A contact lens is a lens placed on the cornea of the eye.
Importance of buffers in contact lens products:
Buffers: They aim to keep the pH of the solutions at values between 6.6 and 7.8 in order to maintain the lens parameters and the effectiveness of the solutions. They are made by the combination of an acid and its sodium salt (phosphate and acetate for example). Borate and citrate buffers are used.
Importance of isotonicity in contact lens products:
The solution composed by isotonic saline solution.
Isotonia is expressed by osmolarity or cryoscopic lowering
- 0.236 to 0.446 mOsmoles / l (increases during the day)
- If the osmolarity of the mixture is different from that of the tears, it causes discomfort and irritation
• Increased tear secretion
• Increase the blink frequency
- If hypotonia, entry of water to the epithelial cells, if hypertonia: inverse
- Osmolarity restored 1 or 2 minutes after instillation
Answer: Systolic pressure.
Explanation:
Every time the heart beats, it pumps blood into the arteries, which are vessels through which blood circulates from your heart to your tissues with the oxygen and nutrients they need. Blood pressure is the force of the blood pushing against the walls of the arteries, and is highest when the heart beats, pumping blood, which is measured as systolic pressure (i.e., when the heart contracts). On the other hand, diastolic blood pressure refers to the pressure of blood in the artery when the heart relaxes between beats (i.e., when the heart relaxes). Since there are two types of pressures, blood pressure readings are given in two numbers, with the top number being the systolic pressure and the bottom number being the diastolic pressure.
For example, if the systolic pressure measured in a person is 125 millimeters of mercury (mm Hg) and the diastolic pressure is 85 mm Hg, the blood pressure is recorded as 125/85.
So, <u>the systolic blood pressure is registered with the stethoscope when the cuff is deflated.</u> When two heartbeats are heard, the pressure gauge reading is recorded. <u>When the heartbeat ceases, the cuff pressure is released and the diastolic pressure is measured at this time.</u>
An example of sustainable resource use is the use of predators and parasites to,
<span>control insects</span>
The three main parts of RNA nucleotide are:
- A nitrogenous base
- A pentose sugar and
- One or more phosphate groups.
