IB Program Biology: B1.1 Carbohydrates and Lipids Review

How many covalent bonds does carbon form, allowing for the creation of complex and stable molecules?

4 covalent bonds

What are the five main elements that carbon can bond with to form diverse biomolecules?

CHONP

What characteristic of carbon allows for long chains, branches, rings, and overall biomolecule diversity?

Carbon's bonding versatility

What term refers to very large molecules with a molecular mass greater than 10,000 amu?

macromolecules

What is a small subunit that can join with others to form a chain (polymer)?

monomer

What is a long chain of monomers linked together?

polymer

What type of reaction joins molecules together while removing a water molecule (H2O)?

condensation reaction

What type of bonds join glucose monomers together to form polysaccharides?

glycosidic bonds

What specific bonds form the straight chains in polysaccharides?

1->4 glycosidic bonds (#refer to which carbon bonds to which carbon)

What specific bonds create branches in polysaccharides?

1->6 glycosidic bonds (#refer to which carbon bonds to which carbon)

What reaction breaks down polymers into monomers by adding water?

hydrolysis

During what process is hydrolysis used to break down polysaccharides, proteins, and nucleic acids?

digestion of macromolecules

What are the monomer products when polysaccharides undergo hydrolysis?

monosaccharides

What are the monomer products when polypeptides undergo hydrolysis?

amino acids

What are the monomer products when nucleic acids undergo hydrolysis?

nucleotides

How many carbon atoms are typically found in a monosaccharide molecule?

3-7 carbon atoms

what is a 5-carbon monosaccharide called?

pentose

What is a 6-carbon monosaccharide called?

hexose

What molecular shape must pentose and hexose sugars usually form in order to build larger carbohydrates?

ring form

Which small, highly soluble sugar is easily transported in blood and used as the primary substrate for respiration?

glucose

osmotic problems

free glucose molecules disrupt cell water balance, react with other cellular chemicals, and take up too emuch space

Why is glucose usually converted to starch or glycogen for storage instead of being stored as free glucose?

osmotic problems

Which polysaccharide is used for energy storage in plants and is made of alpha-glucose?

starch

Which polysaccharide is used for energy storage in animals, is made of alpha-glucose, and is more highly branched than amylopectin?

glycogen

Which component of starch is an unbranched, helical chain of alpha-glucose with 1->4 bonds?

amylose

Which component of starch is branched, containing both 1->4 and 1->6 bonds (with 1 branch per 20 subunits)?

amylopectin

What feature of polysaccharides provides more ends where glucose can be added or removed quickly?

branching

Why can large polysaccharides store lots of glucose without greatly increasing the cell's osmotic concentration?

low solubility

Which unbranched polysaccharide provides structural support in plant cell walls and is made of beta-glucose?

cellulose

What structural arrangement of beta-glucose molecules in cellulose allows them to form straight, unbranched chains?

alternating inversion

What forms between neighboring straight chains of cellulose, allowing them to align parallel?

hydrogen bonds

What high-tensile-strength structures are formed by groups of parallel cellulose chains?

microfibrils

What molecule consists of a polypeptide bonded to a short carbohydrate chain (oligosaccharide)?

glycoprotein

Where are glycoproteins positioned in animal cells, allowing them to act as cell-recognition markers?

Facing outwards on plasma membranes

What are three important biological roles of glycoproteins?

Tissue organization, identifying foreign cells, identifying and destroying infected cells

What is a well-known example of glycoprotein markers used in cell recognition?

ABO blood-group antigens

What term describes lipids because they are poorly soluble in water and more attracted to non-polar solvents?

Hydrophobic

What are the four main classes of lipids?

Fats, oils, waxes, and steroids

What differs between the four main classes of lipids?

Melting points

Which lipids are made from 1 glycerol and 3 fatty acids , and are linked by ester bonds?

Triglycerides

How many water molecules are produced during the condensation reactions that form a single triglyceride

3 H2O; because 3 rxns occur

Are triglycerides hydrophobic or hydrophilic, and why?

Hydrophobic because their hydrophilic groups are used in the reactions

Which lipids consist of 1 glycerol, 2 fatty acids, and 1 phosphate group?

Phospholipids

What property does the phosphate group of the phospholipid have?

Hydrophilic head

What property do the fatty acid chains of a phospholipid have?

Hydrophobic tails

What word is used to describe a molecule like a phospholipid that has hydrophilic and hydrophobic areas?

Amphiatic

What structure naturally forms in water when hydrophilic heads face outward and hydrophobic tails face inward?

Phospholipid bilayer

What is the typical range of carbon atoms in the hydrocarbon chains of biological fatty acids?

14-20 carbons

Which fatty acids have only single (C-C) carbon-carbon bonds and the maximum number of hydrogens?

Saturated fatty acids

Which fatty acids contain exactly 1 carbon bond in their hydrocarbon chain?

Monosaturated fatty acids

Which fatty acids contain 2 or more doubles bonds in their hydrocarbon chain?

Polysaturated fatty acids

Which type of unsaturated fatty acid have the hydrogens on the same side of the double bond, causing a bend?

Cis-fatty acid

Which type of unsaturated fatty acid have the hydrogens on opposite sides of the double bond, leaving the chain straight?

Trans-fatty acids

Which type of fat has a lower melting point because its bent chains pack less tightly together?

Cis-unsaturated fats

Where are triglycerides stored in animals?

Adipose tissue

What are 3 terms to describe characteristics of lipids?

Energy storage, insulation, buoyancy

How much more energy do triglycerides release compared to carbs, making them excellent for long-term energy storage?

About 2x more energy per gram

What property allows triglycerides to form droplets and be stored without causing major osmotic effects?

Water immiscibility

Besides energy storage, what are two key physical functions of triglycerides?

Thermal insulation and shock absorption

Which active animals particularly benefit from the efficient energy storage of triglycerides?

Birds and Bats

What major cellular structures are composed of phospholipids?

Cell membranes

Which hydrophobic lipids can pass directly through the cell's phospholipid bilayer?

Steroids