Cellular Metabolism and Biodiversity: From Molecules to Ecosystems

Catabolic and Anabolic Metabolism

Catabolic metabolism is oxidized when it loses electrons. It is a set of molecular processes that transform complex molecules into simpler ones. The energy molecule ATP stores energy. Energy is released during the oxidation of molecules, especially if O₂ is the ultimate acceptor (aerobic) or if another acceptor is used (anaerobic). Fermentation is the incomplete oxidation of energy molecules. For example, glucose activates Bacillus, and the initial product in the muscles is lactic acid. Alcohol fermentation starts with glucose in yeast, and the final product is ethyl alcohol. Putrefaction of proteins into simpler molecules is performed by some organisms.

Anabolism is a set of reduction reactions in which it is necessary to transform simple molecules into energetically complex ones. Anabolism can be heterotrophic or autotrophic. Autotrophic anabolism can be photosynthesis or chemosynthesis.

Meiotic Prophase I

During meiotic prophase I, the chromatin condenses, and chromosomes are displayed. The nuclear membrane disappears, and tetrads are distinguished. The chromatids are tightly together, and there is an exchange of genetic material between chromatids at chiasmata.

Levels of Organization

Atoms, macromolecules, inorganic and organic molecules, organelles, tissues, cells, systems, devices, individuals, species, populations, communities, and ecosystems.

Taxonomy

A species is made up of all individuals with similar structural and functional characteristics, which have a common ancestry and originate among them a fertile heritage. The taxonomic hierarchy is: Phylum, Kingdom, Class, Order, Family, Genus, Species.

The five kingdoms are: Monera, Protoctista, Animalia, Fungi, Plantae.

Cellular Organization

• Unicellular: A single cell, e.g., bacteria.
• Colonial: A group of cells in an aqueous medium.
• Multicellular: Many cells that are not all alike as a result of differentiation and specialization. They share the work and are grouped into tissues. The cell maintains basal metabolic functions, and there is coordination and integration of each cell's contributions.

Diversity of Life

Monera

Cocci, curved bacilli, bacteria (eubacteria, archaebacteria).

Protoctista

Protozoa, heterotrophic, flagellates, ciliates, sarcodina (pseudopods), sporozoa, unicellular and pluricellular algae (diatoms, green, brown, red).

Fungi

Mycelium, septate hyphae, zygomycetes (e.g., Penicillium), ascomycetes (mycelium, septate hyphae), fungi + algae (lichens), basidiomycetes (basidia, septate hyphae).

Plants

Moss (thallus), bryophytes, tracheophytes or cormophytes, pteridophytes (ferns), spermatophytes (colorful flowers), gymnosperms (not showy), angiosperms (monocotyledons, dicotyledons).

Animals

Mammals, cnidarians (choanocytes, e.g., medusa, coral, polyp), platyhelminthes, nematodes, annelids, mollusks (lamellibranchs, gastropods, cephalopods), arthropods (arachnids, e.g., spiders, scorpions, mites), crustaceans, myriapods, insects, echinoderms, chordates (vertebrates, e.g., fish, amphibians, reptiles, birds, mammals).

Biodiversity and Conservation

Benefits of Biodiversity

• Ecological
• Economic
• Ethical
• Aesthetic

Threats to Biodiversity

• Habitat loss
• Pollution
• Overexploitation
• Introduction of new species
• Destruction of ecosystems

Endemic Iberian Animals

Iberian lynx, Iberian ibex, wolf, grizzly bear, giant lizard, black vulture, Balearic shearwater, Spanish imperial eagle, Manzanilla, Cazorla violet.

Plant Growth

Plant growth occurs in meristems. Primary meristems are responsible for growth in length. Secondary meristems are responsible for growth in length and thickness. They are made up of embryonic cells that remain in adult plants. The cambium is the innermost layer and increases thickness. The phellogen is the outermost layer and is more protective.

Plant Tissues

• Fundamental parenchyma: Aquifer (reserve), chlorophyll, aeriferous.
• Conducting tissues: Collenchyma, sclerenchyma, xylem (vessels), phloem (sieve tubes).
• Protective tissues: Corky (lenticels, suberin).
• Secretory tissues: Epidermal (leaf petiole, epidermis, cutin, upper beam, underside, limbus).
• Palisade parenchyma: Vessels, conducting stoma, ostiole, lagoon, substomatic chamber.