In this episode of Crash Course Biology, we’ll learn about the ways population genetics reveals how groups of living things evolve—by comparing genetic similarities and differences. We’ll discover the most genetically diverse species of...

Different dogs look incredibly different - but that doesn't mean they are necessarily more diverse.

A species is a group of closely related organisms capable of interbreeding and producing fertile offspring, and speciation is the evolutionary process by which new species arise. Speciation can occur through anagenesis (gradual...

How are new species created? An insight into the key evolutionary processes, played out over many generations, which lead to speciation. Biology - Adaptation And Evolution - Learning Points. We all originate from a single cell, so why...

When Darwin first proposed the theory of evolution by natural selection 150 years ago it was revolutionary. What scientific evidence supports this theory? Biology - Adaptation And Evolution - Learning Points. Since Darwin proposed his...

Cholesterol Structure (Part 1 2)

Dr. Scott Smith, NASA nutritionist and the manager for nutritional biochemistry, discusses the differences in the way astronauts have to eat in space versus the way we eat here on Earth. HWHAP Episode 43.

In this video, we explore the arteries supplying the tissues and organs of the thoracic cavity, especially those originating from the thoracic aorta.

*** Note that while most individuals' rib 7 attaches to the sternal body, some peoples' rib 7 attaches to both the sternal body and xiphoid.