The Chemistry of the Cell

A set of flashcards covering key concepts from the lecture on 'The Chemistry of the Cell', including atoms, molecules, pH, chemical bonds, and functional groups.

What are the three subatomic particles that make up an atom?

Protons, neutrons, and electrons.

What does the periodic table of elements provide?

Information on atomic symbols, atomic numbers, and atomic masses.

What is an ion?

An atom with different numbers of protons and electrons.

What is an example of a stable atom?

Helium (He) is an example of a stable atom.

How do atoms achieve stability?

By filling their outermost electron shell to capacity.

What defines a molecule?

A substance formed by the chemical combination of two or more elements in definite proportion.

What type of bond involves the transfer of electrons?

Ionic bond.

What are the two main types of covalent bonds?

Polar covalent and nonpolar covalent bonds.

What does a pH measure?

The concentration of hydrogen ions (H+) in a solution.

What is the result of an acid reacting with a base?

The formation of salt and water.

What is a buffer?

A substance that stabilizes pH by releasing or absorbing H+ as needed.

What is the bicarbonate buffer system important for?

Maintaining blood pH within the normal range.

What is represented by a molecular formula?

It shows how many atoms of each element are present in a molecule.

What do functional groups determine in organic molecules?

They determine the biochemical role of the molecules.

What is unique about the molecular structure of hydrocarbons?

They are primarily composed of carbon and hydrogen.

What is a phospholipid bilayer?

The fundamental structure of the cell membrane, consisting of two layers of phospholipid molecules with hydrophilic heads facing outwards and hydrophobic tails facing inwards.

What is a hypertonic solution?

A solution with a higher concentration of solutes outside the cell than inside, causing water to leave the cell.

What is a hypotonic solution?

A solution with a lower concentration of solutes outside the cell than inside, causing water to enter the cell.

What is an isotonic solution?

A solution with the same solute concentration inside and outside the cell, resulting in no net water movement.

What is simple diffusion?

The passive movement of substances directly across a membrane from an area of high concentration to an area of low concentration.

What is facilitated diffusion?

The passive movement of substances across a membrane with the help of transport proteins, from an area of high concentration to an area of low concentration.

What is osmosis?

The passive movement of water across a semipermeable membrane from an area of high water concentration (low solute) to an area of low water concentration (high solute).

What is the importance of K+ leak channels to the cell in its resting state?

They maintain the cell's negative resting membrane potential by allowing potassium ions (K+) to slowly diffuse out of the cell, down their concentration gradient.

What is the function of the nucleus?

It contains the cell's genetic material (DNA) and controls cell growth, metabolism, and reproduction.

What is the function of the nucleolus?

It is involved in the synthesis of ribosomal RNA (rRNA) and the assembly of ribosomes.

What are chromatin strands?

A complex of DNA and proteins (histones) that forms chromosomes within the nucleus of eukaryotic cells, responsible for packaging DNA into a compact shape.

What is the function of ribosomes?

They are the sites of protein synthesis, translating messenger RNA (mRNA) into polypeptide chains.

What is the function of the rough endoplasmic reticulum (RER)?

Involved in the synthesis and modification of proteins destined for secretion or insertion into membranes, studded with ribosomes.

What is the function of the smooth endoplasmic reticulum (SER)?

Involved in lipid synthesis, detoxification of drugs and poisons, and storage of calcium ions.

Are phospholipids amphipathic?

Yes, phospholipids are amphipathic because they have both hydrophilic (water-loving) heads and hydrophobic (water-fearing) tails.

What is the function of the Golgi apparatus?

Modifies, sorts, and packages proteins and lipids synthesized in the ER for secretion or delivery to other organelles.

What is the function of lysosomes?

They are the cell's 'recycling centers,' containing enzymes that break down waste materials, cellular debris, and foreign invaders.

What is the function of mitochondria?

They are the 'powerhouses' of the cell, generating most of the cell's supply of adenosine triphosphate (ATP) through cellular respiration.

What is the function of the cytoskeleton?

A network of protein filaments and tubules in the cytoplasm of many living cells, giving them shape and coherence.

What is the function of a vesicle?

A small fluid-filled sac within a cell, involved in transporting materials within the cytoplasm or to the outside of the cell.

What is the difference between an anion and a cation?

An anion is a negatively charged ion (gains electrons), while a cation is a positively charged ion (loses electrons).

What is the purpose of the K+/Na+ pump?

It actively transports three sodium ions (Na+) out of the cell and two potassium ions (K+) into the cell, maintaining membrane potential and electrochemical gradients essential for nerve impulses and cell volume.