Biology 12
Biology 12 Cell Biology - Transport across Cell Membrane
Text Reference: Chapter 5 pp 72-85
Vocabulary:
active transport, carbohydrates, carrier protein, cell membrane, channel protein, cholesterol, concentration gradient, diffusion, endocytosis, exocytosis, facilitated transport, fluid-mosaic membrane model, glycolipid, glycoprotein, hydrophilic, hydrophobic, hypertonic, hypotonic, isotonic, osmosis, passive transport processes, phagocytosis, phospholipid, phospholipid bilayer, pinocytosis, pressure gradient, protein, selectively permeable, surface area-to-volume ratio, tonicity
It is expected that students will:
B9 Analyse the structure and function of the cell membrane
B9.1 apply knowledge of organic molecules – including phospholipids, proteins, glycoproteins, glycolipids, carbohydrates, and cholesterol – to explain the structure and function of the fluid-mosaic membrane model
B9.2 identify the hydrophobic and hydrophilic regions of the phospholipid bilayer
B9.3 explain why the cell membrane is described as “selectively permeable”
B9.4 describe passive transport processes including diffusion, osmosis, and facilitated transport
B9.5 explain factors that affect the rate of diffusion across a cell membrane (e.g., temperature, size of molecule, charge of molecule, concentration gradient, pressure gradient)
B9.6 predict the effects of hypertonic, isotonic, and hypotonic environments on osmosis in animal cells
B9.7 describe active transport processes including active transport, endocytosis (phagocytosis and pinocytosis), and exocytosis
B9.8 compare specific transport processes – including diffusion, osmosis, facilitated transport, active transport, endocytosis, and exocytosis – in terms of
– concentration gradient
– use of channel or carrier protein
– use of energy
– types/sizes of molecules transported
B9.9 devise an experiment using the scientific method (e.g., to investigate the tonicity of cells)
B10 Explain why cells divide when they reach a particular surface area-to-volume ratio
B10.1 differentiate between cells that have a high or low surface area-to-volume ratio
B10.2 demonstrate an understanding of the significance of surface area-to-volume ratio in cell size
The cell membrane is often described as a ‘fluid mosaic’. What could that mean? The next 3 pages will help you to understand this concept. (pg. 73-75)
Activity: Membrane Structure (5.1)
Here is what happens when phospholipids are put in water:
Here are two great websites to visualize the cell membrane:
1. Review why the phospholipid molecule is an ideal molecule to make up cell membranes.
____________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
What characteristic of the phospholipid bilayer could be described as fluid?
___________________________________________________________________________________________________________________________________________________________________________________________________
Here is a more detaileld diagram to illustrate what your cell membranes might look like:
What do we mean when we describe the cell membrane as a ‘mosaic’?
________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
What is the function of cholesterol in the animal cell membrane?
________________________________________________________________________________________________________________________________________________
2. What are some of the functions of membrane proteins?
a) __________________________________________________________________ __________________________________________________________________
b) ____________________________________________________________________________________________________________________________________
c) __________________________________________________________________
_________________________________________________________________
d) __________________________________________________________________
__________________________________________________________________
e) _________________________________________________________________
__________________________________________________________________
f) __________________________________________________________________
__________________________________________________________________
3. How do Substances Cross The Cell Membrane? (pg. 75)
Crash Course – Transport:
What do we mean when we say that molecules diffuse ‘down their concentration gradient’?
________________________________________________________________________________________________________________________________________________________________________________________________________________________
Website activity: Activity: Diffusion (5.3)
Activity: Selective Permeability of Membranes (5.1)
Why are cell membranes described as selectively permeable?
________________________________________________________________________________________________________________________________________________
Activity: Osmosis and Water Balance in Cells (5.5)
Activity: Facilitated Diffusion (5.6)
3. Passive Transport across the cell membrane
One solute:
BLAST Animation: Diffusion (5.3)
What do we mean when we say that some molecules or ions cross the cell membrane by passive transport?
________________________________________________________________________________________________________________________________________________________________________________________________________________________
More than one solute:
BLAST Animation: Passive Diffusion Across a Membrane (5.3)
What is simple diffusion across the cell membrane? _____________________________
________________________________________________________________________________________________________________________________________________
Give some examples of molecules that are able to move by simple diffusion across the plasma membrane.
___________________________________________________________________________________________________
What determines whether or not a molecule/ion can travel across the phospholipid bilayer by simple diffusion?
___________________________________________________________________________________________________
Does simple diffusion require an input of energy (ATP) by the cell? ________________
Does simple diffusion require a membrane protein? _____________________________
Explain factors that affect the rate of diffusion across a cell membrane
Try to find 5 factors to explain.
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
________________________________________________________________________
How is facilitated transport similar to simple diffusion?
________________________________________________________________________________________________________________________________________________________________________________________
How does facilitated transport differ from simple diffusion?
______________________________________________________________________________________________________________________________________________________________________________________________
Give some examples of biologically important molecules that must cross the membrane by facilitated transport?
________________________________________________________________________________________________________________________________________________________________________________________________________________________
What is osmosis? (pg. 76) _________________________________________________________________________________________________________________________________
______________________________________________________________________________________
What happens to plant and animal cells when they are placed in hypertonic, hypotonic and isotonic solutions? (pg. 76-77)
________________________________________________________________________________________________________________________________________________________________________________________________________________________
________________________________________________________________________________________________________________________________________________________________________________________________________________________
Some molecules move across the cell membrane by active processes. What does this mean? (pg. 78) __________________________________________________________
_______________________________________________________________________
Activity: Active Transport (5.8)
List the three types of transport that are considered to be active methods:
________________________________________________________________________
What are the distinguishing features of active transport?
________________________________________________________________________________________________________________________________________________
[pic]
Give some examples of molecules or ions that cross the membrane by active transport:
________________________________________________________________________________________________________________________________________________________________________________________________________________________
BLAST Animation: Active Transport (5.8)
What is exocytosis? (pg. 79)_________________________________________________
________________________________________________________________________________________________________________________________________________
Activity: Exocytosis and Endocytosis (5.9)
BLAST Animation: Endocytosis and Exocytosis (5.9)
Give some examples of molecules that must leave the cell by exocytosis:
__________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
Is exocytosis an active or passive process? ______________________ Why? ________
________________________________________________________________________
What is endocytosis? _____________________________________________________
________________________________________________________________________________________________________________________________________________
Which cells in your body do a lot of endocytosis? __________________________________________________________
What must happen after the vesicle is formed? ____________________________________________________________________________________________________________________________________________________________________________
Is endocytosis an active or passive process? _____________________ Why? ________
________________________________________________________________________
There are two types of endocytosis – phagocytosis and pinocytosis. What is the difference between phagocytosis and pinocytosis? (pg. 79)
________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________________
[pic]BioFlix: Membrane Transport chapter 5
Complete this concept map to help with your understanding of how substances cross the cell membrane:
Demonstrate an understanding of the relationship and significance of surface area to volume, with reference to cell size
cool site
What is the average size range for cells? ________________________________
WHAT LIMITS CELL SIZE?
In order to grow, cells need to take in _____________________________ and get rid of __________________________________.
Which part of the cell controls the entrance and exit of these materials? _________________________________________
What determines how much material is needed by the cell, or how much waste is produced by the cell? ______________________________
Study the large cell on the left below. How does its volume compare to the total volume of the 27 small cells on the right? _______________________________
How does its surface area compare? ___________________________________
What which has a better RATIO of surface area to volume, the one large cell, or the 27 small cells? _________________________________________
Explain why cells stop growing and divide once they reach a certain size.
___________________________________________________________________________________________________________________________
_________________________________________
-----------------------
[pic]
................
................
In order to avoid copyright disputes, this page is only a partial summary.
To fulfill the demand for quickly locating and searching documents.
It is intelligent file search solution for home and business.
Related searches
- dow close on 12 31 2018
- dod 7000.14 r vol 12 ch 7
- stock market last 12 months
- 12 month interest free loan
- top 12 dividend paying stocks
- 12 interest rate investments
- 12 interest rate savings account
- nelson grade 12 biology textbook
- numbers 12 12 12 and meaning 333
- xtr 12 semi auto 12 gauge
- mark 12 1 12 commentary
- fentanyl 12 vs 12 5