General Biology 1 Reviewer - Cell Cycle, Transport, Enzymes, and Photosynthesis

A complete set of vocabulary flashcards covering cell division, transport mechanisms, enzymes, and photosynthesis based on the lecture notes.

Cell Division

The fundamental biological process by which a parent cell divides into two or more new cells.

Mitosis

The apparent division process by which the nucleus divides to produce two new nuclei, resulting in two genetically identical daughter cells.

Cytokinesis

The division of the cytoplasm during cell division.

Metaphase Plate

The plane of alignment halfway between the two spindle poles where centromeres become arranged during metaphase.

Meiosis

A division process that reduces the amount of genetic information and produces haploid gametes or spores with one set of chromosomes.

Haploid

Refers to cells containing $1$ set of chromosomes ($23$ chromosomes in human gametes).

Diploid

Refers to cells containing $2$ sets of chromosomes ($46$ chromosomes in human somatic cells).

Nondisjunction

The failure of homologous chromosomes or sister chromatids to separate properly during cell division.

Synapsis

The specific pairing and twisting of homologous chromosomes around each other during Zygonema of Prophase I.

Bivalent Tetrad

A complex consisting of four chromatids formed during Zygonema in Prophase I.

Crossing-Over

The process of physical exchange of a chromosome's region occurring during Pachynema.

Chiasma

The contact point between two non-sister chromatids that becomes evident during Diplonema.

Passive Transport

A naturally occurring cellular transport process that does not require energy to move particles from high to low concentration.

Diffusion

The movement of particles along a concentration gradient from an area of high concentration to low concentration.

Osmosis

The movement of water through a partially permeable membrane from high to low concentration.

Active Transport

The movement of particles against the concentration gradient from low to high concentration requiring cellular energy.

Isotonic Solution

A solution having the same solute concentration as another solution, resulting in equal water movement in both directions and no net movement.

Hypertonic Solution

A solution containing a higher solute concentration compared to another solution, causing water to move out of the cell and shrink.

Plasmolysis

The shrinking of the protoplasm away from the cell wall when water leaves a plant or bacterial cell.

Hypotonic Solution

A solution containing a lower solute concentration compared to another solution, causing water to enter the cell and swell.

Cytolysis

The bursting of an animal cell due to excessive water entering the cell.

Facilitated Diffusion

A type of passive transport that uses protein channels or carrier proteins to transport substances without using energy.

Bulk Transport

The energy-requiring ($ATP$) transport of macromolecules into and out of the cell.

Exocytosis

A form of bulk transport where materials are transported out of the cell through secretory vesicles merging with the plasma membrane.

Endocytosis

The process by which materials enter the cell via bulk transport.

Phagocytosis

A type of endocytosis, also known as cellular eating, where the plasma membrane surrounds a macromolecule or cell to form a phagosome.

Pinocytosis

A type of endocytosis, also known as cellular drinking, where a cell engulfs droplets of fluid containing dissolved solutes.

Receptor-Mediated Endocytosis

A highly selective endocytosis mechanism that uses receptor proteins found in coated pits of the cell membrane.

Enzymes

Biological molecules, mostly proteins, that speed up chemical reactions by lowering activation energy.

Active Site

A specially shaped area of an enzyme where the substrate binds and catalysis occurs.

Substrate

The specific substance that an enzyme acts upon.

Induced Fit Model

A model describing how an enzyme's active site changes shape to fit the substrate perfectly.

Activation Energy

The minimum energy required for a chemical reaction to occur.

Denaturation

The distortion or alteration of an enzyme's shape due to non-ideal conditions, causing loss of functionality.

Pepsin

A digestive enzyme found in the stomach that breaks down proteins into smaller peptides in an acidic environment.

Photosynthesis

The biological process by which plants make glucose using sunlight, water, and $CO_2$, releasing oxygen as a by-product.

Light-Dependent Reactions

The first stage of photosynthesis occurring in the thylakoid membrane that converts solar energy into $NADPH$ and $ATP$.

Calvin Cycle

The second stage of photosynthesis occurring in the stroma that uses $ATP$, $NADPH$, and $CO_2$ to produce sugar.

Thylakoid

A sheet-like membrane-bound structure in chloroplasts containing Photosystem I ($P700$) and Photosystem II ($P680$).

Photoelectron Transfer

The movement of energized electrons from one molecule to another after absorbing energy from sunlight.

Cyclic Photophosphorylation

A light-dependent pathway where electrons travel in a cycle using Photosystem I and chlorophyll $P700$ to produce $ATP$.

Carbon Fixation

The process of incorporating inorganic $CO_2$ into an organic compound, initiated by the enzyme rubisco.

Ribulose Bisphosphate (RuBP)

A $5$-carbon sugar molecule that attaches to $CO_2$ in the first step of the Calvin cycle.

Glyceraldehyde-3-Phosphate (G3P)

A higher-energy $3$-carbon sugar formed in the Calvin cycle by reducing $3$-PGA using $ATP$ and $NADPH$.