The Cell (CH1 SEG1)

Cell

it's considered the basic unit of all organisms.

All living things are made up of a cell or cells.

It is the structural and functional unit of organisms.

It has the ability to self-reproduction from previously existing cells.

What are the two types of cells?

1. prokaryotic cell: such as bacteria. lacks nuclear membrane and membranous organelles

2. eukaryotic cell: larger than the prokaryotic cell, has nuclear nycleus and is surrounded by a nuclear membrane and cell organelles

Explain what you know about developments in cell study

1. The cell was not known when theGerman scientist Antoine Van Leeuwenhoek (1632 - 1723) invented the microscope. He could be the first who saw the cell

2. The 🏴󠁧󠁢󠁥󠁮󠁧󠁿 English scientist Robert Hooke (1635 - 1703) had the same observations of Leeuwenhook, and was the first to use the word “cell” when he examined the structure of an oak tree cortex. He described corky units and defined the cell as an aerobic chambers similar to a bee hive.

3. The 🏴󠁧󠁢󠁳󠁣󠁴󠁿 Scottish scientist Robert Brown discovered the nucleus of the cell in 1831 and decribed it.

4. The 🇩🇪 German scientist Mathias Schleiden concluded that all plants consist of cells in 1838

5. The 🇩🇪 German scientist Theodor Schwann concluded that all animals consist of cells in 1839

Studies and researched into cytology have increased, particularly after advances in … and the invention of …

The study has become a major branch called …

the light microscope, the electron microscope, cytology

Cytology

It's one of the branches of biology concerned in the study of cells.

What is cell theory based on/are the bases of cell theory? Define Cell theory

It's one of the branches of biology concerned in the study of cells.

The scientists … and … are the ones who described the cell theory.

Matthias Schleiden, Thomas Schwann

How does cell vary in size? explain

1. some cells can be seen with the naked eye, such as a frog's egg (1 mm)

2. small cells that are not visible to the naked eye, such as a human's egg (100 μm or less)

3. most cells are smaller than 1 mm, and there are cells less than 100 μm

Do cells have specific specialties?

Cells have specific specialties to increase the efficiency of various functions.

We need a microscope to see cells and microorganisms. Cells can be seen with light microscope, but inner components of the cell like organelles, viruses and organic particles can only be seen with a light microscope.

Explain the Prokaryotic cell

1. it is an undeveloped cell; it is more primitive in shape and structure.

2. it has a genetic material without a membrane caled the nuclear zone or nucleoid

3. its cytoplasm has no membranous organelles like Golgi bodies or mitochondria. it has ribosomes in the form of numerous small grains, which build proteins

4. it's represented by blue-green algae, bacteria and mycoplasma which all belong to the Monera kingdom

What does the bacterial cell consist of? or explain the structure of the bacterial cell

1. each bacterial cell represents a prokaryotic organim. it is surrounded by a solid wall consisting of chemical compounds (protein, lipids, and polysaccharides)

2. behind that wall, there is a plasma membrane (semi-fluid membrane) that surrouds the cytoplasm

3. the cyctoplasm contains the nucleoid. there are no nuclei or nuclear envelope, unlike eukaryotic cells and ribosomes

4. some typesbof moving bacteria have flagella, pili or both

Draw the structure of bacteria

List the general appearance of bacteria cell

• Cell covering: (1) cell wall (2) plasma membrane

• Cytoplasm: (1) nucleoid (2) ribosome

• Suffixes: (1) flagella (2) fimbriae (3) sex pili

Why are prokaryotic cells considered undeveloped?

It is an undeveloped cell that is more primitive in shape and structure

Why can bacteria and blue-green algae build protein?

because it contains a large number of ribosomes in the cytoplasm that builds proteins in the cell

Why does bacteria (blue-green algae) have a nuclear zone? [image unrelated]

Because it has a nucleus without a nuclear envelope/membrane

Why does bacteria differ from blue-green algae?

1. bacteria has no chlorophyll pigment

2. bacteria cell wall is surrounded by a capsule, while blue green algae cell wall is surrounded by a gelatin membrane

• What is the chemical structure of prokaryotic/bacterial cell wall?

The cell is surrounded by a solid wall consisting of the following chemical compounds:

• Protein

• Lipids

• Polysaccharides [poly + nerdy term for sugar in arabic]

Explain eukaryotic cell

This cell has true nucleus and is found in Protists, Fungi, Plants and Animals.

Some of these cells have varying shapes; they change from time to time (like amoeba), while some are sphereical, pyramidal, oval, tubular, cubic, flat, astral, fusiform, etc. (in a fixed shape)

They're small and csn only be seen by microscope, but they are larger than prokaryotic cells.

Why is there a difference in the shape of eukaryotic cells?

Such change in shape is due to function of these cells, because cells often have shapes that adapt their function.

Generally, cells need a surface area (plasma membrane)

To exchange materials with the surrounding environment appropriately

Compare between Prokaryotic and Eukaryotic cells

1. They are represented by bacteria, blue-green algae and mycoplasma which all belong in the Monera kingdom. They are found in fungi, protist, plants and animals.

2. They have a nucleus without a nuclear membrane called the nuclear zone. They have a true nucleus surrounded by a nuclear membrane

3. The cytoplasm doesnt contsin membranous organelles, like mitochondria and others. The cytoplasm contains membranous organelles such as mitochondria and others

4. Undeveloped. More developed than prokaryotic cells

5. Smaller than eukaryotic. Larger than prokaryotic

6. They have a cell wall and plasma membrane. The plant cell has a cell wall and plasma membrane, and the animal only has a plasma membrane.