By Chet Yarbrough
Biology: The Science of Life
By: The Great Courses
Lecturer: Stephen Nowicki
Stephen Nowicki (Professor of Biology at Duke University.)
Professor Stephen Nowicki offers a 36.5-hour lecture on Biology. From the origin and growth of life to the chemical and neuronal function of living things, Nowicki systematically reveals experimentally tested knowledge of the “…Science of Life”. This brief review only addresses a few of the many fascinating details Nowicki explains.
Nowicki suggests, cells evolve from the agglomeration of detritus from the “Big Bang”.
The early formation of these cells is missing two ingredients for life. Nowicki explains these early cells evolve from violent volcanic and electrical activity of the “Big Bang”, an environment in which those two missing ingredients are created.
Nowicki explains early non-living cells are bombarded by electrical storms that generate amino acids (organic compounds) and sugar from violent atmospheric conditions that include water.
In the early 1950s, these conditions were tested in laboratory conditions and found to create two essential building blocks of life. Nowicki explains, these building blocks (amino acids and sugars) became part of non-living cells.
The eukaryotic cells had a nucleus containing genetic material while prokaryotic cells carried free-floating genetic material without a nucleus. Nowicki then explains the role nucleotides (protein) play in activating genetic material within these cells.
Nowicki notes DNA is present in both prokaryotic and eukaryotic cells, but they need to have a way of being activated. With replication, molecules (chemical compounds) could form. Nowicki explains living matter originated from the clumping and replication of these molecules.
Nowicki explains ribonucleotides (proteins) were created in the primordial soup of early earth. These ribonucleotides transformed into RNA which activated DNA genetic material and replicated both prokaryotic and eukaryotic cells.
Evolution of species, established by Darwin in the 19th century, appears quite consistent and reminiscent of the primordial process Nowicki outlines.
With that reflection, Nowicki reminds listeners that evolutionary process should not be thought of as a necessarily progressive improvement. Evolution is chancy. It can either preserve or destroy species. Nowicki wanders back in history to explain classification of species as theorized by Linnaeus in the early 18th century.
Carl Linnaeus (1707-1778, Swedish botanist, zoologist, taxonomist, physician.)
The second doubling of a zygote creates four cells separated in a vertical axis with all genetic material present in each cell. Subsequent doubling is separated on a horizontal axis. These new cells do not have all genetic material enclosed. The new cells have a more limited genetic role. There is significance in that axis change because of the location of genetic material in respective cells. With a change in axis, the viability of one cell carrying all the characteristics of its host goes from certainty to doubtful. The specialization of cells removes some of the genetic material that would contain all the characteristics of the life form.
The zygote at four cells is mature. The next doubling becomes an embryo. All four cells have the genetic material of a male’s and female’s contribution. Each multiplication reduces the size of sister cells until they form a mass that surrounds a vacant space within its middle. This vacant space is the blastocyst stage. The blastocyst is made up of an exterior shell, a middle shell, and an inner shell. Each shell becomes the seat of design for what is to be born.
All amassed cells around the blastocyst carry site specific genetic material of life that forms a living thing.
The process of design in a human begins with an intrusion into the blastocyst without breaking its shells. That intrusion (a human gastrula), around the 7th or 8th day, uses the membranes as laboratories within which genetic codes create skin, bone, internal organs, and the digestive system.
Each of the three membranes are the laboratories of creation. The exterior or outer shell for example would become skin, the middle shell would become organs, the inner shell would become the digestive system.
The next exploration of biology by Nowicki is more suited to students of biology. Nowicki makes a valiant effort to explain the chemistry of ADP and ATP phosphates that provide energy needed for growth and maintenance of life. This part of the lecture series becomes too technical.
As molecules of ATP and ADP break down, they fuel cells of life to act in specific ways to promote growth and maintenance. Like the importance of protein messengers for activation of genetic material, life cannot exist without the energy provided by ATP and ADP. Nowicki diligently tries to explain the mechanics of this phosphate process but loses this reviewer’s interest.
The first inkling of cause for plant growth is noted by Jan Baptist van Helmont in the 17th century. Nowicki explains Helmont planted a tree in a tub of soil. He carefully weighed the soil and tree at the time of planting. Over several years, he observed the growth of the tree. At the end of those years, Helmont weighed the soil and tree. He found a small decrease in the soil’s weight and a gigantic increase in the tree’s weight. Helmont speculates the difference is from water added over the years. Though his conclusion is only partly correct, he paved the way for discovery of photosynthesis.
Jan Baptist van Helmont , a Dutch chemist and physician (1580-1644, On the left with his son on the right.)
That synthesis is a more complete explanation of the weight gain noted in Helmont’s experiment. The fundamental point being made by Nowicki is that species growth and demise is based on resource availability. Jan Ingenhousz completes Helmont’s theory with the discovery of photosynthesis.
Jan Ingenhousz (1730-1799, Dutch physiologist.)
Around 1779, A Dutch physician named Jan Ingenhousz found that green plants use sunlight to synthesize food for plants from carbon dioxide and water.
The remaining lectures are about Malthusian limits to life. There are natural and societal actions (meaning acts of war) that affect species survival. For natural calamities, one is reminded of the Black plague in the 14th and 17th centuries, the Spanish flu after WWI., the Irish famine in 19th century, the great Chinese famine during the “Great Leap Forward”, and now Covid19.
From man’s inhumanity to man, there is the Mongol invasion of Europe in the 13th century, two 20th century World Wars, the holocaust atrocity of WWII that murdered 11,000,000 (6,000,000 of which were Jews), and most recently, an estimated 600,000 dead in the Syrian Civil War.
How many more deaths will there be from Russia’s invasion of Ukraine?
Of course, Nowicki’s attention is on the biology of life. Nowicki explains, the key to balance of nature is biodiversity. Nowicki notes the unprecedented loss of species in the post 20th century world risks life’s future. Nowicki briefly explains how drug discoveries and loss of genetic material from species extinction affects the balance of nature by diminishing the sources and utility of future medical discoveries.
The fundamental point of Nowicki’s view is that no species escape the natural biological limits of life. Nature balances life based on resources available. A listener may imply Nowicki believes humanity is threatened as much by ignorance of biology as of “man’s inhumanity to man”.