General Biology 1: Cell Transport and Cellular Respiration

Vocabulary practice flashcards covering cell transport mechanisms, osmosis, tonicity, active transport, and the stages and yield of cellular respiration.

Cell Transport

The movement of substances into and out of the cell through the cell membrane to obtain nutrients, remove wastes, and maintain homeostasis.

Passive Transport

The movement of substances across the cell membrane from high to low concentration without using cellular energy ($\text{ATP}$).

Simple Diffusion

The movement of molecules directly through the cell membrane from an area of higher concentration to lower concentration without the need for transport proteins or $\text{ATP}$.

Facilitated Diffusion

The movement of substances from high concentration to low concentration with the assistance of membrane transport or channel proteins, requiring no $\text{ATP}$.

Osmosis

The movement of water molecules across a selectively permeable membrane from an area of high water concentration to low water concentration (toward higher solute concentration).

Tonicity

A property describing how an extracellular solution affects the movement of water into or out of a cell.

Isotonic Solution

A solution where the concentration of solutes is approximately equal inside and outside the cell, resulting in no net water movement and allowing the cell to maintain normal size.

Hypotonic Solution

A solution that has a lower solute concentration than the inside of the cell, causing water to move into the cell so animal cells swell and may burst, while plant cells become turgid.

Hypertonic Solution

A solution that has a higher solute concentration than the inside of the cell, causing water to move out of the cell so animal cells shrink and plant cells undergo plasmolysis.

Hypernatremia

An abnormally high concentration of sodium in the blood that causes water to move out of cells, leading to cellular dehydration.

Diabetes Insipidus

A condition characterized by excessive urine production related to problems with antidiuretic hormone ($\text{ADH}$) or the kidney's response to $\text{ADH}$, leading to dehydration and elevated blood sodium levels.

Active Transport

The movement of substances across the cell membrane against their concentration gradient (from low to high concentration) using membrane transport proteins and cellular energy ($\text{ATP}$).

Primary Active Transport

A form of active transport that directly uses energy derived from $\text{ATP}$ to transport substances across the membrane against their gradient.

Sodium-Potassium Pump

A primary active transport protein mechanism that utilizes $\text{ATP}$ to transport $Na^+$ out of the cell and $K^+$ into the cell.

Bulk Transport

The active movement of large materials into or out of cells packaged within membrane-bound vesicles.

Endocytosis

A form of bulk transport in which a cell engulfs external materials into the cell through the formation of vesicles.

Phagocytosis

A type of endocytosis commonly referred to as 'cell eating,' through which a cell ingests large particles, such as white blood cells engulfing bacteria.

Pinocytosis

A type of endocytosis referred to as 'cell drinking,' where the cell takes in fluids and dissolved solutes via vesicles.

Exocytosis

A form of bulk transport that expels materials from the cell into the extracellular space using vesicles, such as in the release of hormones, enzymes, or metabolic wastes.

Cellular Respiration

A series of metabolic reactions that extract usable energy from food molecules (such as glucose) to synthesize $\text{ATP}$, represented by $C_6H_{12}O_6 + 6O_2 \rightarrow 6CO_2 + 6H_2O + \text{ATP}$.

ATP (Adenosine Triphosphate)

The principal energy-carrying molecule utilized by cells for cellular processes, composed of adenine, ribose, and three phosphate groups.

Breathing

The physical process of inhaling air to take in oxygen and exhaling carbon dioxide and water vapor, supplying $O_2$ to blood and tissues.

Aerobic Respiration

A cellular respiration pathway that requires oxygen and yields a high amount of energy, producing approximately $\sim 30\text{--}32\,\text{ATP}$ per glucose molecule across cytoplasmic and mitochondrial stages.

Fermentation

An anaerobic process occurring entirely in the cytoplasm when oxygen is absent or insufficient, regenerating electron carriers to allow glycolysis to continue with lower $\text{ATP}$ production.

Glycolysis

The initial stage of cellular respiration occurring in the cytoplasm, breaking down one glucose molecule into $2$ pyruvate molecules, yielding a net of $2\,\text{ATP}$ and $2\,\text{NADH}$.

Pyruvate Oxidation

The stage occurring upon pyruvate entering the mitochondrion in the presence of oxygen, converting pyruvate to $2\,\text{acetyl-CoA}$ while generating $2\,\text{NADH}$ and $CO_2$, yielding $0\,\text{ATP}$.

Krebs Cycle

The metabolic cycle located in the mitochondrial matrix that processes acetyl-$\text{CoA}$ to produce $2\,\text{ATP}$, $6\,\text{NADH}$, $2\,\text{FADH}_2$, and $CO_2$.

Electron Transport Chain (ETC)

A series of protein complexes located in the inner mitochondrial membrane that uses high-energy electrons from $\text{NADH}$ and $\text{FADH}_2$ to generate a proton gradient.

Chemiosmosis

The mechanism wherein hydrogen ions ($H^+$) move down their electrochemical gradient through $\text{ATP}$ synthase, providing the energy to produce $\text{ATP}$.

Final Electron Acceptor

The role played by oxygen ($O_2$) at the end of the electron transport chain, binding with electrons and hydrogen ions ($H^+$) to form water ($H_2O$).