Ch. 9 Flashcards
What is a genome?
-the sum total of genetic material of an organisms
What are examples of what’s included in a genome?
- -most in chromosome form
- -or non-chromosomal sites like: Plasmids(tiny extra pieces of DNA) and organelles(mitochondria and chloroplast)
What is a phenotype?
- the expression of the genotype that creates certain structures of function.
What is a genotype?
-the sum of all types of genres constituting an organisms distinctive genetic makeup
Describe prokaryotic chromosomes.
Chromosome consists of double–stranded circular DNA. Prokaryotes do not contain nucleus or other membrane bounded organelles. The term “prokaryotes” actually means “before nucleus”. Chromosome is stored in a special area called nucleoid.
Describe eukaryotic chromosomes.
Eukaryotic chromosomes consist of a DNA-protein complex that is organized in a compact manner which permits the large amount of DNA to be stored in the nucleus of the cell. The subunit designation of the chromosome is chromatin
Structure and make-up of DNA.
DNA is made up of six smaller molecules – a five carbon sugar called deoxyribose, a phosphate molecule and four different nitrogenous bases (adenine, thymine, cytosine and guanine).
Structure and make-up of RNA.
Single-stranded. Like DNA, RNA is composed of its phosphate group, five-carbon sugar (the less stable ribose), and four nitrogen-containing nucleobases: adenine, uracil (not thymine), guanine, and cytosine.
What is a gene?
- basic informational packets
- a segment of DNA that contains the necessary code to make a protein or RNA
What is the process of DNA replication?
- process of producing two identical replicas of DNA from one original DNA molecule.
- DNA is made up of a double helix of two complementary strands. During replication, these strands are separated.
What is the function of DNA polymerase?
The main function of DNA polymerase is to make DNA from nucleotides, the building blocks of DNA. There are several forms of DNA polymerase that play a role in DNA replication and they usually work in pairs to copy one molecule of double-stranded DNA into two new double stranded DNA molecules.
What is the function of DNA ligase?
DNA ligase is an enzyme that repairs irregularities or breaks in the backbone of double-stranded DNA molecules. It has three general functions: It seals repairs in the DNA, it seals recombination fragments, and it connects Okazaki fragments (small DNA fragments formed during the replication of double-stranded DNA).
What is the function of DNA helicase?
DNA helicase continues to unwind the DNA forming a structure called the replication fork, which is named for the forked appearance of the two strands of DNA as they are unzipped apart. The process of breaking the hydrogen bonds between the nucleotide base pairs in double-stranded DNA requires energy.
What is the function of DNA gyrase?
DNA gyrase is an essential bacterial enzyme that catalyzes the ATP-dependent negative super-coiling of double-stranded closed-circular DNA.
What is the function of RNA polymerase?
is an enzyme that produces primary transcript RNA. In cells, RNAP is necessary for constructing RNA chains using DNA genes as templates, a process called transcription.