Biology 189- DNA Replication/Chapter 8
binary fission steps
1. DNA is replicated 2. Each prokaryotic cell contains one circular chromosome 3. As the cell prepares to divide, its DNA replicates 4. The chromosome and its duplicate attach to the inner surface of the cell. 5. The cell membrane grows between the two DNA molecules, separating them. 6. Then the cell pinches them in half to form two daughter cells from the original one.
What is a karyotype?
A display of every pair of homologous chromosomes within a cell, organized according to size and shape
Telophase (Mitosis Phase 4)
A nuclear membrane forms around each set of chromosomes, and the chromosomes unwind. Mitosis is complete.
What is a centromere?
A small region of a chromosome where sister chromatids attach to each other
How does cell theory relate to mitosis and binary fission?
All cell come from pre existing cells through cell division.
How do proteins know where to begin DNA replication on the genome?
Because chromosomes have their associated proteins.
Prophase (Mitosis Phase 1)
Chromosomes become visable, nuclear envelop dissolves, spindle forms
Metaphase (Mitosis Phase 2)
Chromosomes line up in the middle of the cell
Which domains do not reproduce by sexual means?
Domain bacteria and Domain archae
S phase
Enzymes replicate the cell's genetic material and repairs damaged DNA.
True or false? All DNA sequences are coding?
False
What is the cell cycle?
Interphase, Mitosis, and Cytokinesis. series of events that cells go through as they grow and divide
How are cell cycle stages ordered?
Interphase- G1, S, G2 phase Mitosis- Prophase, Metaphase, Anaphase, Telephase Cytokinesis
G1 phase
The cell grows, carries out its basic functions, and produces the new organelles and other components it will require if it divides.
Anaphase (Mitosis Phase 3)
The chromatids separate and move to opposite sides of the cell
horizontal transfer
The transfer of DNA from one cell to another by a process other than cell division, such as bacterial conjugation
True or false. In a dividing cell DNA is condensed?
True
What is a gene?
a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring.
What would happen if a cell could not transition to the next stage?
cell death
G2 phase
cells continue to grow, but also prepares to divide.
Difference between chromatin and chromosomes?
chromatin- unwound and chromosomes are wound Chromatin- DNA and its associated proteins Chromosomes- A single continuous molecule of DNA wrapped around proteins. Eukaryotic cells contain multiple linear chromosomes, whereas bacterial cells typically have one circular chromosome.
Cytokinesis
division of the cytoplasm to form two separate daughter cells, which then physically separate.
Mitosis
division of the nucleus
What are the different stages of cell cycle?
interphase, mitosis, cytokinesis
Cells die in two ways
necrosis and apoptosis
What are homologous chromosomes?
paired chromosomes with genes for the same traits arranged in the same order
Why do cells need to divide?
repair damaged tissues, replace damaged worn out cells, immunity, growth, reproduction, keep surface area to volume ratio large
What are sister chromatids?
structures that contain identical copies of DNA
What is gene expression?
the way in which DNA, RNA, and proteins are involved in putting genetic information into action in living cells
What is a karyotype used for?
used to examine an individuals chromosomes
How are genes, chromosomes, and DNA related?
Genes are segments of DNA found on chromosomes
What proteins are involved in DNA replication and what are their specific functions?
Helicase enzyme- unwind and "unzip" the DNA molecule Polymerase enzyme- adds new DNA nucleotides that are complementary to the bases on each exposed strand.
