Chemistry of Life and Cellular Transport

Vocabulary flashcards covering Topic 1.2 Chemistry of Life and Cell Structure/Transport Mechanisms based on lecture notes.

Matter

Anything that has mass and occupies space.

Element

A pure substance that cannot be broken down further (e.g., Oxygen).

Compound

A chemical combination of two or more elements (e.g., Water).

Proton

A subatomic particle that carries a positive charge ($+$).

Electron

A subatomic particle that carries a negative charge ($-$).

Neutron

A subatomic particle that is neutral.

Atomic Number

The number of protons in the nucleus of an atom.

Atomic Weight

The total number of protons plus the number of neutrons in an atom.

Ionic Bond

A chemical bond formed when one atom transfers an electron from its outer shell to another atom.

Potential Energy

Energy waiting to get used, stored in the bonds of molecules, and released through chemical reactions.

Organic Compounds

Compounds that contain carbon.

Inorganic Compounds

Compounds that do not contain carbon.

Water (Solvent)

A compound that ionizes chemical compounds, lubricates structures, and acts as a temperature mediator in the body.

Acid

A substance that releases $H^+$ ions when dissolved in water and acts as a proton donor; a stronger acid contains more $H^+$ ions.

Base

A substance containing $OH^-$ ions that acts as a proton acceptor.

pH Scale

A scale measuring acidity and alkalinity where a value less than 7 ($< 7$) is acidic, 7 is neutral, and a value greater than 7 ($> 7$) is basic.

Normal Human pH

The physiological pH range of the human body, which is $7.35\text{--}7.45$.

Carbohydrates

The body's main energy source consisting of carbon, hydrogen, and oxygen (C, H, O), which includes sugars and starches.

Lipids

Organic compounds insoluble in water that serve as an energy reservoir and consist of C, H, and O.

Saturated Fats

Fats considered 'bad fats' that have straight hydrocarbon tails filled with hydrogen (e.g., butter).

Unsaturated Fats

Fats considered 'good fats' that have kinky hydrocarbon tails (e.g., olive oil).

Proteins

Abundant compounds consisting of amino acids that make up structural and functional components in the human body.

Nonessential Amino Acids

The 11 amino acids that the human body can synthesize by itself.

Essential Amino Acids

The 9 amino acids that cannot be produced by the body and must be obtained through diet.

Nucleic Acids

Molecules consisting of nucleotides made of a 5-carbon sugar, a phosphate group, and a nitrogenous base, with the two main types being DNA and RNA.

ATP (Adenosine Triphosphate)

A nucleic acid derivative that stores energy for cellular processes.

Human Cell Dimensions

Most cells are microscopic, with typical human cell sizes measuring $10\text{--}15$\,micrometers ($\mu\text{m}$).

Plasma Membrane

A thin membrane forming the outer boundary of a cell that is selectively permeable and does not let everything through.

Nucleus

The control center of the cell that contains genetic information.

Organelles

Structures found in the cytoplasm that each carry out a specific task or function for the cell.

Golgi Apparatus

An organelle that acts as the cell's 'post office'.

Centrioles

Organelles that play a key role in cell division.

Lysosomes

Organelles containing various enzymes that help break down proteins the cell does not need.

Mitochondria

The powerhouse of the cell that supplies cellular energy via ATP production.

Cytoskeleton

An internal framework of the cell composed of structural elements such as cilia, microvilli, and flagella.

Cilia

Hair-like structures that exhibit a wave-like motion to move materials along the cell surface.

Microvilli

Cell membrane projections that help increase surface area.

Flagella

Cellular structure that uses a whip motion to propel sperm cells.

Passive Transport

Movement of substances across cell membranes without any energy consumption (e.g., diffusion, osmosis, filtration, facilitated diffusion).

Active Transport

Movement of substances across cell membranes requiring energy input, including transport by pumps and vesicles.

Diffusion

The movement of particles from an area of high concentration to an area of low concentration until equilibrium is reached.

Osmosis

The movement of water across a semipermeable membrane until equal concentration is reached on each side.

Tonicity

The concentration of solute in fluids to which cells are exposed.

Isotonic

A solution having the same solute concentration as the inside of the cell, resulting in no net movement of water (e.g., IV solutions).

Hypertonic

A solution with a higher concentration of solutes than that inside the cell.

Hypotonic

A solution with a lower concentration of solutes than that inside the cell.

Filtration

The movement of water and dissolved solutes across a membrane due to pressure differences.