Ask a Question
Home
Take a Tour
Study Tips
Help Pages
Contact Us
Gallery
Recently Added
Videos
Search
Blogs
Dictionary
Add New Word
Random Term
Recent Changes
Resource Library
Share Your Resources
Recently Added
Search
Forum
Ask a Question
Log In
Log In
Forgot your password?
Sign Up
for all your
science
needs
Forum
Search
Advanced Search
Image Gallery
Resource Library
Topics
Unresolved Questions
Discussions
Trending
Recent Posts
Chat
Subjects
Join over
250,000
students, educators, and subject enthusiasts in our free online study community
More
Q & A Board
Entire Website
Gallery
Resource Library
Dictionary
Blogs
Search through 1.7M homework questions
Unresolved Questions
•
Discussions
•
Recent
Top Posters
Since Sunday
34
28
15
13
13
12
11
10
10
10
9
9
Post a New Question
Current Questions
Home
Q & A Board
Laboratory Help
Introductory Courses
Print
New Topic
Why didn't the ions move through channel proteins or transport proteins?
Yeast cells sem
Yeast cells sem
wrote...
4 months ago
4 months ago
Why didn't the ions move through channel proteins or transport proteins?
Hello! I recently made an experiment at school to test the semi permeability of the cell membrane of yeast cells. I did as following:
1.Sodium bicarbonate solution was put into a conical flask
2. Drops of the indicator neutral red was added and the colour turned yellow as it was basic.
3. A mixture of yeastcells and sodium bicarbonate was added to the conical flask and colour turned pink.
4. An amount of Sodium hydroxide solution was added then but no colour change was observed.
Well I know that the colour changed to pink at first because the neutral red diffused into the yeast cells and changed color to pink due to the acidity of yeast cells.
I also know the sodium hydroxide is ionised in this condition and is thereby present as hydroxide ions and sodium ions. And these being polar(charged) and ions can't diffuse into the yeast cells and change the pH of it to produce a colour change. But why didn't they get into the cells with the help of channel or transport proteins that are made to transport ions? Why did they stay on the outside? I am also mostly curious about the hydroxide ions as it is they that can make a solution basic and change the colour.
Anyone could help!!!
Thank you so much!!!
Read 341 times
12
Replies
Related Topics
Solved
why is facilitated diffusion using channel proteins considered passive transport?
Solved
. What is the role of transport and channel proteins within the fluid mosaic of a plasma membrane?
Solved
Channel proteins allow ions that would not normally pass through the cell membra
Solved
The specialized membrane proteins that actively transport sodium and potassium ions across the ...
Solved
Within the fluid mosaic of a plasma membrane, what is the role of transport and channel proteins?
Proteins use the process of active transport to move substances into or out of the cell by:
Solved
Proteases are : (Multiple Choice)
Solved
Most lipids need to be attached to transport proteins to move through blood.
Load More
Replies
bolbol
wrote...
#1
Staff Member
4 months ago
Assuming that the yeast cells are alive, transport ions require ATP, so whether or not sufficient energy was being produced is something you need to consider in your results.
Wait for other replies, I'm sure others can chime in
Report
Thank you for using Biology-Forums.
bio_man
wrote...
#2
Educator
4 months ago
Very interesting, so after adding the base (NaOH), you were expecting the pink solution to revert back to yellow. I'm assuming you think this because it tips the balance back to basic. I'm curious, is the neutral red indicator supposed to change color after a reaction has occurred? Most indicators have a point of no return, so maybe the ions are being transported, but you're not seeing that happen due to the indicators limitations.
Just a thought
Report
The best way to say thank you is with a positive review:
https://trustpilot.com/review/biology-forums.com
Your support goes a long way!
▶
Make a note request here
Dima Harba
wrote...
#3
4 months ago
Quote from: bolbol (4 months ago)
Assuming that the yeast cells are alive, transport ions require ATP, so whether or not sufficient energy was being produced is something you need to consider in your results. Wait for other replies, I'm sure others can chime in
Thanks for your reply. That is exactly my question acually.
Post Merge: 4 months ago
Quote from: bio_man (4 months ago)
Very interesting, so after adding the base (NaOH), you were expecting the pink solution to revert back to yellow. I'm assuming you think this because it tips the balance back to basic. I'm curious, is the neutral red indicator supposed to change color after a reaction has occurred? Most indicators have a point of no return, so maybe the ions are being transported, but you're not seeing that happen due to the indicators limitations. Just a thought
I tried it with ammonia and it changed colours so the indicator doesn't have limitations.
Report
bolbol
wrote...
#4
Staff Member
4 months ago
Thanks for clearing that up.
Now, if transport ions embedded in the membrane require ATP (therefore,
active transport
), then the yeast cells need to be alive for them to generate ATP. If they don't need ATP, but rely on simple diffusion (
passive transport
), then the ion concentration
outside
must be at equilibrium with what it is
inside
the cell, accounting for your observations.
Report
Thank you for using Biology-Forums.
bio_man
wrote...
#5
Educator
4 months ago
Quote from: Dima Harba (4 months ago)
I tried it with ammonia and it changed colours so the indicator doesn't have limitations.
The fact that NH3 caused it to become yellow means there's evidence of transport into the cell. What you could do to determine if the yellow yeast cells are still alive by conducting a fermentation experiment or by observing the yeast cells bud after adding a glucose solution to the yellow yeast cells.
When you applied sodium bicarbonate, did you apply any heating to the solution containing the cells? The only way the cells can become permeable to sodium bicarbonate is through heating, allowing the sodium bicarbonate to interact with the neutral red.
Maybe your observations are correct. NaOH should keep the solution pink, creating no change.
Report
The best way to say thank you is with a positive review:
https://trustpilot.com/review/biology-forums.com
Your support goes a long way!
▶
Make a note request here
Dima Harba
wrote...
#6
4 months ago
Edited:
4 months ago, Dima Harba
Quote from: bolbol (4 months ago)
Thanks for clearing that up. Now, if transport ions embedded in the membrane require ATP (therefore,
active transport
), then the yeast cells need to be alive for them to generate ATP. If they don't need ATP, but rely on simple diffusion (
passive transport
), then the ion concentration
outside
must be at equilibrium with what it is
inside
the cell, accounting for your observations.
.. Aha.. Well, I'm guessing they aren't alive due to the basic pH of sodium bicarbonate solution so they won't be able to use ATP. But what about channel proteins? They don't require energy and they use facilitated diffusion? Is there something specific about hydroxide ions perhaps that make cells not transport them??
Post Merge: 4 months ago
Quote from: bio_man (4 months ago)
Quote from: Dima Harba (4 months ago)
I tried it with ammonia and it changed colours so the indicator doesn't have limitations.
The fact that NH3 caused it to become yellow means there's evidence of transport into the cell. What you could do to determine if the yellow yeast cells are still alive by conducting a fermentation experiment or by observing the yeast cells bud after adding a glucose solution to the yellow yeast cells. When you applied sodium bicarbonate, did you apply any heating to the solution containing the cells? The only way the cells can become permeable to sodium bicarbonate is through heating, allowing the sodium bicarbonate to interact with the neutral red. Maybe your observations are correct. NaOH should keep the solution pink, creating no change.
Thanks! I tried heating it and it changed colour because the permeability increased. But regarding this part of the experiment I wasn't required to heat or do anything other than add NaOH. Is there an explanation to why the ions (especially OH-) didn't move through the channel proteins which don't require any energy?
Report
bio_man
wrote...
#7
Educator
4 months ago
Negatively charged ions aren't capable of moving through the membrane without help, especially a molecule like OH-. From experience, I've never heard of OH- molecules needing to pass through the membrane, that's why they weren't able to make a difference once you added hydroxide. Even facilitated diffusion via a channel not requiring ATP wouldn't be able to accomplish this.
1 Vote
Dima Harba
Report
The best way to say thank you is with a positive review:
https://trustpilot.com/review/biology-forums.com
Your support goes a long way!
▶
Make a note request here
Dima Harba
wrote...
#8
4 months ago
Quote from: bio_man (4 months ago)
Negatively charged ions aren't capable of moving through the membrane without help, especially a molecule like OH-. From experience, I've never heard of OH- molecules needing to pass through the membrane, that's why they weren't able to make a difference once you added hydroxide. Even facilitated diffusion via a channel not requiring ATP wouldn't be able to accomplish this.
. Oh. It's settled then. Thanks so much for your help!
Report
bio_man
wrote...
#9
Educator
4 months ago
Anything else, just holler!
See you around
Report
The best way to say thank you is with a positive review:
https://trustpilot.com/review/biology-forums.com
Your support goes a long way!
▶
Make a note request here
Dima Harba
wrote...
#10
3 months ago
Edited:
3 months ago, bio_man
Hello! I've been reading this post again and figured that I may have misunderstood you when you said ion concentration must be at equilibrium. Anyhow, I now understand what you mean but I have a simple question. Is the ion concentration determined by the amount or type of ions present in and outside the cell? Like is it the concentration of ALL ions inside the cell despite their type( for example sodium, hydrogen, or even potassium) that determine the ion concentration or like sodium ion concentration inside can be compared with ONLY sodium ion concentration on the outside?
Thanks in advance!
Report
bio_man
wrote...
#11
Educator
3 months ago
It's determined per EACH ion, not as a whole. For example, if the cell is permeable to sodium, what matters is if there's a gradient of sodium ions across the membrane, others don't matter.
Report
The best way to say thank you is with a positive review:
https://trustpilot.com/review/biology-forums.com
Your support goes a long way!
▶
Make a note request here
Dima Harba
wrote...
#12
3 months ago
Quote from: bio_man (3 months ago)
It's determined per EACH ion, not as a whole. For example, if the cell is permeable to sodium, what matters is if there's a gradient of sodium ions across the membrane, others don't matter.
Thanks a lot !
Report
New Topic
Quick Reply
[center][color=gray]Please [b]login or register[/b] to leave a reply[/color][/center]
Explore
Post your homework questions and get free online help from our incredible volunteers.
Why Sign Up?
Learn More
Improve Grades
Help Others
Save Time
Accessible 24/7
140 People Browsing
116 Signed Up Today
Start New Topic
Take the Tour
Study Tips
Browse by Textbook
New
Related Images
1053
802
71
Your Opinion
Do you trust social media networks with protecting your privacy?
Yes
No
Not sure
Votes: 22
Previous poll results:
What type of music do you study to?
Latest Blogs
Animal longevity correlated to these genes
Imperial and metric system facts lost in history
Top 5 Interesting Math Facts You Never Knew
Eyeless fish
A case for why teenagers make risky decisions
Ready to ask a question on
Biology Forums
?
Try it out
▸
[Free] - Chapter 07 - Womble: Introductory Mental Health Nursing 2nd Edition
–
Free Notes
A document (object in JSON terminology) consists of a set of ________ pairs.
–
Computer Studies
Chapter 2: Basic Pharmacology for Nurses, 16th Edition Test bank
–
Free Notes
[Free] - Chapter 09 - Womble: Introductory Mental Health Nursing 2nd Edition
–
Free Notes
Document databases have a well-developed theory and practice of database design.
–
Computer Studies
Data can be entered into an ArangoDB collection of documents by all of the following ways except ________.
–
Computer Studies
[Free] - Chapter 19 - Womble: Introductory Mental Health Nursing 2nd Edition
–
Free Notes
Chapter 1: Basic Pharmacology for Nurses, 16th Edition Test bank
–
Free Notes
Typical commands available in a document database include all the following except ________.
–
Computer Studies
[Free] - Chapter 16 - Womble: Introductory Mental Health Nursing 2nd Edition
–
Free Notes
Loading...