Eukaryotic and Prokaryotic Cells

TP1: Eukaryotic and Prokaryotic Cells

• The study of eukaryotic and prokaryotic cells begins with understanding their basic building blocks, starting from the subatomic level.
• The subatomic level comprises electrons, protons, and neutrons, which are the fundamental particles of an atom.
• The atomic level includes atoms like oxygen and iron, classified by their function: primary (carbon, phosphorus, hydrogen, oxygen, sulfur, forming cell structures like the membrane), and secondary (calcium, potassium, magnesium, chlorine, iodine, essential for cell function but not part of its structure).
• The molecular level involves the union of different atoms forming molecules like carbon dioxide, amino acids, carbohydrates, proteins, and lipids.
• These molecules can interact through various forces, forming monomers (glucose, alanine, adenine).
• Monomers unite to create polymers (lactose, dipeptides), which can aggregate to form macromolecules like proteins.
• The subcellular level is where these molecules are organised to form larger structures such as cell organelles
• Subcellular structure includes structures such as the cell membrane and the Golgi apparatus.
• The cellular level classifies cells as either eukaryotic or prokaryotic.

Eukaryotic Cell Substructures

• The eukaryotic cell's plasma membrane defines the cell's boundary, offering mechanical protection and acting as a semipermeable barrier.
• The cell membrane helps maintain a suitable internal environment
• The nucleus, enclosed by a nuclear membrane, stores genetic information.
• Within the nucleus, DNA replication, and RNA synthesis, processing, RNA and DNA repair occurs.

Ribosomes and Endoplasmic Reticulum

• Ribosomes synthesize proteins.
• There are both free ribosomes, and ribosomes attached to the Endoplasmic Reticulum
• The endoplasmic reticulum is involved in protein synthesis and processing, lipid synthesis (smooth ER), detoxification (smooth ER), and calcium storage (smooth ER).

Other Organelles and Cell Junctions

• The Golgi apparatus modifies, packages, and distributes proteins synthesized in the rough ER.
• Lysosomes handle cellular digestion.
• Peroxisomes detoxify cells and metabolize lipids.
• Mitochondria perform aerobic respiration and produce energy.
• Cell junctions connect cells through adhesion proteins, including occlusive junctions, adhesion junctions, and gap junctions, which facilitate communication.
• Adhesion junctions anchor cells to each other, while gap junctions enable cellular communication.

Cytoskeleton and Cell Types

• The cytoskeleton consists of microfilaments, microtubules, and intermediate filaments.
• The cytoskeleton helps shape cells and supports intracellular mechanisms
• Organisms are divided into autotrophs, which produce their own food, and heterotrophs, which consume other organisms.

TP2: Water

• Water comprises 60% of an adult male and 55% of an adult female body weight.
• Water comprises 80% in infants and 50% in the elderly.
• The content of water organ systems in young adults varies: kidney (>80%), lung (>80%), heart (79%), skeletal muscle (75%), skin (70%), bone (20%), adipose tissue (10%).
• In an adult male body water is split between intracellular (2/3, 28L) and extracellular (1/3, 14L) spaces, with the extracellular space divided into interstitial (10.5L) and intravascular (3.5L) fluids.

Molecular Structure and Polarity

• Water is a polar molecule due to uneven distribution of electron density, related to interactions through polar covalent bonds (where atoms share electrons) and hydrogen bonds (polar interaction between electropositive hydrogen and electronegative oxygen atoms).

Physical Properties

• Water has a high melting and boiling point and maintains a liquid phase between 0°C and 100°C.
• A high heat of vaporization is needed for a unit mass of water to turn from liquid to gas, useful for thermoregulation through sweat evaporation.
• Water's high specific heat means that large amount of energy is needed to increase temperature by 1°C.
• Water absorbs heat from metabolic reactions.
• Water has a high surface tension because it interacts with fewer molecules at the surface than within the liquid.
• Anomalous density variation includes expansion upon freezing.
• Hydrogen bonds in ice keep water molecules separated.
• The increase in water density occurs upon rising temperature between 0° and 4°C.

Water As A Solvent

• Water is described as the universal solvent
• It can form solutions with polar compounds and dissolves stable hydrophilic, lipophobic substances.
• Nonpolar compounds do not interact with water and are therefore insoluble.

Additional Concepts

• Permeable means something can pass through
• Impermeable means nothing can pass through
• The concept of pH involves measuring the acidity or alkalinity of a solution and acknowledging the equilibrium between protons and hydroxyls. Buffers stabilize pH.
• Osmosis: is the net water flow across a semipermeable membrane from an area of lower to higher solute concentration.
• Tonicity:refers to the permeability and osmolarity properties of a cell membrane
• Osmolarity: Refers to number of particles in a solution
• Difusion describes the movment of ions in favour of greater concentration.

TP3: Biological Building Blocks

• Biomolecules consist of lipids, carbohydrates, proteins, and nucleic acids.
• All organic molecules are composed of carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur (CHONPS).
• The chemistry of life revolves around carbon due to its tetravalent capabilities.
• Carbon forms covalent bonds, and generates isomers, it creates long chains, and different positions from functional groups.
• The monomers are monosaccharides, amino acids, nucleotides, and fatty acids.
• The polymers are polysaccharides, proteins, and nucleic acids.
• Macromolecules are polymers organized to weigh over 5000 Da.

Carbohydrates and Lipids

• Carbohydrates: are chains of monosaccharides that are linked by O-glycosidic bonds often weighing >5000 Da
• Carbohydrates can be homopolysaccharides or heteropolysaccharides, and linear or branched.
• Carbohydrates are reserved for for energy and can be glycogen or amylose and are structure like cellulose or cutina
• Lipids :are low molecular weight with molecular Polymorphism between 750-1500 Da

Structure and Groups

• Polymers are just organized monomers
• Macromolecules are organized polymers that weight <500 Da
• A few funtional groups are - hydroxyl,-carbonyl,-carboxyl,-ester,-amino,-ion phosphate

Most Frequent Links

• Ester links, which form between carboxylic acids and alcohols.
• Amide links, which form between carboxylic acids and amines.

Monosaccharides

• It consists of simple sugars or carbohydrates, which are hydrides of carbon.
• The formula is CnH2nOn.
• They make up linear chains of 3-7 carbon atoms linked by simple bonds.
• Each carbon has a –OH group except one, which has a double bond with an oxygen atom, yielding the carbonyl group.
• If the carbonyl group is at the end of the chain, it is an aldehyde. Otherwise, it is a ketone.
• They can be polyhydroxyaldehydes or polyhydroxyketones of 3-7 carbon atoms.

Classification based on carbon

• Trioses
• Tetroses
• Pentoses
• Hexoses
• Heptoses
• Functional group:
• Aldoses
• Ketoses
• Despolarization:
• Dextrogiro (D) deflects light to the right
• Levogiro (L): deflects light to the left

Principal Monosaccharides

• Trioses (C3H6O3) are the main metabolic intermediaries.
• Pentoses (C5H10O5) are components of adenosine triphosphate and ribonucleic acid.
• Hexoses (C6H12O6) include glucose and fructose (metabolic fuels) and galactose (part of lactose).

Cyclic Structure of Monosaccharides

• Monosaccharides with 5+ C adopt a cyclic form in aqeuous solution
• Anomeric Carbon: New asymmetric element
• ɑ -OH : anomeric element sits under any ring
• ɑ -OH: sits above arry ring

Properties of Monosaccharides

• Physical
• Solid cyrstals
• Soluable in water
• White
• Sweer
• Chemical: They can oxidise, and able to reduce when an element is joined to them
• Formed from Amino sugars, Phosphorus sugars and desoxy sugars
• They unite with glycosidic O, which forms covalent links as a result of -OH

Polimers

Oligosaccharides: links O glycosides

• 2 to 10 monomers

• Most noteable: dissacharides

• Disaccharides: Most noteable:

• Maltose

• Lactose

• Saccharose

Glyoscdic Links properties

• They form through Dehydration
• They are broken apart in hydrolysis

TP4: Bioenergetics and Enzymatic Kinetics

• Bioenergetics and enzymatic kinetics study the transduction and transformation of energy.
• Cellular activities operate together to get chemical energy, polymerize precursors, and synthesize and degrade biomolecules.

Thermodynamics

• The first law of thermodynamics states that energy is conserved.
• The second law says that in an open system disorder is favored

Important equations

• Enthropy = disorder
• Enthalpy = Heat content
• Gibbs free energy = Amount of energy availible to do work

More Equations

∆ = a reaction w/ constant temp &pressure constant

• ∆G negative: exergonic, spontaneous
• ∆G positive: endergonic, non-spontaneous
• ∆G = 0: reaction is at equilibrum
• ∆G = ΔH − T ΔS, (∆G = changes in free energy (joules/mol , ∆H = enthalpy (joules/mol), T = temperature (K), and ∆S = entropy (joules/mol K)

Graphics of Bioenergetics

• Eje Y:Gibbs free energy
• Eje X: Reaction progress

Reaction Coupling and Kinetics

• Reactions are coupled to make them thermodynamically spontanopus
• Ex: Glucose+Pi → Glucose-6P+H20
• ATP+H20 → ADP+Pi
• Enzymatic kinetics studies reaction speed & the factors that infulence based on concentration and substrait.
• Enzyme are catalisers with protenic nature.

enzyme characteristics

• Acts in the correct temp and ph
• Sometimes needs cofactor
• Highly especific properties to substrait
• Capacity to Speed up chemical reactions
• Enzymes can be 100% proteic or not
• Cofactors are things Enzymes use

Enzyme Actions

• Can be Competitive, non competitive,or suicide (Enzs link w/links)

Enzime Regulation Forms

• Allosteric
  • covalent
• Activating proteins
• Uniting Prot, regulating, compartimentalization

Tp5: Geneatic Mechanism

• Deoxirribonucleic Acid replication: in a way DNA is able to replicate

Properties:

Semiconservative: the DNA splits and combines to be used later Bidriectionality: DNA forms a sort of open bubble Semidiscontinuation: the form is discontinued

How RNA splits

RNA goes against the direction

Replication Process and Enzimatic actions

• Polimerisation: enzimes such as helicases, primases, ligases etc are emplyed
• Types of RNA polimerases: the are needed and used in mitosis
• Terminators are the action that the cell enacts with the polimerazation, acting acordingly
• DNA polimerazation can be avoided under the light
  • there is also:
  • replication of DNA

Chromosoms, and RNA

• Codons and Chromosoms action, by reading the m RNA
• The genetic code:
• Each amino acid codon has a meaning, by coding
• The types: aminoacid, and protein type and codification

TP6: Genetic Mechanisms

• Bases : The difference between dna and RNA nitrogenous
• The sugar: the difference between the chains
• Location in the cell: The type and location
• It gives us a way to measure: The chemical and molecular structure of the water
  • 0 is the standard mesure, < 0 is more acidid and > is more alcaline.
• H = -log ( H+)

RNA types and functions

• RNAm: Total cellular portion that transfers genetic information from DNA to ribosomes.
• They act as molds that serve to specify the sequence of aa of the chains polypeptide.
• RNA: Adapter Molecule
• They bend over each other by self-complementation of bases.
• The aa is carried to its place of union with others covalently t o the aa:
• RNAr:
• It forms major and minor subunits which creates peptide links
• Form subunits greater and lesser. in eukaryotes 50s and 30s. in prokaryotes 60s and 40s

Transcription

Passage of information from the DNA molecule that serves as a mold to the RNA molecule thyrough the complementarity of bases. 1. It needs templates 2. it always reads and goes opposite

TP7:

-Membrane lipids are amphibathic molecules that assemble and seal. • It's a lipid the main component. Phospholipids main components of membrane.

• Because its parts can easily move it has characteristic fluid is made with the dynamic. And the sugars are an important thing for this fluid structure

Distribution by membrane style:

• Outwards components
• Intern comonents . -phosphaltiserina etc

It does a few things like

• Lateral dífution,rotation and flip flops
• The flip flop is catalyz by FLIPASA.
  • fluid membrane is dependent on conoentration ,and temps, oscillating between jelly like and fluid stage.

factors

• Aummenting tempo -> fluidid • Reduce cola -> Fluidid

So to keep perfect balance, it needs the same temo as outer side, and be as open as closed

Transport

• Integration and CO2
• hidro and bensine
• urea
• gicose
• K MG NA

###TP14: Cell division Mechanisms

• It describes celular and molecular changes that occur, such as: • Nuclear envelope break down

• It also goes over Mitosis (cell replication) and Meiosis and their importance

Mitosis proccess:

1.. Interfase: cell is ready for division and chromosome is fully replicatied 2.. Prophase: chromosomes prepare 3.. Metaphase: chromosomes align 4.. Anaphase: replicated chromosomes is split and new cells start 5.. Telophase: division is completeted

Meiosis is is pretty identical but there are two of these divisions resulting into 4.