<span>The correct answer is a.
Exocrine glands secrete substances through a duct; endocrine glands release substances into the blood.</span>
For example, exocrine glands are sweat, salivary, mammary, lacrimal glands… Endocrine glands excrete hormones. Examples of this type of glands are the pineal gland, pituitary gland, thyroid gland, parathyroid gland, pancreas, ovaries, testes, hypothalamus and adrenal glands.
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The answer TRUE they do not have a fossil record.
Explanation:
Genetic conditions such as trisomy (three chromosomes) or monosomy (only one chromosome). They can also determine the fetus' gender by looking at the XY / XX chromosomes.
Only DNA contains the base, thymine, which binds with adenine. Whereas RNA contains the base, uracil, which binds with adenine. Also the structure of their sugars are different: Deoxyribose, in DNA, contains one less oxygen than RNA's ribose sugar.