Protons have a positive charge. The number of protons in a nucleus determines the identity of the atom (element) and this number is called the atomic number.
D. Proton
<u>Answer:</u>
Recent evidence suggest that feathers evolved from scales and suggest that 'feathers and pycnofibers' could be homologous.
<u>Explanation:</u>
- One of the major difficult issue related to bird evolution is the evolution of feathers.
- Feathers are considered as the most 'complex integumentary structures' which are found in vertebrates.
- Evolutionary developmental biology suggests that the 'planar scale structure' is been modified for developing into feathers by 'splitting' to form web like structures.
- Scales and Feathers consist of 'two distinct form of keratin' so it was thought that 'each type was exclusive skin structure' but recent study suggests that they are developmental expressions of same skin structures.
Answer:
boiling, freezing, refridgeration, and fertilizer.
Explanation:
the first three have to do with temperature, which tends to kill bacteria. Pesticides kill bacteria by poisoning them
Answer: the rocks density and the waters density would stay the same. It does not change
Explanation:
Answer:
Radiometric dating methods
Explanation:
Absolute dating is the process of determining an age on a chronological or specified time scale in which events occurred in archaeology and geology. Absolute dating can be determined by using properties of the atoms that make up materials.
The most common method of absolute dating uses by geologists is radiometric dating methods which is based on the natural radioactive decay of certain elements such as potassium and carbon found in the rocks. By comparing the ratio of parent isotope with a known half-life to daughter product in the rock, the age of the rock can be determined.
The carbon-14 isotope is used in radiocarbon dating, but is only useful for measuring recently formed rocks in the geologic past. The decay of Potassium-40 isotope known as potassium-argon (K-Ar) method allows dating of materials that up to 1,000 billion years old.