ch. 3 Cell Membrane Transport and Nucleus Structure

These flashcards cover key vocabulary terms and concepts related to cell membrane transport mechanisms and the structure of the nucleus, focusing on definitions and important processes.

Hydrophobic

Refers to the part of the phospholipid bilayer that repels water and prevents polar substances from passing through.

Active Transport

The process of moving molecules against their concentration gradient, which requires energy.

Passive Transport

The movement of substances across a cell membrane without the need for energy, usually down a concentration gradient.

Osmosis

The diffusion of water across a selectively permeable membrane from a hypotonic solution to a hypertonic solution.

Hypertonic Solution

A solution with a higher concentration of solutes compared to another solution.

Hypotonic Solution

A solution with a lower concentration of solutes compared to another solution.

Sodium-Potassium Pump

A type of active transport that moves sodium out of the cell and potassium into the cell against their concentration gradients.

Vesicular Transport

Transport of large molecules across a membrane via vesicles, involving processes like endocytosis and exocytosis.

Resting Membrane Potential

The electrical voltage difference across a cell membrane when a cell is at rest.

Chromatin

The less condensed form of DNA that is used during DNA replication and protein synthesis.

Chromosome

A condensed form of DNA that is easy to separate during cell division.

Mitosis

The process in which a cell's nucleus divides in preparation for cell division, including stages such as prophase, metaphase, anaphase, and telophase.

Cytokinesis

The physical process of cell division, which follows mitosis, resulting in two daughter cells.

DNA Polymerase

An enzyme that synthesizes new strands of DNA by adding nucleotides complementary to the template strand.

Histones

Proteins that help package DNA into a compact, dense structure, allowing for proper DNA organization and regulation.