Chapter 10 Flashcards
What size cells are most efficient?
Small cells.
What is cell division?
Cell division is when a cell divides into two clone cells.
Why do cells divide rather than grow?
Larger cells need more DNA and larger cells have more difficulty moving nutrients and waste across the cell membranes, so to avoid these issues they remain small.
How many cells are produced each day in an adult human?
2-Trillion Cells
How does Bacterial Cell Reproduction work?
They reproduce by Binary Fission, a form of asexual reproduction.
What are the two steps in Bacterial Cell Reproduction?
First DNA is copied and then the cell divides.
What are genes?
A segment of DNA that codes for a protein or a RNA molecule.
What is DNA?
Nucleic acid that stores hereditary information. DNA also contains thousands of genes.
What are chromosomes?
Structures made of DNA and associated proteins on which genes are located.
What are chromatids?
One pair of strands of DNA that make up a chromosome.
What is the centromere?
The region where the two chromatids meet.
What is the Cell Cycle?
A repeating sequence of cell growth and division during the life of an organism.
What is the G₁ phase?
The phase in the cell cycle where the cell doubles in size and synthesizes protein and organelles.
What is the S phase?
The phase where the cell’s DNA is copied.
What is the G₂ phase?
The phase where genetic material begins to condense, centrioles are replicated, and microtubules are arranged. Preparations to divide also begin in the nucleus.
What is the Mitosis phase?
The phase where the nucleus is divided.
What is the Cytokinesis phase?
The phase where the cytoplasm of the cell is divided.
What are the G₁, S, and G₂ phases called?
Interphase
What are spindles?
Cell structures that are made up of centrioles and individual microtubule fibers.
What do spindles do?
Spindles move chromosomes during cell division.
What happens in the first stage of Mitosis?
Chromosomes become visible, the nuclear envelope becomes visible, and spindles form.
What happens in the second stage of Mitosis?
Chromosomes move to the center of the cell to line up along the equator and spindles link the chromatids to opposite centrioles.
What happens in the third stage of Mitosis?
The sister chromatids are separated from each other and are pulled toward the polar centrioles.
What happens in the fourth stage of Mitosis?
The nuclear envelope forms around the chromosomes at each pole and the spindles dissolve.
What are the four stages of Mitosis called?
Prophase, Metaphase, Anaphase, and Telophase. (In this order)
Where are the three checkpoints for regulating the cell cycle?
The first checkpoint is after the G₁ phase, which decides if the cell should even divide. The second is before the G₂ phase and checks to make sure DNA is synthesized correctly. The third is checking to make sure the cell can leave mitosis.
Based on space, when will a cell divide?
Cells can only divide if there is space.
What are cyclins?
Cell-Cycle Regulators.
What are Internal Regulators?
Proteins that respond to evens inside the cell, such as checkpoint proteins.
What are External Regulators?
Proteins that respond to events outside the cell such as growth factors.
What is the name of the disease that occurs when cells divide rapidly?
Cancer.
What is the Deletion mutation?
When one or more nucleotides on a chromosome are removed.
What is the Duplication mutation?
When a chromosome will carry two copies of a gene.
What is the Inversion mutation?
When a chromosome reattaches in a reverse orientation on a homologous chromosome.
What is the Translocation mutation?
When a chromosome reattaches on a nonhomologous chromosome.
