What is the main function of the nervous system in the human body?Lesson 5 Page 2, watch the video in L5 Pg 8

Question

What is the function of the esophagus?Lesson 6 Page 3&4
What animal is used most often as an example of human body systems?Lesson 8 Page 2
Of the models that have been discussed in this unit, which one models blood cells the best?Lesson 8 Page 2 & 8

In 3-5 complete sentences describe the human respiratory system - the organs and their functions. Lesson 5 Page 2 & 3, Lesson 7 Page 2

In 3-5 complete sentences describe 2 human body systems - the organs and how they work together in the human body. Lesson 6 Page 10 Question #1, Lesson 7 Page 2, and L7 Pg 4 Question 1- in the T chart

In 3-5 sentences explain 2 similarities and 2 differences in plant and animal cells. Lesson 3 page 2, Lesson 4 page 2

Answer 1

1. Main Function of the Nervous System: The main function of the nervous system in the human body is to receive, process, and respond to sensory information. It allows for communication between different parts of the body and coordinates activities by transmitting signals throughout the body via neurons. This system plays a critical role in controlling both voluntary actions, such as movements, and involuntary actions, such as reflexes.

2. Function of the Esophagus: The esophagus is a muscular tube that connects the throat (pharynx) with the stomach. Its primary function is to transport food and liquids from the mouth to the stomach for digestion. The esophagus accomplishes this through a series of rhythmic contractions known as peristalsis, which pushes food downward despite the force of gravity.

3. Animal Used as an Example of Human Body Systems: The animal most often used as an example of human body systems is the rat. Rats share many physiological and anatomical similarities with humans, making them a common model for studying human biology and diseases.

4. Model that Best Models Blood Cells: The model that best represents blood cells is often a spherical or disc-shaped model, which accurately depicts the biconcave shape of red blood cells that maximizes their surface area for oxygen transport. This model provides a clear visualization of the physical characteristics and functionality of blood cells.

5. Human Respiratory System Description: The human respiratory system consists primarily of the nose, pharynx, larynx, trachea, bronchi, and lungs. The nose and pharynx act as entry points for air, which is warmed and moistened before entering the larynx and trachea, where it travels to the lungs. Within the lungs, the bronchi branch into smaller bronchioles that lead to alveoli, where gas exchange occurs, allowing oxygen to enter the blood while carbon dioxide is expelled.

6. Two Human Body Systems Description: The circulatory system and the respiratory system work closely together to supply oxygen to the body and remove carbon dioxide. The heart and blood vessels in the circulatory system transport oxygen-rich blood from the lungs to the tissues. Meanwhile, the respiratory system brings oxygen into the body and expels carbon dioxide, facilitating the gas exchange essential for cellular respiration, which provides energy for bodily functions.

7. Similarities and Differences in Plant and Animal Cells: Both plant and animal cells share similarities such as having a nucleus, cytoplasm, and cell membrane, allowing them to perform essential life functions. However, they also have key differences; plant cells possess a rigid cell wall made of cellulose that provides structural support, whereas animal cells lack this feature and have a flexible shape. Additionally, plant cells contain chloroplasts for photosynthesis, enabling them to convert sunlight into energy, while animal cells do not have chloroplasts and rely on consumed organic materials for energy.