DNA Structure and Function Flashcards
Where are nuclei found?
The cells of eukaryotes
What are nuclear pores?
Pores in the double membrane of the nucleus
What is inside the nucleus?
The nucleoplasm, nucleolus, and chromatin network
What is the chromatin network?
A mass of thread-like structures made of DNA suspended in the nucleoplasm
What is the function of the nucleus?
Regulate cell structure and metabolism
Contain DNA
Allow for cell division
What are the two types of nucleic acid?
DNA and RNA
Where can extranuclear DNA be found?
The mitochondria (mtDNA) and chloroplast (cpDNA) in plants
What do nucleic acids consist of?
Monomers called nucleotides
Define eukaryote
Organisms whose cells have a nucleus enclosed within a nuclear envelope
Define metabolism
The chemical reactions in the body’s cells that change food into energy
Define genes
A unit of heredity which is transferred from a parent to offspring and is held to determine some characteristic of the offspring.
What is an organelle?
a subcellular structure that has one or more specific jobs
What is cytoplasm
The thick solution that fills each cell
What is a polymer?
Substance with a molecular structure built up by many repeating sub-units.
What is a monomer?
A molecule that can bond with other monomers to form a polymer.
What are nucleotides?
The monomers which make up DNA.
What is deoxyribose sugar?
The five-carbon sugar molecule that helps form the phosphate backbone of DNA molecules.
Define phosphate group.
The “middle man” between two adjacent deoxyribose sugars.
What is a nitrogenous base?
A molecule that contains nitrogen and has the chemical properties of a base. (ATCG)
What is adenine?
One of the larger (purine base) nitrogenous bases.
Always pairs with thymine.
What is thymine?
One of the smaller (pyrimidine base) nitrogenous bases.
Always pairs with adenine.
What is cytosine?
One of the smaller (pyrimidine base) nitrogenous bases.
Always pairs with guanine.
What is guanine?
One of the larger (purine base) nitrogenous bases.
Always pairs with cytosine.
Define a hydrogen bond.
The attraction between a partially positively charged hydrogen atom attached to a highly electronegative atom (such as nitrogen, oxygen, or fluorine) and another nearby electronegative atom.
Define genome
Complete set of genes in an organism.
What is non-coding DNA
DNA that does not code for proteins (not genes).
Functions of non-coding DNA
Regulates/controls gene expression
Protects genes from mutation
Controls transcription of DNA during protein synthesis
