SEL. Materi Biologi Kelas Xl SMA. Oleh : Fitri Hariana, STP. SMAN 1 Pantai Labu

Summary

In this biology lesson for 11th grade students, Fitri Haryana introduces the topic of cells. The lesson covers the history of cell discovery, starting with key figures like Robert Hooke, Robert Brown, and others who made groundbreaking contributions. It explores cell theory, emphasizing cells as the smallest structural and functional units of life. The lesson also delves into cell types, explaining prokaryotic and eukaryotic cells, and highlights the chemical components of cells, including biomolecules such as carbohydrates and proteins. The session concludes with an assignment to write about the figures and theories discussed in the lesson.

Takeaways

• 😀 Robert Hooke discovered cells by observing cork slices under a microscope, concluding that cells are empty cavities.
• 😀 Robert Brown discovered the nucleus, naming it as the most important part of a cell, as it regulates all cell activities.
• 😀 Felix Dujardin found cell fluid in living cells and concluded that cell fluid is the most important part of a cell.
• 😀 Johannes Purkinje coined the term 'protoplasm' to describe the living fluid inside cells.
• 😀 Cell theory consists of several ideas: cells are the smallest structural unit, heredity unit, growth unit, and functional unit of living organisms.
• 😀 Gregor Mendel's contributions to cell theory emphasized that cells are the smallest units of heredity that carry genetic traits.
• 😀 Cells are incredibly small, typically ranging from 1-100 micrometers in size, and cannot be seen by the naked eye.
• 😀 There are two types of microscopes: light microscopes, which observe general cell structure, and electron microscopes, which can observe cell organelles.
• 😀 Cells are classified into two types: prokaryotic (without a nucleus) and eukaryotic (with a nucleus).
• 😀 Prokaryotic cells include bacteria and blue algae, while eukaryotic cells make up most other living organisms.
• 😀 Chemical components of cells include biomolecules such as carbohydrates and proteins, which interact to show the characteristics of life.

Q & A

Who was the first person to discover cells and what was their contribution?

The first person to discover cells was Robert Hooke. He observed cork slices under a simple microscope and concluded that cells are empty cavities.

What significant discovery did Robert Brown make in relation to cells?

Robert Brown discovered the cell nucleus. He observed an object floating in the center of the cell and named it the nucleus, emphasizing its importance in regulating cell activities.

What did Felix Dujardin discover about living cells?

Felix Dujardin discovered that living cells contain a fluid substance, which he identified as cell fluid or cytoplasm. He proposed that this fluid is essential for the cell's function.

What term did Johannes Purkinje coin in relation to cell structure?

Johannes Purkinje coined the term 'protoplasm' to describe the living fluid found within the cell.

What is the main idea behind the cell theory proposed by Matthew Schleiden and Theodor Schwann?

Matthew Schleiden and Theodor Schwann proposed that cells are the smallest structural unit of living organisms, meaning all living things are made up of cells.

How did Gregor Mendel contribute to cell theory?

Gregor Mendel, the father of genetics, contributed to cell theory by stating that cells are the smallest unit of heredity, responsible for passing on genetic traits from parents to offspring.

What did Rudolf Virchow propose about the role of cells in the growth of living organisms?

Rudolf Virchow proposed that cells are the smallest unit of growth, forming the foundation for the growth of living organisms.

What does Max Schultze's contribution to cell theory explain?

Max Schultze explained that cells are the smallest functional unit of living organisms, responsible for executing essential life functions such as respiration and reproduction.

What is the main difference between prokaryotic and eukaryotic cells?

Prokaryotic cells do not have a cell nucleus membrane, meaning their genetic material is not enclosed in a nucleus, whereas eukaryotic cells have a cell nucleus membrane that surrounds their genetic material.

Why are cells considered too small to be observed with the naked eye?

Cells are typically between 1-100 micrometers in size, which makes them too small to be seen without the help of a microscope.