Metabolism in the 1800s

• Mahias Jakob Schleiden (1839), Theodor Schwann (1847) introduce cell theory; all organism composed of cells and their products; believed that cells could crystalize from non living maer. • Rudolf Virchow (1857): all cells come from preexisng cells. • Claude Bernard introduced the idea of homeostasis where organism maintain a steady state inside the cell. Sanctorius Sanctorius 1561–1636. Italian physician, physiologist

30 year experiment. Weighed himself, and all that he drank and ate. Weighed his faeces and his urine. - For every 8 pounds he ingested he excreted only 3 pounds waste. - Concluded that much of what is ingested is lost in perspiraon. Biological Producvity Rate of generaon of biomass. Primary producvity–photosynthesis. Secondary/terary producvity: consumpon Primary producvity

• Solar energy converted into reducing power (NADPH) (synthesize sugars, etc) and phosphate bonds (ATP) which can be used to power reacons locally. Early history

• Aristotle: plants need food and get it independently of animals. The reverse not the case. • Theophrastus: plants feed through their roots. Jan Baptist van Helmont

Flemish 1580 to 1644.

Chemist, physiologist, physician

• Planted a willow in a pot of known amount of soil. • Let the tree grow, weighing the water he applied and the tree’s growth. • Assumed plant growth came from water. Stephen Hales 1677—1761. English botanist, chemist, physiologist, clergyman

Careful studies on transpiraon Charles Bonnet, 1720 to 1793. Swiss naturalist Joseph Priestley 1733 to 1804. English theologian, chemist, philosopher

Discoverer of O2. 1774.

Focused sunlight on Mercuric Oxide using a magnifying lens: Trapped the gas that resulted as dephlogiscated air.

Antoine Lavoisier. 1743 to 1794. French Chemist • Mixed O2 and H2 and created H20 (using electric spark to start the reacon) • His quantave calculaons allowed him to recognized that water was not a pure element but resulted from the combinaon of Hydrogen and Oxygen. • Disproved phlogiston “La respiraon est donc une combuson.”

• With help of Laplace, designed a calorimeter. • Using guinea pig as an experimental animal; collected the carbon dioxide released. • Recognized respiraon as a slow combuson. • Showed others the way to study these phenomena. Jan Ingenhousz 1730 to 1799. Dutch Biologist, chemist, physiologist.

Plants: give off O2 in light. give off CO2 in dark.

More O2 given off than CO2.

Concluded that some of mass of plants comes from air. Nicolas-Théodore de Saussure. 1767 to 1845. Swiss chemist, plant physiologist What does human producvity refer to? • Secondary or terary producvity is always net consumpon. Respiraon

• Uptake of O2 and release of carbon dioxide in Biological systems. • Bond energy in O2 captured in NADH and ATP; short chain C-compounds used to make larger molecules. • Originally linked to fire. By early 1800

• “Organic” molecules. Many thought specific to life and connected with a vital force. • Increasingly though, experiments showed these to be composed of smaller elements in strict proporons. • Photosynthesis and respiraon increasingly seen to be principle metabolic funcons in living things. “Modern” concepon of metabolism

• A collecon of reacons that allow for material exchange between organisms and their environment. • Early concepons were oen vitalisc and interpreted the process as involving a life force. • “Stoffweschel” of early 19 century German physiologists. Mahias Jakob Schleiden. 1804 to 1881. Botanist • Microscopic studies showed that plants were composed of cells. • Cell Theory. • Later, a convert to Darwin’s new theory.

Theodor Schwann 1810 -1882. German physiologist Worked with Schleiden to develop cell theory. Cells come from other cells.

Schwann argued that yeasts were living and were responsible for fermentaon. Pasteur would later add to this work and confirm it experimentally. Claude Bernard. 1813 to 1878. French Physiologist.

Made extensive use of vivisecon in his studies.

“Mileu interieure”: The living body needs the surrounding environment and yet acts as though it were somewhat independent of it.

Human Ecology. The value of land

• Ricardo (1772 to 1823) English economist. • The ferlity of soils is God given; famines arise when farmers start to culvate more and more marginal soils, geng less and less in return. Thomas Robert Malthus 1766 to 1834. English cleric. Malthus proposes:

• Human populaon grows exponenal whereas their food supply grows only arithmecally. • Thus populaon will eventually reach a maximum capacity beyond which it exceeds its food supply. • Human inequality is the result of moral failure on the part of the poor William Godwin. 1756 to 1836. English Polical philosopher, reformer. James Anderson. 1739 to 1808. Scosh agricultural economist. • The relave ferlity of soils were historically determined and therefore depended on the nature of the relaonship of man to the soil. • Maintenance of land required raonal sustainable pracces. Anderson 1801. A calm Invesgaon of the circumstances that have led to the present scarcity of grain in Britain.

• Analysed crop ferlity. • Recognized division of town and country a significant factor: manure that would have stayed in the country moved into the city; nutrient lost to soils. • In addion, the Thames polluted by human excrement. Jusce von Liebig. 1803 to 1873. German Chemist. Early 1800s in Europe and North America • Widespread and repeated famines due to crop failure. • Studied soil Chemistry: “Organic Chemistry in its Applicaon to Agriculture and Physiology” (1840). • Carbon not acquired from soils. • Minerals and nitrogen were soil derived Metabolism originally introduced by German physiologists in early 19th century. • “Stoffweschel’’: material exchange and transformaon within cells. • Later, Liebig, extended this to include interacon of organisms with their environment. Soil inferlity

• A historical phenomenon created by poor farming pracces (failure to look aer the soil) Karl Marx. 1818 to 1883, German Philosopher, economist, sociologist, etc.

Founder of sustainability theory.

Analysed Capitalist producon. Capital (3 volumes). Put human ecology/sociology into a materialist framework.

Man as an animal

• Man depends on nature to meet his physical needs. • Man must produce in order to subsist; human labour was a necessary metabolic exchange between man and nature. • Value came from raw materials and human labour. Federic Clements. 1874 to 1945. American plant ecologist. • Using lamarckian ideas, saw plants and animals as able to transform themselves • Saw the ecosystem as a superorganism. • Succession would inevitably return the ecosystem to a given form for the climate/ terrain. Arthur Tansley. 1871 to 1955. English botanist, ecologist • Studied transformed landscapes. • Criqued Clements’ interpretaon of succession and climax; crical of holism • A materialist he saw the ecosystem as the result of a complex interacon of organisms; recognized that such ecosystems could be destroyed American dustbowl, 1930s Eugene Odum. 1913 to 2002. American ecologist