Cellular Communication Lecture 1

Ways living cells in an organism communicate, either directly or through chemical signals (like neurotransmitters, hormones, and cAMP).

Cells communicate by direct contact of surface molecules.

Signals affect nearby cells only.

Cells respond to molecules they produce themselves.

Hormones from glands travel through the bloodstream to distant cells.

Receptors inside the cell, for hydrophobic signaling molecules that can cross the membrane.

Receptors on the cell surface; for hydrophilic signaling molecules that can't cross the membrane.

Molecules that can dissolve in fats and pass through cell membranes easily.

A sugar acid formed by oxidizing the 6th carbon (last hydroxyl group) of an aldose, creating a carboxyl group.

Di-carboxylic acid formed by oxidizing both the carbonyl group (1st carbon) and the last hydroxyl group (6th carbon) of an aldose to carboxylic acids.

A sugar where a hydroxyl group (OH) has been replaced by a hydrogen atom (H).

A sugar where a hydroxyl group has been replaced by an amino (NH2) group.

A covalent bond linking a carbohydrate molecule to another molecule, often another carbohydrate.

A disaccharide formed by two glucose molecules linked by an α(1→4) glycosidic bond.

A disaccharide formed by two glucose molecules linked by an α(1→6) glycosidic bond.

A disaccharide formed by one glucose and one galactose molecule linked by a β(1→4) glycosidic bond.

Simple sugars with 3 carbon atoms and the chemical formula C3H6O3. They are the smallest monosaccharides.

A triose with a ketone group, making it a ketose. Its structure features two hydroxyl groups (OH) attached to the carbon chain.

Carbon atoms in monosaccharides are numbered starting from the aldehyde group (for aldoses) or the ketone group (for ketoses).

Most monosaccharides with 5 or more carbons exist in a ring form where the aldehyde or ketone group reacts with an alcohol on the same sugar molecule.

Produced by reducing the carbonyl group of a sugar to a hydroxyl group, resulting in a sugar alcohol.

Sugars can be oxidized to form acids. Aldonic acids are formed by oxidizing the aldehyde group, while uronic acids are formed by oxidizing the last hydroxyl group.

A disaccharide composed of two glucose molecules linked by a β-(1→4) glycosidic bond. It is a product of partial hydrolysis of cellulose.

A carbohydrate made up of long chains of repeating sugar units linked together by glycosidic bonds. They serve as energy storage or structural components.

Polysaccharides that are stored in organisms as energy reserves. Examples include starch, glycogen, and inulin.

A major storage polysaccharide in plants, composed of two components: amylose (linear chains of glucose) and amylopectin (branched chains of glucose).

A highly branched polysaccharide that serves as the primary energy storage molecule in animals. Similar to amylopectin but with more branches.

A structural polysaccharide found in plant cell walls, comprised of long, straight chains of glucose molecules linked by β-(1→4) glycosidic bonds. It provides rigidity and strength to plants.

A polysaccharide composed entirely of fructose units. Found in some plants, it's used in diagnostic tests for kidney function.

Storage polysaccharides act as energy reserves for organisms, while structural polysaccharides provide structural support.

A complex carbohydrate made up of different types of sugar monomers. Examples include pectins, gum arabic, and agar-agar.

Structural polysaccharides found in fruits. They break down into galactose, arabinose, and galacturonic acid.

A heteropolysaccharide containing galactose and glucuronic acid, often used as a food additive.

A polysaccharide made up of galactose, derived from seaweed. It's used as a culture medium for bacteria.

A protein molecule with a small amount of carbohydrates attached. It plays important roles in immunity, cell recognition, and other biological processes.

Organic compounds composed of carbon, hydrogen, and oxygen, typically with the general formula Cn(H2O)n. They are polyhydroxy aldehydes or ketones, or compounds yielding them upon hydrolysis.

Carbohydrates serve as a primary energy source for the body, providing about 50% of its energy needs. They also contribute to the structure of cells and tissues, play a role in cellular signaling, and regulate intestinal movement.

Simple sugars that cannot be broken down into simpler forms by hydrolysis. They serve as the building blocks for larger carbohydrates.

Carbohydrates composed of two monosaccharide units linked together. Examples include sucrose (table sugar) and lactose (milk sugar).