbohydrates.

Triglycerides

Lipids made of one glycerol and three fatty acids; store energy.

Signup and view all the flashcards

Protein Structure Hierarchy

The arrangement of proteins into primary, secondary, tertiary, and quaternary structures.

Signup and view all the flashcards

Phospholipid

A molecule made of glycerol, fatty acids, and a phosphate group.

Signup and view all the flashcards

Glycerol

A three-carbon molecule that forms part of a phospholipid.

Signup and view all the flashcards

Ester bond

A bond formed between glycerol and fatty acids in a lipid.

Signup and view all the flashcards

Unsaturated fatty acid

A fatty acid that contains one or more double bonds between carbon atoms.

Signup and view all the flashcards

Percentage of lipid mass

The proportion of each type of lipid by weight in a cell.

Signup and view all the flashcards

Triglyceride formation

A triglyceride is formed by the condensation of three fatty acid molecules and one glycerol molecule.

Signup and view all the flashcards

Omega-3 fatty acids

A type of unsaturated fatty acid recognized for health benefits.

Signup and view all the flashcards

Hydrocarbon chain

A chain of carbon atoms bonded with hydrogen, found in fatty acids.

Signup and view all the flashcards

Omega-3 concentration

The level of omega-3 fatty acids in a sample, noted to decrease rapidly initially, then stabilize at 0.4% after 140 days.

Signup and view all the flashcards

Amphipathic

Describes molecules like phospholipids that contain both hydrophilic (water-attracting) and hydrophobic (water-repelling) parts.

Signup and view all the flashcards

Hydrophobic

A property of molecules like fatty acids that repel water and do not mix with it.

Signup and view all the flashcards

Phospholipid bilayer

A double layer of phospholipids that forms the basic structure of cell membranes, creating a barrier between the interior and exterior of the cell.

Signup and view all the flashcards

Double bond(s)

Bonds between two carbon atoms represented as C=C.

Signup and view all the flashcards

Correlation vs. Causation

Correlation indicates a relationship but does not prove one causes the other.

Signup and view all the flashcards

Triglyceride structure

A lipid made of glycerol and three fatty acids, without sucrose.

Signup and view all the flashcards

Formation of olestra

Olestra is formed by attaching fatty acids to sucrose via condensation.

Signup and view all the flashcards

Water molecules in olestra formation

Nine water molecules are produced when one molecule of olestra is formed.

Signup and view all the flashcards

Impact of diet on milk

Cows' diet change from grass to corn affects omega-3 concentration in milk.

Signup and view all the flashcards

High Specific Heat Capacity

Water can absorb or release a lot of heat without changing temperature significantly.

Signup and view all the flashcards

Cohesion

Attraction between water molecules that helps them stick together.

Signup and view all the flashcards

Universal Solvent

Water can dissolve many substances due to its polarity.

Signup and view all the flashcards

Surface Tension

The strong intermolecular forces at the surface of water that create a 'film'.

Signup and view all the flashcards

Polar Molecule

A molecule with a slight positive charge on one side and a slight negative charge on the other, like water.

Signup and view all the flashcards

Calibration Curve

A graph used to determine the concentration of a substance by comparing absorbance values.

Signup and view all the flashcards

Benedict’s Solution

A reagent used to test for reducing sugars like glucose, changes color upon heating.

Signup and view all the flashcards

Covalent Bonds

Strong bonds formed by the sharing of electrons between atoms, such as in water molecules.

Signup and view all the flashcards

Hydrogen Bonds

Weak attractions between polar molecules, crucial for water's unique properties.

Signup and view all the flashcards

High Heat Capacity

Water's ability to absorb lots of heat energy without a significant temperature change, stabilizing environments.

Signup and view all the flashcards

Hydrolysis Reaction

A reaction involving the breaking of bonds through the addition of water; opposite of condensation.

Signup and view all the flashcards

Latent Heat of Vaporization

The energy required for water to convert from liquid to gas, important for cooling organisms.

Signup and view all the flashcards

Study Notes

Biological Molecules

  • Monomer: A small repeating molecule that combines to form a polymer.
  • Polymer: A large molecule made up of repeating smaller molecules (monomers.)
  • Polymerisation: The process of producing polymers.
  • Condensation: The process where two monomers join together with the removal of water, forming a bond.
  • Hydrolysis: The splitting of a polymer into monomers with the addition of water, breaking down a bond.
  • Metabolism: All chemical processes within an organism's cells.

Carbohydrates

  • Carbohydrates contain the elements C, H, and O.
  • General formula (CHâ‚‚O)â‚™
  • Monosaccharides: Isomers (same chemical formula, different structural formulas) that dissolve in water and are reducing sugars.
  • Examples of monosaccharides include: triose (3 carbons), pentose (5 carbons), hexose (6 carbons).
  • Alpha-glucose and beta-glucose are isomers of hexose.
  • Glycosidic bonds: Covalent bonds formed by condensation reactions that bond monosaccharides together to form disaccharides and polysaccharides.
  • Polysaccharides include starch, glycogen, and cellulose. Starch and glycogen are polymers of alpha-glucose used for energy storage, while cellulose, formed by beta-glucose, is structural.

Lipids

  • Lipids contain C, H, and O.
  • Insoluble in water (non-polar.)
  • Triglycerides: Formed by condensation between glycerol and three fatty acids. Saturated triglycerides contain only single bonds. Unsaturated triglycerides contain double or triple carbon bonds, which cause kinks in the fatty-acid chains. Phospholipids are made of glycerol, two fatty acids, and a phosphate group. They are amphipathic (both hydrophilic and hydrophobic.) Triglycerides are used for energy storage while phospholipids are a key component in plasma membranes.

Proteins

  • Proteins contain C, H, O, N, and sometimes S.
  • Amino acids: Building blocks of proteins. About 20 naturally occurring amino acids found commonly in organisms.
  • Protein structure: Primary (sequence of amino acids), secondary (alpha-helix or beta-sheet), tertiary (complex 3D folding of protein), quaternary (multiple polypeptide chains.)
  • Types of proteins: Globular and fibrous proteins have diverse functions including catalysis, structural support, and transport.

Water

  • Water is a polar molecule which can act as a universal solvent and is involved in hydrolysis and condensation reactions.
  • Properties of water include: high heat capacity, high latent heat of vaporisation, cohesion, and a polar nature, which is important to living organisms.

Testing for Biological Molecules

  • Qualitative Tests: Tests which give a visual result to determine the presence of a biological molecule.
  • Quantitative Tests: Tests that give a numerical measurement of a variable, which can be statistically analyzed.
  • Tests to identify biological molecules include: Biuret test for proteins, Benedict's test for reducing sugars, iodine test for starch, and emulsion test for lipids.

Polysaccharide Summary Sheet

  • Provides a table for organizing information about polysaccharides: name, location, function, monomer type, type of chemical bonds, and a general description.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

Biological Molecules_115650.pdf

More Like This

Use Quizgecko on...
Browser
Open
Browser
Browser