Chromosomes come in pairs and contain genes, which code for inherited traits. If a gene is always expressed when present, it is called dominant and is represented by a capital letter. A dominant gene will be expressed whether an individual is pure and has two copies of the dominant gene or is hybrid and contains one dominant copy and one copy of another gene. In the case of hybrids, the dominant gene hides the expression of the recessive gene. A recessive gene is expressed only when it is pure, and it is represented by a lowercase letter.
In pea plants, the gene for round pea shape is dominant and the gene for wrinkled pea shape is recessive. A plant that produces wrinkled peas must be pure for the wrinkled gene, meaning it must contain two copies of the wrinkled gene. A plant that produces round peas can either be pure for the round gene or be hybrid and have one gene for round shape and one gene for wrinkled shape.
Punnett Squares are charts used to predict the odds of specific gene combinations in offspring. Below is a Punnett Square of a cross between a pea plant purebred for wrinkled peas and a pea plant that produces round peas.
Which of the following describes the offspring of this cross?
Explanation
Since a plant that produces wrinkled peas must contain two copies of the wrinkled gene (r), half of the offspring in the chart contains the genes for the wrinkled peas (rr) and thus will produce wrinkled peas. The offspring in the other half of the chart contains one for round peas (R) and one for wrinkled peas (r). Since the gene for round pea shape is dominant and the gene for wrinkled pea shape is recessive, these offspring will produce round peas.
Employees at GetWell research labs are analyzing mechanical waves, which require a medium to pass through, and electromagnetic waves, which travel through space. Jose Gonzalez IV is studying electromagnetic waves and their potential, real-world health and medical applications. He records the lengths of the various waves, noting that radio waves are the longest, while Gamma rays are the shortest. When calculating the frequency of the wave, or the number of wavelengths that occur in a distinct amount of time, Jose notes that there is an inverse relationship between the frequency of a wave and its period, which is the time it takes for a single wave to occur.
| Wave type | Wave length size | Application |
| Radio Waves | Grater than 30cm | Aircraft Naviagtion, TV, AM/FM Radio |
| Infrared Waves | 30cm - 1mm | Microwave Ovens, Mobile Phones |
| Visible Light | 1mm - 700nm | Remote Controls, Toasters, Night Vision |
| X-Rays | 700nm - 400nm | Physical Therapy, Light Bulbs, Photography |
| Ultraviolet Light | 400nm - 60 nm | Sanitation, Air Purification, Forgery Detection |
| X-Rays |
60nm - \(1 \times 10^{4}\)nm |
Medical Examination, Cancer Treatment |
| Gamma Rays | 0.1 nm - \(1 \times 10^{5}\) nm | Cancer Treatment, Food Irradiation |
Based on the information provided, which types of waves have potential medical applications? Choose all that apply.