Module 3 Test

What cellular process is represented in the accompanying figure?

Exocytosis

Mutations to ABC transporter genes contribute to cystic fibrosis.

True

During signal transduction of a G protein, the first messenger binds to the receptor, and the G protein is activated. What happens next?

Activation of adenylyl cyclase

Which proteins are located on the inner or outer surface of the plasma membrane, usually bound to exposed regions of integral proteins by noncovalent interactions?

Peripheral membrane proteins

Which is a part of a signal transduction pathway that enables vision in dim light in vertebrates?

Rhodopsin

magnification

The ratio of the size of the image seen with the microscope to the actual size of the object is called:

Which statement about receptors is false?

They are also called ligands.

Most intracellular receptors are what type of protein?

Transcription factors

microtubule

You isolate a cellular structure and determine that it is composed of α-tubulin and β-tubulin. Based on this evidence, you correctly identify this structure as a(n):

Which cellular structure is correctly matched to the role it plays within the cell?

centrosome−cell division

During enzyme-linked reception, signal molecules bind to two tyrosine kinase receptors. The receptor proteins move closer together in the plasma membrane and pair, forming a(n) ____.

dimer

The outer membrane of the nuclear envelope is continuous with the membrane of the ____ and is usually covered with attached ribosomes.

endoplasmic reticulum

Fluid that has a higher osmotic pressure than a cell is called ___________.

hypertonic

When the net movement of water in and out a cell is zero, that solution is said to be

isotonic

Which of the following organelles plays an important role in apoptosis, or programmed cell death?

mitochondria

Which two organelles are responsible for converting energy into forms that can be used by cells?

mitochondria and chloroplasts

The process by which the plasma membrane separates from the cell wall is called ______.

plasmolysis

Ion channels are found in the plasma membranes of neurons and muscle cells.

True

Microfilaments are linked with one another and with other proteins by linker proteins.

True

What is a characteristic found in both prokaryotic and eukaryotic cells?

plasma membrane

Name the part of the cell outside the nucleus.

Cytoplasm

G protein-linked receptors are transmembrane proteins with a binding site for a signaling molecule outside the cell and a neuron component inside the cell.

False

Groups of eight connexin molecules cluster to form a cylinder that spans the plasma membrane.

False

A patient who has had a severe hemorrhage accidentally receives a large transfusion of distilled water directly into a major blood vessel. What effect will this have on the patient?

It will have serious, perhaps fatal consequences because the red blood cells could swell and burst.

What type of chemical compound diffuses across synapses?

Neurotransmitters

The gas ethylene is a plant hormone that regulates a variety of processes, including seed germination and ripening of fruit.

True

What process halts the net movement of water from a hypotonic solution into a plant's cells and often provides the structural support to many plants?

Turgor pressure

Peripheral proteins are linked to either surface of the plasma membrane by

bonding to integral proteins through noncovalent interactions.

What is the microtubule arrangement of a flagellum or cilium?

9 + 2 arrangement

Adenylyl cyclase catalyzes the reaction in which

ATP is converted to cAMP.