Biology 8 Lesson 2: Structure of the human body
1. Summary of theory
a. Body parts
The human body is covered by a layer of skin. There are many small, uneven hairs on the skin. In the skin there are blood vessels, nerve endings and sweat glands. The skin protects the organs in the body from harmful influences of the external environment, contributing to keeping the body temperature constant.
Under the skin is a layer of fat, under the fat layer is muscle and bone. Muscles form the outer shape of the body, and bones form the frame that protects the body and internal organs.
The human body has 3 parts: head, torso and limbs.
There are two largest body cavities, the thoracic cavity and the abdominal cavity. These 2 compartments are located in the body and separated by the diaphragm.
Body cavity containing internal organs:
- Chest cavity contains: heart, lungs, trachea, esophagus.
- The abdominal cavity contains: stomach, intestines, liver, gallbladder, pancreas, spleen, kidneys, bladder, sex organs.
b. Organ systems
– In the body there are many organ systems, but mainly: the motor system, the circulatory system, the respiratory system, the digestive system, the excretory system, the nervous system, the endocrine system and the genitourinary system.
- Muscles and bones
- Movement and movement
- Mouth, alimentary canal, digestive gland
- Transforming food to provide nutrients to the body
- Heart and vascular system
- Transport and exchange nutrients to cells, carry CO2 waste from cells to excretory organs
- Airway, lungs
- Exchanging oxygen and carbon dioxide between the body and the environment.
- Kidneys, ureters and bladder
- Filter blood to make urine
- Brain, medulla, nerves, ganglia
- Regulate, control and coordinate activities of agencies.
– In addition to the above organ systems, the body also has skin, senses, organ systems are the reproductive system to help maintain the breed, the endocrine system to help control and regulate the body’s metabolism by hormones.
1.2. Coordination of movement between agencies
– Body as a unified bloc.
– The organs in the body have a rhythmic coordination, ensuring unity. That unification is achieved by the control of the nervous system (neuromechanism) and by the flow of blood in the circulatory system carrying the hormones secreted by the endocrine glands (the humoral mechanism).
– For example, when running, the locomotor system works with great intensity. At that time, other organ systems also increase activity, the heart beats faster and stronger, blood vessels dilate (circulatory system), breathing fast and deeply (respiratory system), sweating profusely (excretory system), …
The relationship between the agencies can be visualized according to the following diagram:
2. Illustrated exercise
Question 1: How many parts does the human body consist of? What organs does the body consist of?
The human body is divided into three parts: head, trunk and limbs.
The cell body consists of 2 compartments:
- Chest cavity: contains the heart and lungs.
- Abdominal cavity: contains the stomach, intestines, liver, excretory system (kidneys, bladder) and reproductive organs.
Verse 2: How do the cells of the body regularly exchange substances with the external environment?
The cells of the body regularly exchange substances with the external environment through the body’s organ systems:
– Respiratory system and circulatory system: Helps the body exchange gases (02 and C02) between the body and the external environment. Health give 02 from the lungs to the cells and get C02 in cells leading to the respiratory system.
– Digestive system: Helps the body digest food from the external environment and absorb nutrients to perform metabolic processes with cells, and at the same time discharge waste products into the external environment.
– Excretory system: The kidneys filter and excrete urine to the external environment.
– Sweating skin.
Question 3: Give examples and analyze the role of the nervous system in the regulation and coordination of organ systems?
The nervous system is the most highly differentiated organ system in the human body, in the form of tubes and networks throughout the body, made up of a specialized type of tissue called nerve tissue, including nerve cells. – neurons and glial cells (nerves).
– Examples of the role of the nervous system in the coordination of organ systems:
When working or playing sports, the heart beats faster, the breathing rate increases, blood vessels to the muscles dilate, sweat is released… Rest for a while, all the activities of the above organs gradually return to normal.
– All of the above changes are reflexes under the control, regulation and coordination of the nervous system.
– Many similar examples can be given.
3.1. Essay exercises
Question 1: When talking about the organ systems in the body, say:
a) The role of those organ systems.
b) Draw a diagram showing the relationship between the organ systems in the body.
Verse 2: In the human body, which organ is located in the thoracic cavity?
Question 3: In the human body, which organ is located in the abdominal cavity?
Verse 4: What organs are in the respiratory system?
Question 5: Which organ system is distributed in most parts of the body?
3.2. Multiple choice exercises
Question 1: Unity in the body is made possible by
A. Neural Mechanism
B. Mechanism of translation.
C. Endocrine glands
D. Both A and B.
Verse 2: Which organ system is responsible for converting complex organic matter in food into simple organic matter?
A. Digestive system.
B. Respiratory system.
C. Circulatory system.
D. The excretory system.
Question 3: Which organ system is responsible for transporting nutrients to organs in the body?
A. Digestive system. B. Respiratory system.
C. Circulatory system. D. The excretory system.
Verse 4: Which organ system is responsible for reproduction?
A. Genitourinary system. B. Respiratory care.
C. Circulatory system. D. The excretory system.
Question 5: Which of the following organs is part of the excretory system?
A. Kidney. B. Testicles
C. Spinal cord. D. Vagina.
Question 6: Which of the following organs is part of the reproductive system?
D. Both A, B and C.
After studying the lesson human body structure Here you need:
Name and locate organs in the body.
– Explain the role of the nervous and endocrine systems in regulating the functioning of organs.
Describe the organ systems and their roles in the body.