These 10 animal facts will amaze you. Color blindness is most often a genetic visual deficiency that limits the colors that an individual can detect. Most people with this condition don't only see in black and white. The colors affected are usually limited to green and red, which often appear as shades of tan or brown.hese 10 animal facts will amaze you. Color blindness is most often a genetic visual deficiency that limits the colors that an individual can detect. Most people with this condition don't only see in black and white. The colors affected are usually limited to green and red, which often appear as shades of tan or brown.
The duration of the QT-interval varies dependent upon how fast the heart is beating, but in normal healthy people, when the heart is beating 60 beats per minute, it is between 350 and 440 milliseconds.
The upper threshold of a normal human resting heart rate is based on age. Cutoff values for tachycardia in different age groups are fairly well standardized; typical cutoffs are listed below: 1â2 days: Tachycardia > 159 beats per minute (bpm) 3â6 days: Tachycardia >166 bpm; 1â3 weeks: Tachycardia >182 bpm; 1â2 months: Tachycardia >179 bpm