Answer:
D. they're all made up of cells
Answer: D
Explanation: The consumption of fish especially the small fish e.g shellfish is by far the most significant source of ingestion-related mercury exposure in humans and animals.
Explanation:
Worms are invertebrate animals with bilateral symmetry. Worms have a definite anterior (head) end and a posterior (tail) end. The ventral surface of worms and other organisms is the bottom side of the body, often closest to the ground. The dorsal surface is located on the upper part of the body facing the sky. The lateral surfaces are found on the left and right sides of the body. Figure 3.35 compares bilateral symmetry in a whale shark and a swimming plychaete worm. Organs for sensing light, touch, and smell are concentrated in the heads of worms. They can detect the kinds of environment they encounter by moving in the anterior direction
Answer:
Absorption and secretion would be impossible within the digestive tract.
Explanation:
Epithelium is one of the tissues found in humans. It is classified as either simple or stratified depending on the number of cell layers. Simple epithelial tissues have one layer of cells while stratified have many layers of cells. Based on the shape, epithelial tissues can either be squamous, columnar or cuboidal.
Due to the single-layer of the simple epithelial tissues, they line the walls of secretory or absorptive organs e.g organs of digestive tract. The stratified epithelium is majorly for protective function due to the number of cell layers it possess and not a good type of epithelium for locations where absorption and secretion of substances is common e.g digestive tract.
Hence, if a genetic mutation causes a person's digestive tract to have stratified columnar epithelium instead of simple columnar epithelium, ABSORPTION AND SECRETION of chemical substances, which is a key feature of organs (stomach, intestine) that make up digestive tracts, will be impossible.
