More than 4.2 million Americans aged 40 years and older are either legally blind (having best-corrected visual acuity of 6/60 or worse (=20/200) in the better-seeing eye) or are with low vision (having best-corrected visual acuity less than 6/12 (<20/40) in the better-seeing eye, excluding those who were categorized as being blind).
The leading causes of blindness and low vision in the United States are primarily age-related eye diseases such as age-related macular degeneration, cataract, diabetic retinopathy, and glaucoma. Other common eye disorders include amblyopia and strabismus.
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Refractive Errors
Refractive Errors
Refractive errors are the most frequent eye problems in the United States. Refractive errors include myopia (near-sightedness), hyperopia (farsightedness), astigmatism (distorted vision at all distances), and presbyopia that occurs between age 40–50 years (loss of the ability to focus up close, inability to read letters of the phone book, need to hold newspaper farther away to see clearly) can be corrected by eyeglasses, contact lenses, or in some cases surgery. The National Eye Institute states that proper refractive correction could improve vision among 150 million Americans.
<h2><em>In general, a scientific law is the description of an observed phenomenon. It doesn't explain why the phenomenon exists or what causes it. The explanation of a phenomenon is called a scientific theory. It is a misconception that theories turn into laws with enough research</em></h2>
Answer:
- Ecological levels to consider in this study: organism, population and community
- Approach: I would use an observational approach to study this bird species
Explanation:
The levels of the ecological organization include the organism, population, community, ecosystem, and biosphere (from simplest to most complex). In this exploratory study, it is imperative to consider: 1-morphological, physiological and behavioral adaptations of the bird species (i.e., organismal-level), 2- size/density/structure of the bird population (i.e., population-level), and 3-interactions between bird population and other populations (i.e., community-level). The higher ecological levels, i.e., ecosystem-level (relationships between the community and abiotic factors ) and biosphere-level (biosphere = planet Earth), can be in this case disregarded because this study is centered on a focus bird species. Moreover, it is expected to apply an observational strategy because nothing is currently known about the focus bird species. The experimental and modeling approaches seem more suitable to test a particular hypothesis being discussed (it is not the case for this study).
Noctiluca is a dinoflagellate