The Backbone of a Strand of Nucleic Acid Consists of

question 29

Multiple Choice

The backbone of a strand of nucleic acid consists of

• A) phosphate units only.
• B) phosphate and sugar units.
• C) polyester.
• D) phosphate, sugar, and nitrogen base units.
• E) sugar units only.

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Definitions:

Fossil Record

The collection of physical and geological evidence of organisms that lived in the past, preserved in the Earth's crust.

Cretaceous Period

A division of Earth’s history lasting from about 145 to 66 million years ago, marked by the dominance of dinosaurs and the appearance of flowering plants.

Gymnosperms

Seed-producing plants such as conifers that do not have flowers or fruit, with seeds often exposed or on the surface of scales or leaves.

Bryophytes

Non-vascular plants that include mosses, liverworts, and hornworts, characterized by their life cycle stages and lack of vascular tissue.