
<ul>
  <li>Transcription</li>
  <ul>
    <li>
      Begins with the binding of transcription factors to DNA within a promoter sequence (such as
      the TATA box)
    </li>
    <li>One strand of DNA forms a template for the synthesis of messenger RNA</li>
    <li>This is catalysed by RNA polymerase which binds to a DNA promoter region</li>
    <li>
      The process moves along the DNA strand as the RNA molecule is built in the 5&rsquo; to
      3&rsquo; direction
    </li>
    <li>The process stops when it meets the termination signal on the DNA molecule</li>
    <li>This transcript is an exact replica of the DNA strand</li>
    <li>The introns are excised and the exons spliced together at spliceosomes</li>
    <ul>
      <li>
        Some molecules undergo &lsquo;alternative&rsquo; splicing and thus form other active
        mRNA&nbsp;
      </li>
      <li>This is another mechanism of regulating gene expression</li>
      <li>Splicing occurs in the nucleus</li>
    </ul>
  </ul>
  <li>The mRNA molecule then leaves the nucleus</li>
  <li>NB: mRNA is monocistronic meaning it only encodes for one protein</li>
  <li>
    Its 5&rsquo; end is blocked by 7-methylguanine and a poly-adenine tail is added to the 3&rsquo;
    end which aids transport to the cytoplasm and provides stability
  </li>
  <li>Translation</li>
  <ul>
    <li>
      Performed by specific transfer RNA (tRNA) which is specific for an amino acid and transports
      them to the mRNA template on the ribosomes
    </li>
    <ul>
      <li>Only 1% of cellular RNA is mRNA</li>
    </ul>
    <li>
      Amino acids specific for the three nucleotide bases are attached by their C-terminal ends
    </li>
    <li>Each tRNA anticodon is linked with the matching codon on the mRNA</li>
    <li>
      The process is controlled by aminoacyl-tRNA synthetases which couples amino acids to the
      matching tRNA molecule and peptidyl transferase which uncouples tRNA from amino acids and
      joins it to the chain
    </li>
    <li>Translation is always initiated at a codon specifying methionine</li>
    <li>
      Initiation factor 2 (IF-2) catalyses the reaction between specific tRNA molecules and the mRNA
    </li>
    <li>The mRNA is read a codon at a time from the 5&rsquo; to 3&rsquo; direction</li>
    <li>The polypeptide chain is built from the N-terminal end to the C-terminal end</li>
    <li>
      The stop codon initiates release factor to bind the A site (this is where incoming tRNA
      molecules bind), blocking further tRNA and releasing the polypeptide into the cytoplasm
    </li>
    <li>The polypeptide chain can be further modified after translation</li>
  </ul>
</ul>


Genetics

Polypeptide Synthesis

Intro

FRCOphth Part 1 Study Notes

Orbit and ocular adnexae

Orbit

Extraocular Muscles

Orbital Blood Vessels

Paranasal Sinuses

Lacrimal Glands

Tear Film

Eyelids

Blinking

Anterior segment - ocular surface

Conjunctiva

Conjunctivitis

Sclera

Cornea

Corneal Structure And Development

Corneal Physiology

AC to Lens

Angle

Ciliary Body

Aqueous Humour Dynamics

Iris

Pupil

Lens

Posterior segment

Choroid

Vitreous

Retinal Macrostructure

Neurosensory Retina

Retinal Pigment Epithelium

Neuroanatomy

Venous Sinuses

Cerebral Ventricles

Cerebral Blood Supply

Supranuclear Gaze Pathways

Head And Neck Autonomic Nervous Supply

Head And Neck Glands

Osteology

Nerves

Muscles And Pharyngeal Arches

Extraocular Nerves

Sensory Nerves

Physiology

Physics Of Blood Flow

Neuronal Control Of Blood Vessels

Oxygen-Haemoglobin Dissociation Curve

Cytochrome p450

Pituitary Gland

Thyroid Hormone Production

Insulin

Glucagon

Parathyroid Hormone

Corticosteroids

Catecholamines

Cardiac Cycle

Renal Physiology

Fluid Balance

Acid-Base Balance

Muscle Physiology

Sensory Fibres

Cutaneous Receptors

Endocytosis

Glycosaminoglycans

Condensed Ocular Biochemistry

Eye Movements

Accomodation

Vision

Visual Cycle And Phototransuction

Visual Pathway

Visual Acuity

Colour Vision

Binocular Vision

Pathology

Collagen

Tissue Damage

Inflammation

Disease Entities

Wound Healing

Thrombosis / Atherosclerosis

Cell Growth

Neoplasia

Histopathology

Nystagmus

Free Radicals And Antioxidants

Immunology

Ocular Immunology

Microbiology

Viral Infections

Bacterial Infections

Fungal Infections

Protozoa

Nematodes

Antimicrobials

Chromosomes

Mitosis

Meiosis

Genes

Histones

MicroRNA

Hardy-Weinberg Equilibrium

Mutations

Chromosome Defects

Autosomal Inheritance

X-Linked Inheritance

Mitochondrial Inheritance

Multifactorial Inheritance