IB Bio HL1 Final Exam 2024

Front

During the tertiary folding stage, non-polar amino acids will orient themselves on the ____________ of the molecule.

Back

interior

Front

Endocytosis is defined as ____________.

Back

the movement of large molecules from the outside of the cell to the inside of the cell using membrane vesicles.

Front

During diffusion, substances move ____________.

Back

down a concentration gradient.

Front

What allows small insects to walk across the surface of calm water?

Back

The insects are light enough so that they do not break the hydrogen bonds holding the water molecules together.

Front

Define endocytosis.

Back

The process by which cells internalize substances from their external environment using vesicles.

Front

What is the role of non-polar amino acids in protein structure?

Back

They contribute to the hydrophobic core of proteins, stabilizing their three-dimensional structure.

Front

Explain the concept of a concentration gradient.

Back

A concentration gradient occurs when there is a difference in the concentration of a substance across a space.

Front

What is the difference between passive and active transport?

Back

Passive transport does not require energy and moves substances down their concentration gradient, while active transport requires energy to move substances against their concentration gradient.

Front

What is the significance of hydrogen bonds in water?

Back

Hydrogen bonds give water its unique properties, such as high surface tension and the ability to support small insects.

Front

Describe the process of diffusion.

Back

Diffusion is the movement of molecules from an area of higher concentration to an area of lower concentration until equilibrium is reached.