Chapter 5: The Working Cells Flashcards
True or false: The fact that all cells have a plasma membrane supports the evolutionary linkage of all life?
True
Which best describe the structure of a cell membrane?
Proteins embedded in a bilayer of phospholipids
The sodium concentration in a cell in 10 times less than the concentration in the surrounding fluid? How can the cell move sodium out of the cell?
By Active transport
The synthesis of ATP from ADP and P?
Stores energy in a form that can drive cellular work
What are the main types of cellular work? How does ATP provide the energy for this work?
The work of a cell falls into three main categories: chemical, transport, mechanical. ATP provides E for cellular work; During the hydrolysis of ATP, a phosphate group is often transferred to a substrate (chemical) or to a protein (transport, mechanical)
Diffusion of water across a selectively permeable membrane.
Osmosis
Movement across a cell membrane that requires no work from the cell.
Diffusion
Movement of a substance from high to low concentration.
Passive transport
When there exists a difference in the amount of substance across a distance.
Concentration gradient
Compare and contrast endocytosis and exocytosis.
Endocytosis: into the cell; molecules/ particles are packaged into vesicles
Exocytosis: exit out of the cell; secretory vesicles secretes substances outside the cell
Both are moving large molecules into and out of cells
In contrast to passive transport, active transport pumps a substance ___ its gradient.
UP
The sum of all chemical reactions in an organism.
Metabolism
A series of reactions that either build or break down a molecule.
Metabolic pathway
A reaction that gives off energy.
Exergonic reaction
A reaction that requires an input of energy.
Endergonic reaction
