Life at a Cellular level Flashcards
What are cells?
Basic unit for living organisms
Why are cells small?
So they have larger ratios, can allow gases to be exchanged easily and can diffuse
What is a prokaryotic cell?
Bacteria
What is a eukaryotic cell?
Human cell
What do prokaryotic cells not contain?
Nuclei, mitochondria and membrane-bound structures
What do eukaryotic cells contain?
Nuclei and membrane-bound structures
What are stem cells?
Unspecialised cells that can differentiate into other cell types
What are cancer cells?
Cells that fail to respond to cell-cycle regulations and divide uncontrollably throughout the body
What is the 1st law of thermodynamics?
Energy can’t be created or destroyed
What is the 2nd law of thermodynamics?
Energy transformations increase entropy as heat is produced
What is a dynamic steady state?
Equilibrium can not be reached as the products in one pathway can be used in another. It is a Continuation state due to food supplying and waste removing. Entropy can be used to increase the order of other compounds.
What is metabolism?
The chemical process by living organisms that allows food to be broken down for tissue growth. It is a mix of anabolic and catabolic reactions.
What is an anabolic reaction?
Energy is required. Non-spotaneous. Delta G= +ve
What is a catabolic reaction?
Energy is released. Spontaneous. Delta G= -ve.
What happens to the energy released by catabolic reactions?
It is used up by anabolic reactions in oder to produce more ordered compounds
What is the function of free-energy carriers?
They couple anabolic and catabolic reactions using phosphate group transfers
What are examples of free-energy carriers?
ATP and ADP
Where are electron carriers used?
In redox reactions
What are examples of electron-carriers?
NAD, NADP and FAD
What is substrate level phosphorylation?
ATP is produced by the phosphate group of a phosphorylated compound being transferred to ADP
What is oxidative phosphorylation?
The process by which enzymes oxidise cells to release energy which is used to create ATP
What are the major elements?
O,H,C,N,Na,Cl,K,Ca,S,P
What do functional groups affect?
The way molecules interact with each other
What is configuration?
The fixed arrangement of arms in a molecule (Cis or Trans)
What is conformation?
The precise arrangement of atoms in a molecule (free rotation)
What are the chemical reactions that occur in living organisms?
Redox, hydrolysis/condensation, internal rearrangements, making/breaking C-C and group transfers
What is a protein?
Polymers of amino acid monomers joined together by peptide bonds
What is a nucleic acid?
Polymers of nucleotide monomers linked by phosphodiester bonds
What are polysaccharides?
Polymers of monosaccharides linked by glycosidic bonds
What are cell membranes made up of?
Phospholipids, which creates a phospholipid bilayer
What is a cytoskeleton?
Structure made up of microfilaments and microtubules
What is the function of a cytoskeleton?
Provides strength and allows for cell motility
What are H-bonds?
Bonds between the electronegative atom and an electropositive H atom
What type of molecules are water-soluble?
Molecules with H bonds
What type of H-bond is most favourable in water?
Water-solute
What does amphiphatic molecule?
A molecule that contains both hydrophobic and hydrophilic parts
What is an example of an amphiphatic molecule?
Phospholipid
What is pH?
A measure of proton concentration
What is a buffer?
Solutions of weak acids. Acids dissociate to acid-base pairs in solution.
How is pH kept constant?
Equilibriums maintaining Ka and Kw
What does a nucleus contain?
DNA, nucleoprotein and some RNA
What is a nucleolus?
Site for ribosomal RNA synthesis
What is the Endoplasmic Reticulum?
Interconnecting network of membranous tubules, vesicles and faltered sacs
What are the 2 types of Endoplasmic Reticulum?
Rough and Smooth
Why is the endoplasmic reticulum rough?
Ribosomes
What is the function of the rough endoplasmic reticulum?
Synthesis of packaged proteins
What is the function of smooth endoplasmic reticulum?
Membrane synthesis and repair
What is a ribosome?
Small organelle of 2 subunits that is used to create protein in cells
What is a Golgi apparatus?
Stack of flattened vesicles that are used to process secretary proteins and to synthesise polysaccharides
What is a lysosome?
Membrane bound organelles that act as cellular stomachs ad contain granular materials
What is a peroxisome?
Small membrane bound organelles that contain enzymes (oxidase and catalase)
What is a mitochondrion?
Mobile organelle that contains a permeable membrane made of porin and an inner folded membrane containing amorphous matrix
What is a flagellum?
Long organelle made up of microtubules that moves like a snake
What is a cilium?
Small organelle that is made up of microtubules that moves stiffly
