Cell Transport and DNA Replication Lecture Notes

This set of vocabulary flashcards covers the mechanics of active and passive cell transport, surface area to volume ratios in cells, and the step-by-step process of DNA replication and its associated enzymes.

Active transport

A process that requires energy in the form of ATP to move substances against a concentration gradient from low to high concentration.

ATP

The specific form of energy required for active transport processes to occur.

Passive transport

The movement of substances that goes with the concentration gradient, moving from high to low concentration.

Pump

A term used for active transport mechanisms because they require energy and a channel protein to move substances against the concentration gradient.

Exocytosis

The process of moving macromolecules out of the cell using vesicles that fuse with the cell membrane.

Endocytosis

The process of moving macromolecules or food into the cell by engulfing them within the cell membrane to form vesicles.

Diffusion

A type of transport where molecules move straight through the plasma membrane from high to low concentration without requiring energy.

Facilitated transport

The movement of molecules from high to low concentration using a transport protein for assistance, requiring no energy.

Diffusion rate factors

Variables such as temperature, concentration gradient, and pressure, where an increase in these leads to an increase in the rate of diffusion.

Surface Area of a cube

Calculated using the formula $\text{Length} \times \text{Width} \times 6$.

Volume of a cube

Calculated using the formula $\text{Length} \times \text{Width} \times \text{Height}$.

Surface area to volume ratio

A comparison that decreases as a cell's size increases; smaller cells have a higher ratio which allows more food to diffuse into the cell.

DNA monomer

A nucleotide, which consists of a nitrogenous base, a sugar, and a phosphate group.

Purine

A type of nitrogenous base characterized by a double ring structure.

Pyrimidine

A type of nitrogenous base characterized by a single ring structure.

Complementary base pairing

The specific matching of DNA bases where adenine (A) pairs with thymine (T) and cytosine (C) pairs with guanine (G).

DNA Helicase

The enzyme responsible for unzipping and unwinding the DNA double helix by breaking the hydrogen bonds between bases.

DNA Polymerase

The enzyme that helps align free-floating nucleotides with their complementary bases on the DNA template strand.

DNA Ligase

The enzyme responsible for gluing the sugar-phosphate backbone together to join nucleotides.

Semiconservative daughters

The two new DNA molecules produced during replication, each consisting of one original parent strand and one newly made strand.

Template

The original DNA strand used as a guide or stamp to create an exact copy during replication.