Answer:
White blood cells.
Explanation:
The first line of defence (or outside defence system) includes physical and chemical barriers that are always ready and prepared to defend the body from infection. These include your skin, tears, mucus, cilia, stomach acid, urine flow, 'friendly' bacteria and white blood cells called neutrophils.
<span>Sugar is carbohydrates, fats are lipids, amino acids are proteins, and nucleotides are nucleic acid. They're all about the same healthiness because everyone needs all four for their diet. Carbohydrates give us energy, lipids provide energy, protein builds our structure, and nucleic acid stores our genetic information.</span>
A: Taxon.
The terms order and class both refer to 2 specific levels that are a part of Linnaeus' classification systems.
To divide reproductive cells