From the cell to the APP organism

Organisms are living structures made up of cells that perform a number of functions, ultimately contributing to the production of new living beings. Here, we will focus on functions linked to the exchange of matter with the environment and the distribution of matter within the organism. For all these functions, the structures involved will be understood in the light of optimization by natural selection: in other words, the structures have been shaped in such a way that their functioning is optimal (notion of structure-function relationships), knowing the physico-chemical laws governing these phenomena. The contribution to the realization of functions will be addressed at different levels of integration (cell, tissue, organ, apparatus/system, organism). Its variations will be considered in different phylogenetic groups (including animals (vertebrates, arthropods, annelids, etc.), terrestrial plants and other groups) and according to different modes and environments of life (aerial/terrestrial/aquatic environments (freshwater, marine), organism size, etc.).

The program of this UE will be declined on :

• 6 3-hour tutoring sessions
• 6 x 3-hour practical sessions
• 2 Scientific conferences + control

In addition to the methodological and interpersonal skills objectives (acquisition of cross-disciplinary skills common to the entire APP life sciences degree), this UE focuses on mastery of the following concepts:

• Assembly of cells into tissues: cell types, extracellular matrices (wall, basal lamina), intercellular junctions (without detailing the molecules, which will be studied in "From cell to molecule");
• Primary plant tissues (meristems, epidermis, rhizodermis, endodermis, sclerenchyma/collenchyma/parenchyma, xylem, phloem) ;
• Main categories of animal tissue (connective, epithelial, nervous, muscular), with a focus on the organization of digestive/respiratory epithelia (ciliated/with microvilli/keratinized);
• Vegetative organs of land plants: stem, leaf, root, and their histology (primary tissues). Involvement of tissues in the functioning of these organs (photosynthesis, root absorption, exchanges with the environment, internal circulations). Driving the circulation of raw sap through variations in water potential. Active transport of sugars. Molecular aspects will not be covered.
• Main organs of the digestive, respiratory, circulatory and excretory systems of animals. Smooth muscles, connective tissue + epithelium Excretion/osmoregulation in different environments (balance of passive and active exchanges - molecular mechanisms of organ function will not be covered). Respiratory exchanges in different environments (main limiting constraint depending on the environment).
• Smooth/skeletal muscles and vertebrate skeleton: muscle, bone and cartilage tissue. Contribution to locomotion (opposing muscles, e.g. extensors/flexors). An example of terrestrial locomotion gait. Viscous braking, aerodynamics. Development of lift in relation to wing structure (lift, aerodynamics). Arthropod exoskeleton and articulated appendages. Hydroskeleton and musculature of Annelids. Size-related constraints on the carriage and locomotion of organisms (metabolic allometry, skeletal allometry, locomotion cost allometry).
• Blood circulation: heart (structure, large vessels, role of compartments), vessel types (arteries, veins, capillaries, histology and functional characteristics). Heart muscle, capillary exchange motor.

100% Continuous assessment