School of Medicine
University of Patras
>University of Patras
Undergraduate Courses

Biology I

Semester 1st ()

Code MED_111

Hours Lectures 3 hours, Laboratory work/tutorials/small group teaching 3 hours (per week)


Reading Material


  • Introduction to modern molecular and cellular biology.
  • Scientific methodology, ways ofbibliographic briefing, historical   examination of perceptions on the biological phenomena.
  • Cell theory.
  • Model organisms.

Biological macromolecules

  • Atoms - molecules and types of chemical bonds.
  • Chemical constitution of cells.
  • Emerging attributes of living matter.
  • Proteins Principles: from structure to operation. Protein function and regulation. Protein machines.  Homologous proteins. Protein Functional complementarity.


  • General characteristics. Microscopy.
  • Introduction to the morphology of the pre-and eukaryotic cells. Factors tha determine the cell size. Similarity and Diversity of the cells. Subcellular ultrastructure, cellular organelles-morphology, composition, functions.
  • Cell membrane. Structure, properties and function.
  • Cytoskeleton, intra-organization of the cell, proteinic fibrils: structure and function.
  • Membrane transfer, the carrier proteins and their function, membrane potential, electrochemical gradient, transport of substances by diffusion, passive and active transport, ion channels, maintaining osmotic balance in animal cells.
  • Intracellular transport, compartmentalization of the cell, membrane organelles as part of intramembranous system, sorting proteins - signaling sequences, chaperones, transport vesicles, protein secretion pathways - function of the Golgi apparatus as a sorting centre for exocytosis, the endosome as a sorting center for endocytosis, intracellular trafficking of substances, withdrawal of proteins.
    DNA as genetic material : structure and expression
  • Structure of DNA, structural and functional properties, its role as genetic material.
  • Structure of prokaryotic and eukaryotic gene, the role of individual structural / functional components of the genes.
  • Flow and expression of genetic information.
  • Replication, asymmetric replication fork, primosome and RNA primers, establishment and operation of the replicative machine, corrective action of the DNA polymerase.
  • Gene Transcription: Prokaryotic operons, eukaryotic genes, mechanisms / factors, changes of the original transcript, splicing and production of mature mRNA.
  • Genetic code. Translation of mRNA, structural and functional elements, mechanism.
  • Ribosomes.
  • Protein degradation.
  • Functional properties of RNA and its evolutionary history.

DNA damages, mutagens, reparation mechanisms, mutations

  • Primary lesions of the structure of DNA, mutagens, radiation, chemical mutagens, types of damage.
  • Mechanisms of reparation, interdependence between damage and  mechanism, generation of mutations, molecular nature of mutations
    The chromosomes and the regulation of gene expression
  • Structure, morphology, condensation and functional independence of eukaryotic chromosomes.
  • Meanings chromatin, euchromatin, heterochromatin.
  • Telomerase’s role. 
  • Organization of the chromosomes in the nucleus, human chromosomes.
  • Chromosomes and regulatory mechanisms of gene expression.
  • Molecular model of eukaryotic cell.
  • Differential expression of genes. 
  • Activators/suppressors, regulatory elements. Transcription factors.
  • Nucleosomes.
  • Modifications of histones, histone code.
  • Molecular switches.
  • Cellular specialization.
  • Epigenetics and regulation.
  • Cellular “memory”.

Cellular communication

  • General principles of cellular signalling.
  • Endocrine, paracrine, autocrine and neuronal signalling with their characteristics.
  • Types of receptors and signal sequences with their characteristics.
  • G-proteins, cAMP pathways, phospholipase C, activation of protein Ras.
  • Role of Ca ions in signalling.
  • Calmodulin and CaM kinases.

Cell division 

  • Process and mechanisms of cell division.
  • Phases of mitosis, cytokinesis, anaphase promoting complex, cohesins.
  • Meiosis: biological importance, differences of mitosis-meiosis.

Nondisjunction phenomenon and Aneuploidy.

  • Cell cycle and phases.
  • The central control system of cell cycle - cyclin-dependent kinases- inhibitors. Points of control. Response in DNA damage - the role of p53.


  1. Characteristics of life. Organization, regulation, evolutionary adaptation, response in the environment, growth, reproduction.  Evolution: Diversity and common characteristics. Emerging/new attributes: structural/functional relations between individual components concerning the level of complexity of organization of living matter. Studying levels of biological systems. Interaction between organisms and environment. Relationship between biological systems’ structure and their function.  Cell theory. Structural and functional unit of organisms. Perpetuation of life, homogeneity, diversity and evolution.
  2. Chemical bonds and their importance in the molecules and macromolecules of the cell: Covalent bonds, polar, ionic bonds, hydrogen bonds, hydrophobic and van der Waals interactions, carbohydrates, nucleic acids and proteins. Molecules of energy transportation (ATP, GTP, NADH, FADH and Acetyl-CoA). Mitochondria and energy in the cells.
  3. Comparison between DNA replication and transcription: The localization of resemblances and differences between the two operations that use the DNA as a template, to produce new molecules, in order to serve the aims of heredity (via cell cycle) the correction of DNA (via corrective replication) and the expression of genetic material (via transcription). The comparison is being made while considering the process and pre-requisite, the part of genotype which is involved and the result of the two functions.
  4. Structural and functional characteristics of genes. The role and the development of nucleic acids, the flow and the processing of genetic information and all the checkpoints from the nucleus to the cytoplasm. Regulation of gene expression - molecular mechanisms - factors - regulating elements. Genes and environment. Epigenetic regulation of gene expression.
  5. Cell membrane: The presence and operation of the cellular membrane structures within the eukaryotic cell. Methods of studying the structure and properties. Pathological phenotypes due to dysfunction of cell membrane.
  6. Cell signalling: a review of the relevant course syllabus, discussion of signalling mechanisms and their importance in the physiology of the cell and organism.
  7. Cell cycle:  Aim of the tutorial is the comprehension of the mechanisms that ensures the normal course and regulation of cell cycle and the importance of those mechanisms have for the genomic stability, the survival of cell and organism. The discussion is organized around two clinical examples: the chromosomal instability that cancer cells have and the use of medicine Paclitaxel (Taxol) in the treatment of cancer.


  1. Microscope – cell fractionation: Use of photonic microscope. Preparation and observation of samples from plant cells. Preparation and observation of samples of cells from mucosa of the tongue of each student. Nucleus isolation from mouse liver cells, pigmentation and observation in photonic microscope. Observation of ready cell samples.
  2. Cell development: Experimental approach to cell development of prokaryotic and eukaryotic cells. Cell development curve, mass spectrophotometric determination of prokaryotic cells’ mass, coated plates in sterile conditions and determination of concentration of live cells. Eukaryotic cell culture, media, culture conditions, observation of live cancer cells under the microscope, distinction between mitotic, interphase and dead cells.
  3. DNA isolation from epithelial cells. Each student isolates his DNA from dead epithelial cells, by washing out his mouth with sterile saline and observes the DNA after agarose gel electrophoresis.

Teaching in groups

Mutations - Reparative mechanisms of DNA: The meaning of mutation. Discrimination between hereditary and not mutations (germline and somatic mutations). Discrimination between mutations that concern numerical and structural changes of chromosomes and mutations that they concern changes of the genes. Mutations due to damage of the DNA. Which damages occur and which factors are responsible. The frequency of damage. What is induced mutagenicity. The mechanism of action of endogenous and exogenous factors causing mutations. Main reparation mechanisms of DNA and which type of repair each one makes. What are thymine dimers, how are they being caused and how are they being repaired. Important enzymes in DNA repair mechanisms and their targets. Human diseases are connected with DNA damage and DNA repair mechanisms.  The importance of these mechanisms for the stability but also the plasticity of DNA and the maintenance of species.