Chapter 1 - An evolving science Flashcards
Biological macromolecules
Large molecules such as proteins and nucleic acids.
Metabolites
Low-molecular weight molecules such as glucose and glycerol.
The 3 fundamental domains
Eukarya, Bacteria, Archaea
The defining characteristic of eukaryotes is
The presence of a well defined nucleus in each cell.
Prokaryotes
Unicellular organisms that lack a nucleus.
Monomer
A molecule that can be bonded to other identical molecules to form a polymer.
4 DNA monomers
adenine, cytosine, guanine, thymine
The DNA backbone is built of
repeating sugar-phosphate units.
In DNA, the sugar is
deoxyribose.
In DNA, each sugar is connected to
two phosphate groups through different linkages.
DNA base pairs are held together by
hydrogen bonds.
Adenine pairs with
Thymine
Guanine pairs with
Cytosine
Adenine structure
Thymine structure
Guanine structure
Cytosine structure
A system refers to
the matter within a defined region of space.
The surroundings refers to
the matter in the rest of the universe that is not in the system.
First Law of Thermodynamics
The total energy of a system and its surroundings is constant.
Second Law of Thermodynamics
The total entropy of a system plus that of its surroundings always increases.
What is hemoglobin’s role in the body?
Carries oxygen in our blood.
On average, each pair of individuals has a different base in one position in their DNA approximately
one out of every 200 bases.
2 primary ways DNA and protein differ.
- Proteins have 20 building blocks while DNA has 4.
- Proteins spontaneously fold into elaborate three-dimensional structures.
What determines the structure of a protein.
The sequence of its amino acids.
The fundamental unit of hereditary information is the
gene.
The genes that are the simplest to define encode the sequences of
proteins.
Codon
A sequence of three nucleotides which together form a unit of genetic code in a DNA or RNA molecule.
Genetic code
The set of rules that links the DNA sequence to the encoded protein sequence.
Approximate number of protein-encoding genes.
20,000-25,000
The protein-encoding region accounts for approximately ____% of the human genome.
3
