Answer:
Explanation:
An element only has <u>one</u> type of atom and cannot be broken down by chemical means.
Let's analyze the answer choices.
1. This has two types of atoms, so it cannot be an element. It has more than one type of atom.
2. This has two types of atoms that are bonded together. It cannot be an element because there is more than one type of atom and the bonds can be broken.
3. This has one type of atoms, so it is an element.
Therefore the best answer choice is 3.
Answer:
B) Nucleotides
Explanation:
The nucleotides sequence of DNA molecules determines the protein that will be produced. The mRNA molecules carry a copy of DNA to ribosome. the nucleotides consist of three parts- nitrogenous base, pentose sugar and a phospate group. There have more than six billion nucleotide pairs in a cell.
Answer:
False, all plants cells have cell membrane, in addition most of them have also cell wall. They have both
Deserts, savannas, and grasslands.
Every species exhibits variations based on various genes being activated at various times. An example with humans can be eye color or hair color. What species means is that all members of a species can procreate with healthy, capable of procreating progeny, but anything else is just a variation.
