The chromosomes of each gamete introduce hereditary material into the new cell. This material controls the development and characteristics of the embryo, such as the characteristics of the adult organism. Because the hereditary material comes from the parents, the new generation is similar to the parents in some ways, but different from both in others. This new generation has all the characteristics of its species, but it also has its own individual characteristics that distinguish it from all other individuals of that species. Heredity is the branch of biology that deals with the ways in which hereditary information is passed from parents to the next generation. Modern heredity began in the nineteenth century with the scientific work of the Austrian priest Mendel.
The idea that cells are living entities and that plants are aggregates of cells can be attributed to various scientists who contributed to the development of cell theory. One of the key figures associated with this concept is Theodor Schwann. Theodor Schwann, a German physiologist, and zoologist, collaborated with botanist Matthias Schleiden in the 19th century to formulate the cell theory. In this theory, they proposed that cells are the fundamental units of life, and all living organisms are composed of cells. Schwann specifically focused on animal cells and their role in living organisms. Matthias Schleiden extended this concept to plant cells, suggesting that plants are also composed of cells.
Together, Schwann and Schleiden’s work laid the foundation for modern cell biology, emphasizing the significance of cells as the basic building blocks of life. Their contributions are pivotal in understanding that both animals and plants consist of cells, supporting the idea that cells are indeed living entities and that plants are aggregates of these living cell units.
Who is Theodor Schwann?
Theodor Schwann (lived December 7, 1810 – January 11, 1882, born in Cologne, German zoologist who founded modern histology by defining the cell as the basic unit of animal structure)
After studying medicine in Berlin, Schwann assisted the physiologist Johannes Peter Müller (1834-1838). In 1836, during his studies, he studied the digestive processes in the stomach, identified an important substance for digestion and named it pepsin, and developed the first enzyme prepared from animal tissue. At the Catholic University of Leuven (Louvain), where he received the title of professor (1839-1848), he observed the formation of yeast spores and concluded that the fermentation of sugar and starch was the result of life processes. He knew mathematics well and started working at the University of Jena, a year later, Theodor Schwann discovered that all animal tissues are composed of cells (1839), his microscopic research on their structure and growth lasted for many years, too long for animals.
In 1839, the German zoologist Theodor Schwann produced a detailed report on the cellular basis of animal life. Schwann concluded that animal and plant cells had essentially the same structure and expressed his cell theory as follows: All organisms are composed of one or more cells.
The idea that cells are living entities and that plants are aggregates of cells is often attributed to Matthias Schleiden and Theodor Schwann, who were 19th-century scientists and pioneers in the field of cell biology. This concept is a fundamental principle of cell theory, which they developed.
Matthias Schleiden was a German botanist who, in 1838, proposed that all plant tissues are composed of cells and that cells are the basic units of plant structure. Theodor Schwann, a German physiologist, extended this idea to animals in 1839, suggesting that cells are also the fundamental units of animal tissues. Together, their work laid the foundation for the modern understanding of cells as the building blocks of living organisms.
So, it was Schleiden and Schwann who speculated that cells are living entities and that plants, as well as animals, are composed of cells. This marked a significant advancement in our understanding of biology and laid the groundwork for the development of cell biology as a scientific discipline.