A radioactive element is an element which is subject to spontaneous degeneration of its nucleus followed by the emission of alpha, beta and gamma particles. All elements with atomic numbers greater than 83 are radioactive.
The given phrases that describe radioactive elements are-
They have a consistent number of particles
- the particles are alpha, beta and gamma particles.
They have a half-life that determines their rate of decay.
Explanation for other options:
Not all elements occur in nature. Radioactive decay rates may not be constant as the decay happens when a radioactive substance emits a particle. It is not possible to predict exactly when a given atom of a substance will emit a particular particle. When the radioactive element release energy and particles, it decays.
Answer: The correct answer is Enzymes.
Process of digestion involves the breakdown of large complex molecules ( like carbohydrates, and proteins) present in the food into smaller soluble molecules ( like glucose and amino acids) that can be absorbed by bloodstream and transported to various body organs.
Protein in the stomach is broken down into amino acids with the help of enzyme called as pepsin ( a protease). It is an endo-peptidase that is produced in the stomach and helps in the digestion of proteins at acidic pH of the stomach ( 1.5 to 2).
Answer:
The process by which organisms that are better suited to their environment than others produce more offspring. As a result of natural selection, the proportion of organisms in a species with characteristics that are adaptive to a given environment increases with each generation.
Explanation:
A.) carbohydrates are large molecules made up of monosaccharides and are used by organisms for energy storage.
Hope I helped! :)
