FinalExamReview_ICB-KEY

What is the role of the dependent variable (DV) in an experiment?

The dependent variable is the variable that is measured or observed in the experiment and responds to changes in the independent variable.

What does the independent variable (IV) represent in an experiment?

The independent variable is the variable that is manipulated or controlled by the experimenter and is the presumed cause in a cause-and-effect relationship.

What is the purpose of control groups in an experiment?

Control groups are used as a baseline for comparison to the experimental groups and ensure that any changes in the dependent variable are due to the independent variable and not other factors.

What distinguishes experimental groups in an experiment?

Experimental groups are those that are exposed to the independent variable being tested.

What was the key observation in Meselson and Stahl's experiment after the second round of DNA replication?

Equal amounts of light, hybrid, and heavy DNA were observed.

What is MHC I and its function?

MHC I (Major Histocompatibility Complex Class I) is a protein complex found on the surface of most nucleated cells that presents intracellular peptides to the immune system, enabling detection of infected or abnormal cells.

What are the factors that can result in immune rejection regarding MHC I?

A mismatch in MHC I molecules or the absence/downregulation of MHC I can lead to immune rejection.

What was the significance of Griffith's experiment with Streptococcus pneumoniae?

Griffith's experiment demonstrated that non-virulent bacteria could be transformed into virulent bacteria by taking up genetic material from heat-killed virulent bacteria.

What is the central dogma of molecular biology?

The central dogma describes the flow of genetic information from DNA to RNA to protein.

How does the Bohr effect influence hemoglobin's oxygen-binding capacity?

The Bohr effect describes how an increase in CO₂ or a decrease in pH causes hemoglobin to release oxygen more readily.

What is quorum sensing in bacteria?

Quorum sensing is a bacterial communication process that enables bacteria to coordinate their behavior based on their population density through the production and detection of signaling molecules.

What are the stages of the cell cycle?

The stages of the cell cycle include G1, S (DNA duplication), G2 (prep for division), and M (mitosis), followed by cytokinesis.

What is the significance of crossing over in meiosis?

Crossing over increases genetic diversity by exchanging segments of DNA between homologous chromosomes.

What is the process of osmosis?

Osmosis is the passive movement of water molecules across a selectively permeable membrane from an area of low solute concentration to an area of high solute concentration.

What happens to cells in a hypertonic solution?

In a hypertonic solution, water moves out of the cell, causing animal cells to crenate (shrink) and plant cells to plasmolyze (pull away from the cell wall).

What is the primary function of ATP in cellular metabolism?

ATP serves as an energy shuttle in the cell, coupling exergonic and endergonic reactions.

How do plants respond to drought stress?

Plants respond to drought stress by closing stomata to minimize water loss and upregulating genes involved in drought resistance.

What is the function of the sodium-potassium pump?

The sodium-potassium pump actively transports 3 Na⁺ ions out of the cell and 2 K⁺ ions into the cell, which is essential for maintaining resting membrane potential.

What is denaturation of proteins?

Denaturation refers to the loss of a protein's three-dimensional structure, leading to a loss of function and potentially threatening the organism's survival.