Answer:
Because DNA molecules are extremely long.
Explanation:
DNA molecule is made up of only four types of nucleotides that are adenine, guanine, cytosine, and thymine. These four types of nucleotide encode all the information necessary for the formation and working of the entire organism because each DNA strand is as long as 2 meter which contains millions of base pairs.
The four nucleotides are arranged in the DNA strand with many different combinations which results in the formation of codons sequence that contains all the information about the cell. This long DNA is compressed several times to fit in the nucleus.
Capillaries have thin walls, only one cell thick, that allow them to effectively perform their function.
Answer:
The repeating subunits of DNA are ribonucleotides whereas in RNA they are deoxyribonucleotides.
Explanation:
Ribonucleotides are repeating subunit of RNA while the deoxy-ribonucleotides are repeating subunits of DNA. That why RNA full form represent the ribonucleic acid and DNA represent deoxyribonucleic acid.
Actually the word "deoxy" means one oxygen is removed or less in DNA. The DNA lacks the one oxygen atom of hydroxyl group at carbon number two of ribose sugar. While RNA have the hydroxyl group at carbon number two of hydrogen atom.
The removal of one hydrogen atom in DNA make it more stable than RNA because DNA is made specifically to store genetic information and needed to be strong. The oxygen atom in RNA makes it vulnerable for attack by other biological molecules.
Answer:
Endocytosis
Explanation:
the process of capturing a substance or particle from outside the cell by engulfing it with the cell membrane. The membrane folds over the substance and it becomes completely enclosed by the membrane. ... The plasma membrane engulfs the solid material, forming a phagocytic vesicle.
