Unit 3 - AOS1 - CH.1 Flashcards
Active transport
Net movement of dissolved substances across a cell membrane by an energy-requiring process that moves substances against a concentration gradient from a region of low to higher concentration.
Alpha helix
A type of secondary structure in proteins that appears as a tight twist.
Alternative splicing
Production of different mRNA molecules from one kind of pre-mRNA through joining various combinations of exons from the pre-mRNA
Amino Acids
Basic building blocks or sub-units of polypeptide chains and proteins
Anticodon
Sequence of three bases in a transfer RNA molecule that can pair with the complementary codon of a messenger RNA molecule
Beta-pleated sheet
A type of secondary structure in proteins that appears as folded sheets, with a change in direction of the polypeptide chain. .
Carbohydrate groups
Molecules that are associated with the plasma membrane and are associated with cell to cell communication.
Coding region
Part of a gene that contains the coded information for making a polypeptide chain
Coding strand
One strand of a DNA double helix that is complementary to the template.
Codons
Sequences of three bases in a messenger RNA molecule that contain the information either to bring amino acids into place (in a polypeptide chain) or start or stop this process.
Polypeptide chain
A single linear chain of many amino acids bonded together
Conjugate
A condition in which amino acids of a protein, particularly proteins in the nucleus, associate with other groups.
Degenerate
The property of the genetic code in which more than one triplet of bases can code or one amino acid.
Deoxyribonucleic acid (DNA)
Nucleic acid consisting of nucleotide sub-units that contain the sugar deoxyribose and the bases A,C,G and T; DNA forms the major component of chromosomes.
Endocytosis
An energy-requiring process of bulk transport, in which solids or liquids move into the cell by engulfment
Endoplasmic reticulum
Cell organelle consisting of a system of membrane-bound channels that transport substances within the cell.
Eukaryotes
Any cells or organisms with a membrane-bound nucleus
Eukaryotic cells
Cells within eukaryotes that have a membrane-bound nucleus and other membrane-bound organelles.
Exocytosis
An energy-requiring process of bulk transport, in which solids or liquids move out of the cell via vesicles.
Exons
Parts of the coding region of a gene that are both transcribed and translated.
Exon juggling
Production of different combinations of the exons in a gene transcript leading to different gene products from the same gene.
Facilitated diffusion
Form of diffusion involving a specific carrier molecule for the substance.
Flanking regions
Regions located either downstream or upstream of the coding region of a gene.
Fluid mosaic model
A model which proposes that the plasma membrane and other intracellular membranes should be considered as two-dimensional fluids in which proteins are embedded.
Genetic code
Representation of genetic information through a non-overlapping series of groups of three bases (triplets) in a DNA template chain.
Golgi Apparatus
Organelle that packages material into vesicles for export from a cell (also known as Golgi complex or Golgi body)
Hydrophilic
Substances that dissolved easily in water; also termed polar
Hydrophobic
Substances that tend to be insoluble in water; also termed non polar
Integral proteins
Proteins that are embedded in the phospholipid bilayer
Introns
Parts of the coding region of a gene that are transcribed but not translated
Lysosomes
Membrane-bound vesicles containing digestive enzymes
Messenger RNA (mRNA)
Form of RNA synthesises by transcription of a DNA template strand in the nucleus; mRNA carries a copy of the genetic information into the cytoplasm.
Nucleoproteins
Proteins associated structurally with nucleic acids.
Nucleotides
Basic building blocks or sub-units of DNA and RNA consisting of a phosphate group, a base and five-carbon sugar.
Operator
A region found in an operon where a repressor is able to bind.
Operon
A cluster of adjacent structural genes in bacteria controlled by a single promoter and operating as a coordinated unit.
Osmosis
A specialised process of passive transport in which water molecules move across a partially permeable membrane from an area of high water (low solute) to an area of low water (high solute)
Peripheral proteins
Proteins that are anchored to the exterior of the plasma membrane through bonding with the lipids or integral proteins.
Phospholipids
Phospholipids major type of lipid found in plasma membranes and the main structural component of plasma membrane.
Plasma membrane
Partially permeable boundary of a cell controlling entry to and exit of substances from a cell
Post-transcription modification
Process occurring after transcription in which pre-mRNA is altered to become mature mRNA (splicing)
Primary structure
The specific linear sequence of amino acids in a protein
Prokaryotes
Any cells or organisms without a membrane-bound nucleus
Prokaryotic cells
Cells within prokaryotes that lack a membrane-bound nucleus
Promoter
Parts of the upstream flanking region of a gene where RNA polymerase binds, that contains base sequences termed a polypeptide.
Proteins
Macromolecules built of amino acid sub-units and linked by peptide bonds to form a chain, sometimes term a polypeptide
Proteome
The complete array of proteins produced by a single cell or an organisms in a particular environment
Proteomics
The study of the proteome, the complete array of proteins produced by an organism
Quaternary structure
The final level of protein structure in which multiple polypeptides join together o form a protein complex.
Random coiling
A type of secondary structure in proteins that does not fit in as either a alpha helix or beta-pleated sheet.
Redundant
see ‘degenerate’
Regulator genes
genes that produce proteins that control the activity of other genes
Ribonucleic acid (rna)
Nucleic acid consisting of a single chain of nucleotide sub-units that contain the sugar ribose and bases A, U, C and G
Ribosomal RNA (rRNA)
Stable form of RNA found in ribosomes
Ribosomes
Organelles that are major sites of protein production in cells in both eukaryotes and prokaryotes
RNA polymerase
an enzyme that controls the synthesis of an RNBA strands from DNA template during transcription
RNA processing
occurs after transcription and involves modifying pre-mRNA to form mature mRNA
Rough endoplasmic reticulum
Endoplasmic reticulum with ribosomes attached to
Secondary structure
a type of protein structure where three different folds of alpha helices, beta-pleated sheets and random coils can occur in amino acid chains, depending on the R groups in the different amino acids.
Semi-permeable
Allows only certain molecules to cross by diffusion
Simple diffusion
the movement of substances from a region of higher concentration to one of lower concentration of that substance; that is, down its concentration gradient.
Spliceosomes
complex molecules present in the nucleus that remove intron from pre-mRNA transcript
Structural genes
genes that produce proteins that contribute to the structure and functioning of an organism
TATA box
short base sequence consistently found in the upstream flanking region of the coding region of genes
Template strand
one strand of a DNA double helix that is used to produce a complementary mRNA strand during transcription
Tertiary Strand
the total irregular 3D folding of a protein held together by various bonds forming a complex shape .
Transcription
process of copying the genetic instructions present in DNA to messenger RNA
Transfer RNA (tRNA)
form of RNA that can attach to specific amino acids and carry them to a ribosome during translation.
Translation
process of decoding the genetic instructions in mRNA into a protein (polypeptide chain) built of amino acids.
trans-membrane proteins
proteins that are embedded within a span the plasma membrane, allowing them to have parts exposed to both the intracellular and extracellular environment.
Triplet code
the idea that a genetic code consists of triplets or three base-pairs.
trp operon
a collection of adjacent genes in bacteria that code for the enzymes needed in the production of tryptophan.
Universal
the property of the genetic code in which the code is essentially the same across all organisms
vesicles
membrane-bound sacs found within cell, such as secretory vesicles, which are involved in the export protein
Complementary
a molecule having a specific chemical structure that allows it to bond in a ‘lock-and-key’ fashion to another molecule.
