DNA and chromosomes are fundamental to understanding how traits are inherited from parents to offspring. DNA, the molecule that carries genetic information, is organized into chromosomes within the nucleus of cells. These chromosomes contain coding regions that provide instructions for characteristic traits, while non-coding regions have other functions. This review will clarify how DNA and chromosomes work together to pass traits from one generation to the next and distinguish between coding and non-coding regions.
DNA: DNA (deoxyribonucleic acid) is the hereditary material in all living organisms. It contains the genetic instructions used in growth, development, and reproduction. DNA is structured as a double helix and is composed of two strands of nucleotides.
Chromosomes: Chromosomes are long, thread-like structures made of DNA and proteins. Humans have 23 pairs of chromosomes, with one set inherited from each parent. Each chromosome contains many genes, which are specific sequences of DNA that code for particular traits.
Coding Regions: Coding regions of DNA are sequences that contain instructions for synthesizing proteins. These proteins are responsible for the expression of traits. For example, a gene in a coding region might instruct cells to produce melanin, influencing skin color.
Non-Coding Regions: Non-coding regions of DNA do not code for proteins but serve other important functions. They may regulate gene expression, provide structural support to chromosomes, or have roles in maintaining genome stability.
Inheritance of Traits: Traits are inherited through the transmission of genetic material from parents to offspring. The combination of genes and their variations (alleles) from each parent determines the traits observed in the offspring. For example, the trait for eye color is determined by specific genes passed down through chromosomes.
Questions to Clarify Relationships:
NGSS Aligned Testing Question
| An individual inherited a new variation in the gene that codes for the production of the prostaglandin receptor. Which question could be asked to clarify how the variation was passed on to the individual? | |
|---|---|
| 1 | Were the father’s white blood cells able to produce gametes with the variation? |
| 2 | Did the receptor lose function due to a lack of prostaglandin molecules? |
| 3 | Was the variation caused by a change in a gene sequence in the mother’s gametes? |
| 4 | Was the prostaglandin receptor with the variation the same size as the original receptor? |
DNA (deoxyribonucleic acid) is the hereditary material in organisms that carries genetic instructions for growth, development, and reproduction. It is crucial for inheritance because it provides the blueprint for traits passed from parents to offspring.
Chromosomes are structures within cells that are made of DNA and proteins. Each chromosome contains many genes, which are segments of DNA that code for specific traits.
Coding regions of DNA are sequences that provide instructions for making proteins. These proteins are responsible for the traits an organism exhibits, such as eye color or enzyme production.
Non-coding regions of DNA do not code for proteins but have roles such as regulating gene expression, providing structural support, and maintaining genome stability.
Traits are inherited through the transmission of genes located on chromosomes from each parent to their offspring. The combination of genes from both parents determines the traits observed in the offspring.
Understanding the difference is important because it helps us comprehend how genetic information is used to produce traits (coding regions) and how other DNA functions, such as regulation and stability, are maintained (non-coding regions).
Genes are specific sequences of DNA that contain instructions for producing proteins. These proteins, in turn, influence the development of physical and biochemical characteristics in an organism.
The combination of genes from both parents contributes to the genetic makeup of the offspring, determining various traits through the interactions of different alleles and genetic variations.
Understanding DNA is fundamental to genetics as it provides the basis for studying how traits are inherited, how genetic disorders arise, and how genetic information is used to produce proteins and influence development.
The significance of studying both coding and non-coding DNA lies in understanding the complete picture of genetic function. Coding DNA reveals how traits are expressed through protein synthesis, while non-coding DNA offers insights into gene regulation, chromosome structure, and genome stability. Both aspects are crucial for a comprehensive understanding of genetics and its implications for health and disease.
*continue your studies by accessing another review sheet below*
HS. Structure and Function: HS-LS1-1 : HS-LS1-2 : HS-LS1-3
HS. Matter and Energy in Organisms and Ecosystems: HS-LS1-5 : HS-LS1-6 : HS-LS1-7 : HS-LS2-3 : HS-LS2-4 : HS-LS2-5
HS. Interdependent Relationships in Ecosystems: HS-LS2-1 : HS-LS2-2 : HS-LS2-6 : HS-LS2-7 : HS-LS2-8
HS. Inheritance and Variation of Traits: HS-LS1-4 : HS-LS3-1 : HS-LS3-2 : HS-LS3-3 : HS-LS1-8
HS. Natural Selection and Evolution: HS-LS4-1 : HS-LS4-2 : HS-LS4-3 : HS-LS4-4 : HS-LS4-5
Disclaimer: The information provided is intended to serve as a study guide based on a contextual analysis of the NGSS standards for the Life Science Biology assessment. These study guides should be used as a supplement to your overall study strategy, and their alignment to the actual test format is not guaranteed. We recommend that you consult with your instructor for additional guidance on exam preparation.