Structure and Function of Cells
__________________ is the basic unit of structure and function in living things (organisms).
Cells
Mad cow disease is caused by deformed proteins called prions. The disease is spread when meat from an infected cow is eaten. Prions can make normal proteins deform into more prions. After a few years, the brain of an infected person or cow looks like a sponge full of holes.
Are prions considered organisms (living things)?
No, because proteins are not made of cells (so therefore non-living)
Diffusion is the process of molecules from areas of _________________ concentration to areas of _______________ concentration
High concentration to low concentration.
What is happening in the cell during Metaphase?
The chromosomes line up down the middle of the cell.
Without the invention of which piece of technology would the cell theory have not been possible?
The Microscope
How are unicellular and multicellular organisms different?
unicellular- 1 cell that performs all functions necessary to keep the organism alive.
multicellular- many cells that have specific functions to perform to keep the organism alive
A Cell membrane is semi-permeable. What does it mean to be semi-permeable?
Some molecules/particles are allowed through, while others are kept out.
Last week, we completed a lab demonstrating Osmosis with an egg (to represent a cell). Explain how osmosis was observed in that lab.
Osmosis is the process where molecules move across a membrane. In the case of our egg, the liquids moved into and out of the cell depending on the concentration. With the vinegar, the concentration was higher outside of the egg so it absorbed (took in) vinegar and increased in size (mass). When placed in corn syrup, the concentration was higher inside than outside, so the egg lost water. In the water, it again increased in size (more water outside so it entered through the membrane).
Which phase of the cell cycle do cells spend the most of their time in?
Prophase, Metaphase, Anaphase, Interphase, Mitosis
Interphase
When DNA condenses into X shaped structures they are called_________________
Chromosomes
What are the three main ideas behind the cell theory?
1. All living things are made of cells.
2. Cells are the basic unit of structure and function in living things.
3. All new cells are produced from existing cells.
What are the two structures (organelles) that are found in plant cells BUT NOT in animal cells?
Cell Wall
Chloroplast
Talitha is performing an experiment on how plants get water up to their leaves. She adds two drops of blue food coloring to a beaker of water. Then, she hears a fire alarm and heads outside. When Talitha gets back to the classroom, the water in the beaker is all pale blue.
She recognizes that the process of __________________ has caused the dye to spread evenly through the water.
Diffusion
The Cell Cycle (Cell Division) includes 3 main parts. What are the three main parts?
Interphase
Mitosis
Cytokinesis
Corn Syrup and salt are examples of which types of solutions?
Hypertonic (They have more concentrate in their solution than they do water). They cause the things put in them to shrink.
Your body is made up of trillions of cells that perform all the functions you need to survive. Which other kinds of organisms are composed of cells?
All living things (organisms) are made of cells
The ghost plant is white with a single stalk. Even though it looks more like a mushroom, the ghost plant is related to blueberry plants. The ghost plant is a parasite that feeds on fungi under the ground.
Ghost plant cells have all the usual plant organelles except for a
Chloroplast
Explain how diffusion works
Diffusion is the spreading of molecules when they move from an area of high concentration to an area of low concentration until the amounts in both areas are equal.
What are the 4 phases of Mitosis?
Prophase
Metaphase
Anaphase
Telophase
Terry and James are partners in a mystery lab. The boys have a compound light microscope and several unlabeled slides. Their task is to find out everything they can about the samples on the slides. Terry puts a slide on the microscope stage and focuses the lenses on the sample. He can see that the sample is made up of tiny cells.
James looks into the microscope and sees that Terry has done a good job of focusing on the sample, but the cells are still too small to see much detail. James looks again at the microscope and figures out a way to see the cells much better.
Predict how James will improve the view of the sample. How will the magnification and resolution of the image change?
James would adjust the lens that is being used. THis will change the magnification. James would then adjust the knobs to focus the item in (and increase the resolution or clarity) of the samples.
Terry and James are partners in a mystery lab. The boys have a compound light microscope and several unlabeled slides. Their task is to find out everything they can about the samples on the slides. Terry puts a slide on the microscope stage and focuses the lenses on the sample. He can see that the sample is made up of tiny cells.
Terry wishes he could magnify the cells even more so he could see more details. He suggests, “If we had an electron microscope, we could see all of the cells inside these cells, and even the cells inside those smaller cells!”
James disagrees with Terry's thinking. What is wrong with Terry’s suggestion?
Cells are the basic unit of life and they do not have more cells inside them. Cells are the smallest things we are able to see in a living organism.
A virus can reproduce only inside a cell. Once inside, the virus causes the cell to make many new copies of the virus.
In an animal, which part of the cell is responsible for keeping viruses out?
The Cell Membrane
In our Gizmos Case Study where we looked at the Cow that had seizures, how was osmosis responsible for the seizures?
Osmosis caused water to enter the brain, increasing the pressure which leads to neurons not firing properly and causing the seizures. Using a saline solution lowered the concentration and the pressure and helped with the seizures.
Why is Mitosis (Cell Division) important to the survival of organisms?
Cell division is important for Growth, Development and tissue repair in organisms and their cells.
Why is maintaining homeostasis important to a healthy organism?
Homeostasis is where the internal and external environments are equal. This causes things to function properly. If there is too much or too little, this can cause various issues within the cells and the organism.