exam 3 Flashcards
(28 cards)
What happens to all cells eventually?
All cells stop growing and splitting
This is due to the limitations in transporting materials and the demands placed on DNA.
What is cell division?
Process where a single cell divides into two new cells called daughter cells
Each new cell is an identical version of the original cell.
What are sarcomas?
Tumors from cells in connective tissue, bone, or muscle
These are a type of cancer.
What are carcinomas?
Tumor cells from epithelial tissue such as skin or lining of the lung
These are also a type of cancer.
What is binary fission?
The main type of asexual reproduction
Other types include budding, vegetative propagation, spore formation, and fragmentation.
What are the pros of asexual reproduction?
- Simple
- Quick
- Effective
- Lowered chance of genetic disorders
Common in prokaryotic organisms and some eukaryotes.
What is sexual reproduction?
Fusion of reproductive cells from two parents (egg + sperm)
Genetic information comes from both parents.
What is the purpose of interphase?
Preparation for the cell to be split
Consists of copying DNA and cell growth.
What are the four parts of interphase?
- G0 - cells not actively dividing
- G1 - prepares to copy DNA
- S phase - DNA molecules are copied
- G2 - preparations for mitosis
Dysfunctional cells are often discarded during this phase.
What is mitosis?
The process to divide the nucleus resulting in identical somatic cells
It is essential for growth and repair.
What happens during prophase?
Nucleus condenses and chromosomes become visible; the spindle begins to form
This is the first stage of mitosis.
What is the primary difference between diploid and haploid cells?
- Diploid - Two complete sets of chromosomes (2n)
- Haploid - Half of a set of chromosomes (n)
Ex: Skin cells are diploid, sex cells are haploid.
What is meiosis?
Process used to make haploid cells involving two phases of division
Results in four haploid cells.
What is the central dogma of molecular biology?
DNA to RNA to Protein
This describes the flow of genetic information in a cell.
What are the components of nucleic acids?
- Hydrogen
- Oxygen
- Nitrogen
- Carbon
- Phosphorous
They play a large role in genetics.
What is the structure of DNA?
Double stranded with deoxyribose sugar
Contains nitrogenous bases: adenine, thymine, cytosine, and guanine.
What is the structure of RNA?
Single stranded with ribose sugar
Contains nitrogenous bases: adenine, uracil, cytosine, and guanine.
What is the purpose of DNA replication?
To replicate or make copies of DNA
It uses the semiconservative model.
What is the role of RNA in protein synthesis?
Transfers genetic information from the nucleus to ribosomes
This is essential since DNA is confined to the nucleus in eukaryotes.
What is transcription?
The process where RNA is synthesized from a DNA template
RNA is complementary to the DNA, with uracil replacing thymine.
What are the stages of transcription?
- Initiation
- Elongation
- Termination
Each stage has specific events that facilitate RNA synthesis.
What is gene regulation?
The process by which genes are turned on and off
It leads to cell specialization in eukaryotes.
What is the function of ribosomes?
Site of protein synthesis
They organize, bind, and read the sequence of nucleotides in mRNA.
What is the difference between prokaryotic and eukaryotic translation?
In prokaryotes, translation occurs immediately after mRNA transcription; in eukaryotes, it does not
This results from the compartmentalization of the nucleus in eukaryotic cells.
