Invertebrate Definition Invertebrates are animals that don’t have a backbone. The vertebral column is another name for the backbone. Over 90% of all species on Earth are invertebrates, and invertebrate species have been found in the fossil record as far back as 600 million years ago. Molecular biology studies suggest that all invertebrates evolved from … Read more
Phosphorus Cycle Definition The phosphorus cycle is the process by which phosphorus moves through the lithosphere, hydrosphere, and biosphere. Phosphorus is essential for plant and animal growth, as well as the health of microbes inhabiting the soil, but is gradually depleted from the soil over time. The main biological function of phosphorus is that it … Read more
Internal Respiration Definition During internal respiration, oxygen diffuses from the blood into the interstitial fluid and into the cells. The waste and carbon dioxide are also diffused from the cells to the blood in the other direction. Blood cells release oxygen when the oxygen concentration in capillaries of blood vessels is low, which is usually … Read more
Carboxyl Group Definition The carboxyl group is one of many functional groups that attach to larger molecules to give them their properties. Carboxylic acids are organic molecules with a carboxyl group that serve a variety of functions. Carbon forms the carboxyl group, which is bonded to oxygen and hydroxyl groups. A hydrogen bonded to an … Read more
Accepting a student to Harvard University is no easy feat. Every year, this Ivy League school receives about 35,000 applications from around the world, and it has an acceptance rate of 4.7%. This means that fewer than five out of every 100 applicants are accepted. Harvard ranks among the most–if not the most–selective colleges because … Read more
Are you preparing to enroll in college, and wondering how many credits you will need to earn in order to graduate? The answer to this question can vary depending on a few factors, such as the degree program you are pursuing and the requirements of the college or university you attend. In this article, we … Read more