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Biology 2nd Baccalaureate

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1.4. Organs and systems

Organs and systems

Several tissues that collaborate to perform a certain function join to form an organ, such as the stomachheartlung, kidney,... The heart, for example, is an organ made up of different tissues, but with the same function, pump blood throughout the body.

The organs are grouped together forming a system, performing specific functions. It is necessary to clarify that the same organ can intervene in several different systems, such as the lungs, which are part of the respiratory system but also collaborate with the circulatory and excretory systems.

The different systems work in coordination in a set that is the human organism, performing the three vital functions that living beings perform:

Interactive activity: Organs, systems and apparatus.

Interactive activity: Sort by complexity.

Interactive activity: Apparatus and systems.

Interactive activity: Apparatus and systems (2).

Answer in your notebook

1.9.- What are the vital functions of living beings? Reason which one is more important to you.

Systems involved in nutrition function

There are four processes in nutrition that are responsible for four other systems:

  • The digestive process: The digestive system is responsible for incorporating organic matter, making the digestion and absorption of the nutrients contained in food to be able to take advantage of them in the body, and the defecation of unabsorbed substances in the digestive tract .
  • The breathing: The breathing system is responsible for taking the oxygen of the air to the circulatory system to drive the cells, and expel foreign carbon dioxide (CO2) from the cellular metabolism.
  • The excretion: The excretory system removes waste products from cell metabolism, such as urine and sweat. As we have seen, the respiratory system also participates in excretion by expelling CO2 .
  • The circulation: The circulatory system consists of the heartarteries, veins and capillaries, and is responsible for transporting nutrients, oxygen and waste substances, among other functions.
Aparatos que intervienen en la nutrición
Aparatos que intervienen en la nutrición

Systems involved in the reproduction function

The male and female reproductive systems are involved in the function of reproduction, making the survival of the species possible.

Systems involved in the relationship function

The nervous system is responsible for coordinating vital functions and collecting information from stimuli that arrive both from inside and outside of our body to sensory receptors (sense organs). In addition to collecting this information, it processes it, and elaborates a response that transmits it to the effector organs. This response can be secretory (endocrine system) or motor (muscular system and musculoskeletal system).

Interactive activity: Organization of matter in the muscular system and locomotor system.

Interactive activity: The functions of living beings.

Interactive activity: Apparatus and functions.

Answer in your notebook

1.10.- How are the apparatus different from the systems? ( Seen in point 1.1 )

Answer in your notebook

1.11.- Write the name of two organs, two apparatus and two systems.


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Biology and Geology teaching materials for Compulsory Secondary Education (ESO) and Baccalaureate students.