LQB186 Human Cell and Molecular Biology Flashcards

Flashcards for LQB186 Human Cell and Molecular Biology exam review.

__ contain two or more elements joined together.

Molecules contain two or more elements joined together through chemical bonds. These can be either the same element (like O2) or different elements (like H2O).

__ are molecules made up of different elements, e.g., carbon dioxide (CO2).

Molecules made up of different elements, e.g., carbon dioxide (CO2).

Elements are __ into compounds and molecules via strong bonds where electrons are shared evenly (covalent) or not shared evenly (ionic).

Held together into compounds and molecules via strong bonds where electrons are shared evenly (covalent) or not shared evenly (ionic).

structures = alpha helix and beta pleated sheet, formed by .

Alpha helix and beta-pleated sheet, formed by hydrogen bonding.

structure = .

Sequence of amino acids.

The seven different functions of are .

Structural, storage, transport, communication, movement, enzymatic, or toxic (defence).

The general formula of a carbohydrate is __.

(CH2O)n where n = any number from 3 to 7.

An omega-3 v an omega-6 is remembered by __.

Position of first double (unsaturated) bond in hydrocarbon chain starting at the methyl (CH3) group.

__ are particularly important to the formation of the cellular membranes - phospholipid bilayers.

Phospholipids.

Phospholipid bilayer cell membranes are __.

Semi-permeable.

Osmosis is __.

The passage of water.

All cells have __.

Plasma (cell) membrane, cytoplasm (cytosol + cytoskeleton), chromosomes, ribosomes.

__ is the powerhouse of the cell.

Mitochondria.

Genomic DNA in prokaryotes is __ .

Double stranded.

Genomic DNA in eukaryotes is __ .

Linear chromosomes

__ occurs when the cell brings in macromolecules by forming new vesicles by invagination of plasma membrane.

Cell brings in macromolecules by forming new vesicles by invagination of plasma membrane.

__ occurs when the cell engulfs large particles – including entire organisms.

Cell engulfs large particles – including entire organisms.

The extracellular matrix __.

Supports the cell from the outside and is connected by special proteins (integrins) that span across the plasma membrane to the cytoskeleton of the cell.

ECM components include __.

Collagen, elastin, and fibrillin.

__ is energy in a system that can perform work when temperature and pressure are uniform.

Energy in a system that can perform work when temperature and pressure are uniform.

-∆G = __.

-∆G = system is unstable and energy is released, reaction is spontaneous, exergonic.

+∆G = __ .

+∆G = system required input of energy, reaction is not spontaneous, endergonic.

Enzymes __.

Lower the energy of activation.

Induced fit theory says that __.

Binding of substrate to enzymes causes a conformational (shape) change that enhances its ability to catalyse a chemical reaction.

Competitive inhibitors bind the __.

Active site.

Noncompetitive inhibitors bind the __.

Allosteric site.

Feedback inhibition is when __.

A product of the reaction inhibits an enzyme early in a pathway.

Microfilaments are made from the protein __.

Actin.

Largest (25 nm diameter) of the cytoskeleton fibres are __ .

Microtubules.

Motor proteins are __.

Kinesins and dyneins.

Cytoskeleton fibres __.

Maintain cell shape, protect the cell, enable motion, intracellular transport, and are important for cell division.

In flagella and cilia __.

Outer doublets are connected by dynein motor proteins.

Ribose sugars in DNA and RNA __.

Govern the 5’ to 3’ direction.

The direction in DNA and RNA is __.

5’ to 3’

The purines in DNA are __.

Adenine and guanine.

The pyrimidines in DNA are __.

Cytosine and thymine.

Carrier proteins include __.

Uniport, symport, and antiport.

__ on the surface of cells act as identity tags.

Glycoproteins.

Proteins of the ECM are attached to the proteins of the cytoskeleton via __.

Integrins.

Histones are full of __ that carry a positive charge.

Basic amino acids.

DNA is wrapped around histone proteins forming a __.

Nucleosome.

Transcription is regulated by a promoter sequence that binds proteins called __.

Transcription factors.

__ removes the introns.

Spliceosome.

__ in some mRNAs will interact with the 18S structural rRNA to help orient the start codon into the P site of the ribosome.

Kozak sequence.

Amino acids are added to the 3’ end by special enzymes called __.

Aminoacyl-tRNA synthetases.

__ was introduced as a fifth nucleotide.

Inosine

Translation has three steps __.

Initiation, elongation, and termination

Proteins with a signal sequence are made into the __.

RER lumen

__ recognizes the initial combination of amino acids for the RER.

Signal recognition particle.

__ played an important role in the evolution of our genome.

Exon shuffling.

Post-translational modifications include __.

Glycosylation, lipidation, and ubiquitination

DNA is replicated in a __ manner .

Semi-conservative.

__ sit at the replication fork to separate the strands.

Helicases.

The lagging strand needs to be copied in pieces in __.

Okazaki fragments.

__ joins the Okazaki fragments together.

DNA ligase.

To prevent important information being lost the ends of chromosomes contain __.

Telomeres.

Checkpoints are all controlled by the interaction of __ waiting inactive until the cell makes enough new cyclin protein to bind to the CDK to activate it.

Cyclin dependent kinases

G1, S and G2 phases are all phases of __.

Interphase.

Gametes are __ meaning they only have one set of each of the chromosomes.

Haploid.

__ is the first way for sexual reproduction to allow diversity.

Crossing over.

__ is the second way of generating genetic diversity because the way the chromosomes are separated is independent of each other.

Independent assortment.

Types of mutations include substitutions, deletions, insertions, ___, __.

Nonsense, silent

On a chromosome map __ means translocation.

t = translocation

On a chromosome map __ means inversion.

inv = inversion

Cloning tools are __.

Plasmids, restriction enzymes and ligase.

__ cuts DNA at a specific site = combination of bases, often a palindrome (same sequence in opposite directions, and complementary on the two strands).

Restriction enzymes

__ repairs the sugar phosphate backbone so can joins cut pieces of DNA back together.

Ligase

NADH takes the electrons to the __ in the inner folded membrane.

Electron transport chain

A single ligand binding a single receptor can result in a big response in the cell - this is called __ of the signal.

Amplification

Caspases are key enzymes = initiator and executioner in __.

Apoptosis