By studying fossils, scientists can learn how much (or how little) organisms have changed as life developed on Earth. There are gaps in the fossil record because many early forms of life were soft-bodied, which means that they have left few traces behind. This is why scientists cannot be certain about how life began.
Answer:
Pakicetus had an ear bone with a characteristic specific to whales and a distinctive long skull shape of a whale's.
Pakicetus
• Pakicetus was a wolf-sized animal and was a carnivore that at certain occasions consumed fish had exhibited features of its anatomy that associated it to the modern cetaceans, porpoises, whales, and dolphins.
• It had the body of a land animal, however, its head exhibited the distinctive long skull similar to a whale.
• With time, the fossils also showed that Pakicetus possessed an ear bone with a characteristic specific to whales.
Thus, pakicetus can be considered as the first whale who exhibited certain similar anatomic features like that of a whale.
Find out more information about Pakicetus anatomy here:
brainly.com/question/16395727
Explanation:
THE EXCRETORY SYSTEM
Answer: The attachment shows the nephron which is the functional unit of the kidney.
It does the work of urine formation through 3 distinct processes.
-Ultra filtration( Small molecules are forced out of the selectively permeable membrane of the glomerulus into the Bowman's capsule under regulated pressure.these molecules are from the blood in the glomerulus brought in by the afferent arteriole.
- Selective reabsorption ( Useful molecule and iron such as glucose and sodium are reabsorbed back into the blood as the filtrate flows through the tubule(nephron)
-Tubular Secretion. ( Movement of molecules not filtered by the glomerulus during the initial stage of filtration back into the filtrate through the renal capillaries.
Stella's urine sample shows the presence of large protein (ULTRAFILTRATION)
John's blood test report indicates a high toxin level ( ULTRAFILTRATION AND TUBULAR SECRETION)
Miguel's blood test shows an increase in metabolic waste( ULTRAFILTRATION AND TUBULAR SECRETION)
Janice's urine report shows the presence of vital materials ( SELECTIVE REABSORPTION).
Answer:
1. While Biology is the study of living things, living things themselves are made up of chemical composition. Our survival is dependant on the reactions taking place inside and outside the body. Hence, to understand living things, biologists needs a good understanding of chemistry.
2. 170 pm is the radius of a Carbon Atom.
3. The vast majority of the mass of an atom is concentrated in its nucleus
4. Protons are found in the nucleus of the atom. This is a tiny, dense region at the center of the atom. Protons have a positive electrical charge of one (+1) and a mass of 1 atomic mass unit (amu), which is about 1.67×10−27 kilograms.
5. Neutrons are located with protons in the nucleus; they too exchange mesons with protons and with each other to form the strong nuclear force, but they do not have to overcome the repulsion from Coulomb forces since neutrons are not charged.
