Harcourt Science(Fifth Grade)-Chapter 1 Lesson 2 Quiz

Explanation
Epithelial tissue covers and lines the body, forming the outer layer of the skin and lining the internal organs and cavities. It serves as a protective barrier, preventing the entry of pathogens and regulating the exchange of substances between the body and its environment. Epithelial tissue also plays a role in absorption, secretion, and sensation. Therefore, the correct answer is epithelial.

Explanation
The given options, kleenex-tissues, organs, and tendons, are not directly related to helping blood clot if you get cut. Kleenex-tissues are used for blowing noses or wiping hands, organs are part of the body's systems, and tendons are connective tissues that attach muscles to bones. None of these options have a direct role in blood clotting. Therefore, the correct answer is "None of these."

Explanation
The correct answer is esophagus. The esophagus is a long tube that connects the throat to the stomach. It carries food from the mouth to the stomach through a series of muscular contractions called peristalsis. The trachea is the windpipe, which carries air to and from the lungs. The heart is a muscular organ that pumps blood throughout the body. Villi are small finger-like projections in the small intestine that help absorb nutrients from food.

Explanation
Partly digested food moves from the stomach into the small intestine. The small intestine is responsible for further digestion and absorption of nutrients from the food. It is called the small intestine because it is narrower and longer compared to the large intestine. The large intestine mainly absorbs water and electrolytes from the remaining undigested food, forming feces.

Explanation
The correct answer is saliva. Saliva is produced by the glands in your mouth. It helps in the process of digestion by moistening food, making it easier to swallow. Saliva also contains enzymes that begin the breakdown of carbohydrates in the food. Spit is another term for saliva, so both options are correct. Villi are small finger-like projections in the small intestine that aid in nutrient absorption, while blood is a fluid connective tissue that carries oxygen and nutrients throughout the body.

Explanation
Tendons are the correct answer because they are the connective tissues that connect bones to muscles. Ligaments, on the other hand, connect bones to other bones. Intestines and atoms are not connective tissues and do not have a role in connecting bones to muscles.

Explanation
White blood cells, also known as leukocytes, play a crucial role in helping the body fight diseases. They are part of the immune system and are responsible for identifying and destroying pathogens, such as bacteria and viruses, as well as other harmful substances in the body. White blood cells are diverse and come in different types, each with specific functions in immune response. Their ability to engulf and destroy foreign invaders makes them essential in protecting the body from infections and maintaining overall health.