MS Science Virtual Classroom

Wednesday, January 23, 2013

VDA #6

1. Scientists predict that prune fingers may serve a purpose. What purpose do they suggest prune fingers serve?

The purpose scientists predict prune fingers serve are that prune fingers improve our fingers' ability to grasp wet, slippery objects.

2. Do you think that the study performed in England was a valid study? Why or why not?

I think the study in England was valid because it showed that every participant moved the wet objects faster with wrinkled fingers. However, the study also showed that wrinkled skin didn't help any of the participants move the dry objects any faster.

3. How would you design an experiment to gather more data to support the suggestion that prune fingers serve a purpose? (Be sure to include the number of people sampled, the independent and dependent variables and the duration of time for your experiment.)

I could design an experiment in several ways. One way I could do the experiment is, I could have 40 people. I would ask them to soak their fingers in warm water for five different periods of time. One period for 1 minute, one period for 5 minutes, one period for 10 minutes and one period for 15 minutes. I would then ask and time the participants to move a few wet objects from one box to another and see if the time difference or the more wrinkly your fingers are the easier and faster it is to hold and move objects. My independent variable would be the different times and my dependent variables would be the water, participants, and objects. The time for my experiment would be about 35-40 minutes long. Another experiment I could do would be similar to the first, except I could use salt water and fresh water and test the differences between the two different waters. I would have 40 participants that would test both waters for different amounts of time and see which water and time difference helps in grasping wet slippery objects. My independent variables is the salt water, fresh water, and time; my dependent variables would be the participants and objects. My time would be about the same 35-55 minutes.

4. What biological process allows for the skin on our hands and feet to turn wrinkly in the first place?
The process that allows the skin on our hand and feet to get wrinkly is because of sebum. Sebum is an oil that covers our skin. Sebum is found on the most outer most layer of skin. Sebum moistens and protects your skin. It makes your skin more waterproof. When you are in the water for a long period of time the water washes away the sebum, this causes the skin to become waterlogged and trap in water which makes our hands wrinkly. (Downshen, MD, 2010)

REDO:
2.Do you think that the study performed in England was a valid study? Why or why not?
I think the study in England was valid andbecause it had before and after data. The study also had experimental and control groups. the partcipants did the experimant twice, once with dry hand, and once with wet, wrinkly hands. The experiment also has independent and dependent variables.

3. How would you design an experiment to gather more data to support the suggestion that prune fingers serve a purpose? (Be sure to include the number of people sampled, the independent and dependent variables and the duration of time for your experiment.)
My experiment would be that I would have 40 participants. I would have the participants test two different types of water; saltwater and freshwater. I would have two groups. Twenty people would soak their hands for 30 minutes in saltwater; this is my experimental group. Twenty people would soak their hands for 30 minutes in freshwater, this is my control group. After this step, I would ask the participants to move several objects from one box to another and time which group moves the objects fastest. It would either be the fresh water or saltwater group.The time for my experiment would be about 35-40 minutes. My independent variables would be the saltwater and fresh water. My dependent variable would be the task or how fast my participants would take to move the objects from one box to the other box. 

4. What biological process allows for the skin on our hands and feet to turn wrinkly in the first place?
The biological process is called osmosis.