Chapter 5 Membrane Transport and Cell Signaling

Key Concepts

Cellular membranes are fluid mosaics of lipids and proteins
Membrane structure results in selective permeability
Passive transport is diffusion of a substance across a membrane with no energy investment
Active transport uses energy to move solutes against their gradients
Bulk transport across the plasma membrane occurs by exocytosis and endocytosis
The plasma membrane plays a key role in most cell signaling

Detailed Learning objectives

5.1 Describe the structure of the fluid mosaic model, including the kinds of macromolecules that make up a membrane, their ability to move in the membrane, and the characteristics of the different molecules in terms of bonding and hydrophobicity

5.2 Describe how bacteria, plants, and animals can change the composition of their membranes to account for differences in temperature in the environment.

5.3 Understand that while membrane proteins have many functions, their ability to transport specific substances, either as carrier or channel proteins, make the membrane a selectively permeable layer

5.4 Describe how passive transport utilizes the movement of a substance along a concentration gradient

5.5 Define osmosis

5.6 Relate the concentration of solutes in a solution outside a cell to the concentration of solutes inside the cell using the concepts of isotonic, hypertonic and hypotonic

5.7 Compare and contrast (1) facilitated diffusion using channel proteins with (1) active transport, paying particular attention to ion pumps such as the Na/K pump

5.8 Compare and contrast phagocytosis, pinocytosis, and receptor-mediated endocytosis

LECTURE SLIDES

Chapter 5 Lecture Slides

activities

Gummy Bear Case Study

assignments

Homework - These are interactive assignments, videos, tutorials, etc. designed to reinforce and allow you to apply concepts from the chapter. These assignments are a form of studying the material. Late submissions are penalized 10% each day, with no more than 50% late penalty. This setting is automatically applied to all assignments.

Adaptive Follow-up - After completing the homework assignment, a follow up assignment to be completed in 3 days will open to focus on areas where you need more development. If you score 90% or higher on the initial homework assignment, you do not have to complete the follow-up and will earn the points automatically.

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Dynamic Study Modules - these remain available for the duration of the semester for you to use.
Study Area - includes videos and animations, vocabulary study tools, practice quizzes, and more.

Terminology

Key Terminology and Vocabulary - While the "jargon" or terminology in scientific fields can initially be intimidating, the use of specific language allows for more effective communication and clarity. Learn these words and be able to use them properly in the context of biology. It takes time and practice to make words "your own" so don't be afraid to try to use them!

Selective permeability
amphipathic
fluid mosaic model (be able to explain what this is/means)
integral proteins
peripheral proteins
glycolipids
glycoproteins
transport proteins
aquaporins
diffusion
concentration gradient
passive transport
osmosis
tonicity
- isotonic/hypertonic/hypotonic
osmoregulation
plasmolysis
facilitated diffusion
ion channels
gated channels
active transport
sodium potassium pump
membrane potential
electrochemical gradient
electrogenic pump
proton pump
cotransport
endocytosis
exocytosis
hormones
signal transduction
protein kinase
phosphorylation cascade
cyclic AMP (cAMP)