Worksheets and No Prep Teaching Resources
Worksheets and No Prep Teaching Resources
Reading Comprehension Worksheets
Life Science
DNA Structure

Life Science
Life Science


DNA Structure
Print DNA Structure Reading Comprehension with Sixth Grade Work

Print DNA Structure Reading Comprehension


Reading Level
     edHelper's suggested reading level:   grades 6 to 8
     Flesch-Kincaid grade level:   7.12

Vocabulary
     challenging words:    adenine, as-id, chromatid, cytosine, double-helix, guanine, helix, nucleotide, nucleotides, recessive, thymine, deoxyribonucleic, radiation, embryonic, blueprint, mutation


DNA Structure
By Cindy Grigg
  

1     An embryonic cell divides again and again. Where there was one cell there are two, then four, then eight, and so on. Each holds all the genetic information needed to create a new human being. Your fingernails grow nonstop, day in and day out. The cells of your fingernails somehow generate all of the protein that makes up your nails. How is this protein created? How, exactly, do these cells make copies of themselves? The answers to these questions are DNA replication and protein synthesis.
 
2     When organisms reproduce, traits are passed from parent to offspring. These traits are carried in DNA, the genetic material found in a cell's nucleus. DNA acts like a blueprint for the cells of an organism, instructing the cells how to put together materials to produce certain traits.
 
3     DNA stands for deoxyribonucleic acid (pronounced de-ox-ee-ribe-o-new-clee-ick as-id). It's made of just a few kinds of atoms: carbon, hydrogen, oxygen, nitrogen, and phosphorus. The traits that make organisms different from one another are coded for in their DNA. Chromosomes are made of DNA. Chromosomes are genetic structures that contain the information used to direct a cell's activities and make new cells. They are found in the nucleus of a cell.
 
4     A person has 46, or 23 pairs, of chromosomes. Our cells have two copies of each chromosome. One came from the mother, and one from the father. The chromosome starts as half of the familiar X. As the cell grows, it replicates the DNA to make the other half of the X, which is identical. When the cell divides, each daughter cell receives half of each chromosome (called a chromatid). The two copies of the gene are alike on one chromosome but the "matching" pair of chromosomes may have slightly different genes (dominant or recessive alleles) as one came from the mother and one from the father. The dominant gene of the two is the one that is expressed. For example, if one parent gives a gene that carries the trait for blue eye color and the other parent gives a gene that carries the trait for brown eye color, the child would have brown eyes. The trait for brown eye color is dominant, and that is the color that would be expressed in the child.
 
5     DNA is a very large molecule with a shape like a twisted ladder. You have probably heard of the DNA molecule referred to as a double-helix. The rungs of the ladder are made up of molecules called bases. These nucleotide bases are adenine, thymine, guanine, and cytosine. The bases always pair up so that adenine is joined with thymine (A-T) and cytosine is joined with guanine (C-G). Each rung of the ladder is made of two bases - one for each side of the ladder.

Paragraphs 6 to 11:
For the complete story with questions: click here for printable



Weekly Reading Books

          Create Weekly Reading Books

Prepare for an entire week at once!


Feedback on DNA Structure
Leave your feedback on DNA Structure   (use this link if you found an error in the story)



Life Science
             Life Science


Science
             Science


    Careers in Science  
 
    Caring for Earth  
 
    Clouds  
 
    Dinosaurs  
 
    Earth's Land  
 
    Earth  
 
    Earthquakes  
 
    Electricity  
 
    Energy  
 
    Erosion  
 
    Food Pyramid  
 
    Food Webs and Food Chain  
 
    Forces and Motion  
 
    Fossils  
 
    Health and Nutrition  
 
    How Things Work  
 
    Landforms  
 
    Life Science  
 
    Light  
 
    Magnets  
 
    Matter  
 
 
    Moon  
 
    Natural Disasters  
 
    Photosynthesis  
 
    Plant and Animal Cells  
 
    Plants  
 
    Rocks and Minerals  
 
    Science Process Skills  
 
    Scientific Notation  
 
    Seasons  
 
    Simple Machines  
 
    Soil  
 
    Solar System  
 
    Sound  
 
    Space and Stars  
 
    Sun  
 
    Tsunami  
 
    Volcanoes  
 
    Water Cycle  
 
    Water  
 
    Weather  
 



Copyright © 2017 edHelper