Explanation

If a codon consisted of only two nucleotides, there would be 16 possible codons. 

Since there are four possible nucleotides (A, C, G, and T), each position in a two-nucleotide codon could be filled by any of these nucleotides.

Therefore, to calculate the total number of possible codons,

We multiply the number of possibilities for the first position by the number of possibilities for the second position:

4 nucleotides * 4 nucleotides = 16 possible codons. 

Explanation

 The term for similarity in characteristics resulting from common ancestry is Homology. 

Homology refers to the shared features between organisms that are derived from a common ancestor. 

Explanation

Sticky ends are formed when a restriction enzyme cuts DNA at specific locations, leaving short, single-stranded overhangs with unpaired bases at the ends.

These unpaired bases can then form hydrogen bonds with complementary unpaired bases on another DNA fragment, allowing them to "stick" together, hence the name "sticky ends". 

Explanation

• The ozone layer in the stratosphere absorbs and restricts ultraviolet (UV) radiation from the sun.
• It protecting life on Earth from harmful UV rays.

Explanation

Explanation

Explanation

The backbone of DNA consists of alternating deoxyribose sugar and phosphate groups, linked by phosphodiester bonds.

Key Information:

Sugar-Phosphate Backbone:

• Provides structural stability to the DNA double helix.
• Directionality: 5’ (phosphate) to 3’ (sugar) orientation.

Nitrogenous Bases (A, T, C, G):

• Attached to the sugar but not part of the backbone.
• Form hydrogen bonds to create base pairs (A-T, C-G).

Explanation

Nucleic acids (DNA/RNA) are present in:

Nucleus:

• Contains genomic DNA (eukaryotic cells).

Mitochondria:

• Have their own mtDNA (vital for energy production).

Chloroplasts (in plants/algae):

• Contain cpDNA for photosynthesis-related functions.

Explanation

ATP (Adenosine Triphosphate) is called the energy currency of the cell because it stores and provides energy for cellular activities.

It releases energy when converted to ADP (Adenosine Diphosphate), which is then recycled back into ATP through cellular respiration.

Explanation

Cholesterol is a vital precursor in the biosynthesis of:

Vitamin D:

• Cholesterol converts to 7-dehydrocholesterol in the skin, which forms vitamin D₃ under UV light.

Steroid Hormones:

Cholesterol is the backbone for:

• Sex hormones (testosterone, estrogen, progesterone).
• Adrenal hormones (cortisol, aldosterone).