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.
D. To help oxygen get into blood vessels
Answer:
D. A segment of DNA molecule
Explanation:
Gene is a segment of a DNA molecule that holds instruction needed for the synthesis of useful products (protein). Ideally, DNA is the storage material of genetic information in a cell. The DNA harbors the GENE, which itself is being expressed in order to use the information contained in it to produce useful products responsible for the phenotype of an organism.
A gene contains sequences made up of nucleotide bases that determines the sequence of amino acids to be produced, and ultimately the type of protein.
