D1.2 SL / HL Flashcards
DNA
a molecule that contains the genetic information for an organism’s development and function
RNA
a nucleic acid that carries genetic information and is present in all living cells
genes
a segment of DNA that contains instructions for making proteins
transcription
the process of making an RNA copy of a gene’s DNA sequence.
RNA polymerase
an enzyme that is responsible for copying a DNA sequence into an RNA sequence, duyring the process of transcription
promoter sequence
DNA sequences that define where transcription of a gene by RNA polymerase begins
template strand
a DNA strand that serves as a guide for making a complementary strand of RNA or DNA
complementary base-pairing rules
adenine will always pair with its complement thymine and cytosine will always pair with its complement guanine
mRNA
a single-stranded RNA molecule that carries genetic information from DNA to the cytoplasm of a cell
tRNA
a small RNA molecule that helps build proteins by carrying amino acids to the ribosome
rRNA
a type of RNA that’s a key component of ribosomes, which are responsible for protein synthesis
ribozymes
a ribonucleic acid (RNA) molecule that acts as an enzyme to speed up chemical reactions
ribosomes
organelles that are made of RNA and protein, and are responsible for protein synthesis in cells
Sense strand
a DNA strand that contains the code for making proteins
Anti-sense strand
a non-coding DNA strand that serves as a template for producing messenger RNA (mRNA)
mutations
a change in the DNA sequence of an organism
somatic cells
the cells in the body other than sperm and egg cells
gametes
reproductive cells, also known as sex cells, that are used during sexual reproduction
Gene expression
the process by which the information encoded in a gene is turned into a function. This mostly occurs via the transcription of RNA molecules.
differentiation
the process by which immature cells develop into mature cells with specific functions
cytoplasm
the fluid that fills the inside of a cell, excluding the nucleus
nuclear pores
a protein-lined channel in the nuclear envelope that regulates the transportation of molecules between the nucleus and the cytoplasm
prokaryotes
any organism that lacks a distinct nucleus and other organellesdue to the absence of internal membranes
peptide bonds
a covalent bond that joins amino acids together to form polypeptides and proteins
Small ribosomal subunit
a part of a ribosome that decodes genetic information.It’s responsible for the first step of protein synthesis, called initiation
Large ribosomal subunit
the larger of the two subunits that make up a ribosome.It’s responsible for linking amino acids together to form a polypeptide chain
A-site (amino)
a binding site on a ribosome where transfer RNA (tRNA) molecules attach during protein synthesis
P-site (peptidyl)
a binding site in the ribosome that holds the tRNA carrying the growing polypeptide chain during protein synthesis
E-site (exit)
a binding site on the ribosome where uncharged transfer RNA (tRNA) exits after donating its amino acid during protein synthesis
Triplet
a sequence of three bases in DNA or RNA that codes for a specific amino acid
codon
mRNA sequence of three nucleotides(a trinucleotide) that forms a unit of genomic information encoding a particular amino acid
anticodon
a sequence of three nucleotides that matches a codon in messenger RNA (mRNA).Anticodons are found in transfer RNA (tRNA) molecules.
Degenerate code
when multiple codons can code for the same amino acid
start codon (AUG)
a sequence of three nucleotides in messenger RNA (mRNA) that signals the start of protein synthesis
methionine (Met)
an essential amino acid that contains sulfur and is vital for protein synthesis
stop codon (UAA, UGA, and UAG)
a sequence of three nucleotides (UAA, UAG, or UGA) that signals the end of protein synthesis in a cell
Base substitution mutation
a genetic mutation that occurs when a single base in DNA is swapped for another
Point mutation
A genetic alteration caused by the substitution of a single nucleotide for another nucleotide
Genetic disease
a disease caused in whole or in part by a change in the DNA sequenceaway from the normal sequence
Hemoglobin
an iron-rich protein in red blood cells that carries oxygen from the lungs to the body’s tissues and organs
Hb gene
genes that code for the proteins that make up hemoglobin, a protein in red blood cells that carries oxygen
alleles
different versions of a gene that occur at the same location on a chromosome
HbA (normal)
the main type of hemoglobin in healthy adult red blood cells
HbS (sickle shape)
an abnormal form of hemoglobin that causes red blood cells to sickle, or curve into a crescent shape
Sickle cell disease
a genetic blood disorder that causes red blood cells to become misshapen and sickle-shaped
