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AGHS - CP Bio - Agar Cube Lab

Last updated almost 5 years ago
13 questions
Note from the author:
why cells are small a virtual lab

Agar Cube Lab

The goal of this lab is to get you thinking about cell sizes and why cells are limited in how large they can grow. To link it to the cell cycle, you're going to explain WHY cells that move out of G1 are committed to completing the cell cycle and MUST divide!
PART 1- AGAR CUBE LAB OBSERVATIONS AND CRITICAL THINKING QUESTIONS
1

After cells exit G1 and move through S and G2, what happens to the size or volume of a cell?

1

In the video demonstration the lab, the cubes were made using a chemical indicator that turns pink when a substance's pH is basic or alkaline.

Based on this information, what could the pH of the agar cubes have been at the start of the lab?

1

In the video demonstration the lab, the cubes were submerged in a acidic solution made by mixing vinegar and water. As the solution diffused into the cubes it turned them clear indicating the pH of the cubes had changed and became more acidic.

Based on this information, what could the pH of the agar cubes have been at the end of the lab?

1

What happened to the smallest cube by the end of the video?

1

Why did this happen?

1

This lab is a model of cells obtaining the materials they need from their surrounding environment so what do the results indicate? Select all that are true!

1

What happened to the larger cubes by the end of the video?

1

What would likely happen to these "cells" using the knowledge you showed in question 6?

1

In your own words, explain why a cell that has compelted the S and G2 phases of the cell cycle MUST continue through the M-phase in order to function properly.

PART 2- AGAR CUBE LAB EXPLAINED
You deserve to hear the entire explanation about the results of this lab. To do so, check out this video by Mr. W (yes the man who brought you the world's catchiest biology jam "Glycolysis!"). Don't worry he won't serenade you this time :-)
If you want to change any of your answers above feel free to since Mr. W discussed all of the science !
1

What MUST be true about the surface area to volume ratios in living organisms to increase their efficiency?

1

We always think that cells are small but neurons/nerve cells can be over one meter long! These lengthy cells are in the nerves that run down the back of your leg and allow you to flex your feet! What must be true about them to permit them to be so long?

PART 3- APPLYING SURFACE AREA TO VOLUME RATIOS TO REAL LIFE
The concept of high surface area to volume ratios isn't helpful just for cells! It is emplyed by many species in the animal kingdom too! Here are some real life applications of the concept explained above as well as some examples of when have low surface area to volume ratios can be beneficial!
5

Organize the animal example given in the video to the type of surface area to volume ratio it uses.

  • temperature regulation of elephants using large, flat ears
  • humans pulling their arms in close to their core when they're cold
  • diffusion of oxygen into and carbon dioxide out of flatworms
  • the cells that line your small intestines have many tiny projections called microvilli to help you absorb nutrients
  • whales are large in size to prevent heat loss
  • having a high amount of surface area compared to volume is helpful in these examples
  • having a low amount of surface area compared to volume is helpful in these examples
3

These are not the only examples organisms using the idea of high surface area to volume ratios. There are MANY more!

Think of, or research to find, ONE new example of a living organism that uses having a high amount of surface area and a lower amount of volume to increase its efficiency. Be sure to identify the organism as well as the benefit of the adaptation. There are others in your human body and many more on the tree of life. You can use plants too! No credit will be given for repeating information that was included in the Mr. W videos!