We often hear the terms protists, protozoans, and metazoans; briefly explain the relationship among them
What will be an ideal response?
Answer: When we think about the origin of animals, we often think of protists. Protists are single-celled, eukaryotic organisms that possess a membrane-bound nucleus and organelles. Protists are a very diverse group of distantly-related organisms, and hence assigned to more than 50 phyla. Some protists are animal-like and mobile, and because locomotion was considered a unique trait of animals, animal-like protists were once considered to be the ancestors of animals and were referred to as protozoans. Currently, the term protozoan has no meaningful evolutionary basis. The term metazoan was originally created to differentiate single-celled protozoans from multicellular animals. "Metazoan" and "animal" are often used synonymously.
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Answer the following statements true (T) or false (F)
1. All compounds in the human body are, by definition, organic compounds. 2. Organic compounds must have either a C-C or C-H bond. 3. Water is an inorganic compound. 4. Aqueous solutions have water as the solvent. 5. In a dehydration synthesis reaction, water is always a reactant.
When we get cold, our body compensates by shivering. In this example, what role do the muscles play?
A. Receptors B. Control centers C. Stimuli D. Effectors
The follicular phase of the menstral cycle is also known as the _______________ phase of the endometrium.
A) proliferative B) luteal C) secretory D) menstruation E) menarche
How much blood does the average-sized adult have?
A. 2 liters B. 5 liters C. 4 liters D. 7 liters