Cell Theory
What is a scientific theory?
A big idea that is tested and proven, following many experiments and observations.
The ______ controls what enters and leaves the cell
Cell Membrane
Define homeostasis
A state of balance in the body
If a cell has 13 duplicated chromosomes after S phase, how many chromatids does it have?
26 chromatids
What are cancer cells and how does their formation relate to the cell cycle?
Cancer cells are cells that divide uncontrollably. They often ignore the cell cycle checkpoints, leading to abnormal growth.
What are the levels of organization in multicellular organisms?
Organelles --> cells --> tissues --> organs --> organ systems --> living organism
Describe the function of the cytoskeleton
Gives a cell its shape, offers support, and facilitates movement.
What are the 6 stages of the cell cycle
Mitosis, G2, G1, S, G0, Interphase
What would happen to a cell if it reached a checkpoint and it was determined that the cell had not copied its DNA correctly or it hadn't divided correctly?
The cell would activate repair mechanisms. If it can't be fixed, it either self-destructs, or undergoes apoptosis.
True or False: Only animal cells are composed of cells
False
How does the mitochondria contribute to a cell's function?
The powerhouse of the cell, generate most of the cells energy.
What is an example of positive feedback?
Childbirth, blood clotting, lactation, fruit ripening
Mitosis is a part of the cell cycle where a cell divides to create two identical cells. It's crucial for growth and repair.
How are malignant tumors formed?
When cells progress through the cell cycle, without passing through the checkpoints that are making sure everything is okay.
What is the most essential organelle in the cell?
Ribosomes
What cells do animal cells have that plant cells do not
Centrioles and lysosomes
How does the cell membrane help with homeostasis?
Keeps balance of proteins, nutrients, water, etc. inside and outside of the cell
Why do animal/plant cells need to divide?
Cell division helps in growth, repair, and reproduction in both plant and animal cells.
Harvey was a perfectly happy baby with normal development until 6 months of age. A neurologist diagnosed him with Tay-Sachs disease, which caused built up fatty material on his nerve cells that his cells could not break down. What organelle is malfunctioning?
Lysosomes
They are not breaking down harmful fatty molecules that are building up in the cell.
What are the three principles of cell theory?
1. All organisms are made of cells
2. Cells are the basic unit of life
3. Cells come from pre existing cells
What is the difference between cilia and flagella?
Cilia are short and numerous, that help move substances around the cell. Flagella are longer, fewer, and move the cell itself.
Give 3 examples of how your body maintains homeostasis
Interphase, prophase, metaphase, anaphase, telophase.
Jackie was 4 months old when her head became disproportionally large for her face. She experienced hair loss, and her skin became thin and wrinkled. Jackie's doctors told her that her condition was progeria, which occurs when the genetic material doesn't have proper protection. What organelle is malfunctioning?
Nucleus
The nucleus is not protecting the DNA, so it causes damage to the DNA and premature aging in cells.