Principles Of Organisation
Overview
A single cell can get everything it needs straight through its surface. Make an organism out of billions of cells and that stops working: the cell in the middle is a long way from the outside world. Large organisms solved this by building levels of organisation, and by dedicating whole structures to exchanging materials with the surroundings.
In this lesson you will follow the ladder from cell to tissue to organ to organ system, and see why each rung exists. You will meet differentiation, the process by which cells that start out identical take on different jobs, and you will get a feel for the sizes involved, which is what turns this from vocabulary into understanding.
Objectives
- Large multicellular organisms develop systems for exchanging materials. During the development of a multicellular organism, cells differentiate so that they can perform different functions.
- A tissue is a group of cells with similar structure and function.
- Organs are made of tissues. One organ may contain several tissues.
- Organ systems are groups of organs that perform a particular function. Students should develop an understanding of size and scale in relation to cells, tissues, organs and systems.
Mind map
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Lesson Note
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Lesson Evaluation
Congratulations on completing the lesson on Principles Of Organisation. Now that youve explored the key concepts and ideas, its time to put your knowledge to the test. This section offers a variety of practice questions designed to reinforce your understanding and help you gauge your grasp of the material.
You will encounter a mix of question types, including multiple-choice questions, short answer questions, and essay questions. Each question is thoughtfully crafted to assess different aspects of your knowledge and critical thinking skills.
Use this evaluation section as an opportunity to reinforce your understanding of the topic and to identify any areas where you may need additional study. Don't be discouraged by any challenges you encounter; instead, view them as opportunities for growth and improvement.
- What is a tissue? A. A group of organs working together B. A group of cells with similar structure and function C. A structure made of several different tissues D. A single specialised cell Answer: B
- Which of these is an organ system? A. The stomach B. Muscular tissue C. The digestive system D. A gland cell Answer: C
- What happens during differentiation? A. Cells divide to produce identical copies B. Cells become specialised to perform different functions C. Cells lose their genetic material D. Cells increase in number only Answer: B
- Why do large multicellular organisms need exchange surfaces? A. Their cells do not respire B. Their surface area to volume ratio is too small C. Their cells are larger than those of small organisms D. They contain fewer types of tissue Answer: B
- How many micrometres are there in one millimetre? A. 10 B. 100 C. 1000 D. 10000 Answer: C
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