Enzymes are catalysts that can be used more than once. If a substance needs to get broken down then it can use the corresponding enzyme to attach itself and break it down into simpler substances. After this is gone, the next substance might come up and attach itself to the enzyme like a lock-and-key model.
Therefore the answer is A) Enzymes accelerate chemical reactions without getting used up in the process.
Answer: KIDNEY (URINARY/EXCRETORY SYSTEM) helps regulate water and electrolyte balance.
Kidney is an important organ of our urinary system that regulates chemical composition of blood, regulates water and electrolyte balance, etc in our body. Kidney is made up of nephron cells that filters water, reabsorbs amino acids, secrete and excrete urine outside the body.
I think the answer would be B. Genealogy.
The answer would be C) grass, field mouse, snake, hawk.
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