Near sightedness is a condition whereby the eyeball is too long or cornea has excess curvature such that light entering the eye is focused in front of the retina rather on the retina itself.
The exact cause of nearsightedness is unknown but there are two factors that may be responsible for its development.
1. Visual stress
2. Heredity
Individuals who spend considerable time reading or working at a computer or engage in other types of intense close visual work may develop nearsightedness.
There is credible evidence that many people inherit nearsightedness or are at least predisposed to the condition, especially if both parents suffer from the condition.
Far sightedness (hyperopia) is a condition where the eye is shorter than normal, the cornea is not curved quite enough or the lens sits further back in the eye than is normal.
This condition can be inherited especially if both parents suffer from it.
The other cause is through diseases like diabetes or glaucoma.
Crossed extensor reflex action prevents one from falling when your foot catches while walking.
Crossed extensor reflex:
- A withdrawal reflex is the crossed extensor reflex. In the withdrawing limb, the extensors relax while the flexors contract, but in the other limb, the opposite happens.
- Contralateral means that the crossed extensor reflex takes place on the side of the body that is opposite from the stimulus.
- Afferent nerve fiber branches travel from the stimulated side of the body to the opposite side of the spinal cord to cause this response.
- They connect with interneurons there, which then stimulate or inhibit alpha motor neurons to the muscles of the opposing leg.
Learn more about the Reflex action with the help of the given link:
brainly.com/question/17212995
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Answer:
your baby may be at increased risk of: Excessive birth weight. Extra glucose in your bloodstream crosses the placenta, which triggers your baby's pancreas to make extra insulin.
Explanation:
Offensive players may toss the ball backwards to any player on their team from any area of the playing field. This sideways or backwards toss is called a BACKWARDS PASS. I hope this helps.