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Cell Structure - Organelles

Cell Wall

Function

Cell walls support plant cells as their primary function.

Description

Cells in plants are surrounded by a rigid structure, consisting primarily of cellulose or chitin.

Location

Found in the majority of plant cells, fungi, algae, and bacteria and a few archaea.

Found surrounding the cell below the plasma membrane.

Centriole

Function

Centrioles are responsible for chromosomal division during cell division.

Description

Hollow, small that are formed from microtubules.

Microtubules are tiny protein cylinders.

Location

Found in only some plant cells, but is present in animal cells.

Chloroplast

Function

The chloroplasts are the site of photosynthesis.

Description

Chloroplasts are small structures that are flattened. They are encompassed by a double membrane (they also contain other membranes within them called thylakoid membranes).

Location

Found in plant cells.

Cilia

Function

The cilia contain microtubules that allow them to move, which aids in the movement of substances along the cell surface.

Description

The cilia are small, hairlike projections that are formed from nine pairs of microtubules that create a ring, and a single pair of microtubules within the middle of that ring.

Location

Found on the surface of some animal cells.

Flagellum

Function

The flagellum contains microtubules that help it move through contracting, allowing the cell to move.

Description

Similar to cilia as they are formed by a ring of nine pairs of microtubules, with a pair in the middle of the ring.

Location

Found in eukaryotic cells on the surface are surrounded by the plasma membrane.

Golgi Apparatus

Function

The function of the golgi apparatus is to process new lipids and proteins, and package them. The golgi apparatus also creates lysosomes,

Description

The golgi apparatus are a group of flattened, membrane-bound, fluid filled sacs that often are sound with vesicles around their edges.

Location

Found near the nucleus in eukaryotic cells.

Lysosome

Function

The purpose of the lysosome is to digest foreign cells, which is why it contains digestive enzymes.

Description

The lysosome is an organelle that is round and surrounded by a membrane. It also has no clear internal structure.

Location

Found in eukaryotic cells.

Mitochondrion

Function

The mitochondria is the site of aerobic respiration. They are found in large quantities in cells that are more active.

Description

Mitochondria are usually oval in shape and are surrounded by a double membrane; the inner membrane is folded to create cristae. The area inside the mitochondria is called the matrix, which contains the enzymes necessary for respiration.

Location

Found in the cytoplasm.

Nucleus

Function

The purpose of the nucleus is to control transcription of DNA, allowing it to control the cell’s activities. The DNA aids in making proteins as it contains the instructions to create them.

The nucleus also allows the movement of substances between the cytoplasm and the nucleus.

Another function of the nucleus is to make ribosomes.

Description

The nucleus is a large organelle that is encompassed by a double membrane known as the nuclear envelope. The nuclear envelope contains many small pores. The nucleus also contains chromatin, which is formed from proteins and DNA, and sometimes contains a structure named the nucleolus.

Location

Found in the middle of eukaryotic cells.

Plasma Membrane

Function

The purpose of the plasma membrane is to control what enters and exits the cell. The plasma membrane has receptor molecules which helps it respond to hormones and other chemicals.

Description

The plasma membrane is formed from proteins and lipids.

Location

The plasma membrane is the membrane that is found inside the cell wall of prokaryotic cells and plant cells. It is also found on the surface of animal cells.

Ribosome

Function

The ribosomes are the site of protein synthesis.

Description

The ribosome is a tiny organelle that is formed from RNA and proteins and is not surrounded by a membrane.

Location

The ribosome is either found floating freely in the cytoplasm or on the surface of the rough endoplasmic reticulum.

Rough Endoplasmic Reticulum

Function

The purpose of the rough endoplasmic reticulum is to process and fold proteins.

Description

The endoplasmic reticulum is an organelle that contains a fluid-filled space, and has ribosomes covering its surface.

Location

Found in eukaryotic cells.

Smooth Endoplasmic Reticulum

Function

The purpose of the smooth endoplasmic reticulum is to process and synthesise lipids.

Description

The structure of the smooth endoplasmic reticulum is similar to the structure of the rough endoplasmic reticulum, however it doesn't have any ribosomes.

Location

Found in eukaryotic cells.

Vesicle

Function

The purpose of the vesicles is to transport substances into and out of the cell through the plasma membrane, and in between the organelles.

The vesicles are either formed at the cell surface, by the golgi apparatus or by the endoplasmic reticulum.

Description

The vesicle is a small sac filled with fluid that is surrounded by a membrane.

Location

Found in the cytoplasm.

Cell Structure - Organelles

Cell Wall

Function

Cell walls support plant cells as their primary function.

Description

Cells in plants are surrounded by a rigid structure, consisting primarily of cellulose or chitin.

Location

Found in the majority of plant cells, fungi, algae, and bacteria and a few archaea.

Found surrounding the cell below the plasma membrane.

Centriole

Function

Centrioles are responsible for chromosomal division during cell division.

Description

Hollow, small that are formed from microtubules.

Microtubules are tiny protein cylinders.

Location

Found in only some plant cells, but is present in animal cells.

Chloroplast

Function

The chloroplasts are the site of photosynthesis.

Description

Chloroplasts are small structures that are flattened. They are encompassed by a double membrane (they also contain other membranes within them called thylakoid membranes).

Location

Found in plant cells.

Cilia

Function

The cilia contain microtubules that allow them to move, which aids in the movement of substances along the cell surface.

Description

The cilia are small, hairlike projections that are formed from nine pairs of microtubules that create a ring, and a single pair of microtubules within the middle of that ring.

Location

Found on the surface of some animal cells.

Flagellum

Function

The flagellum contains microtubules that help it move through contracting, allowing the cell to move.

Description

Similar to cilia as they are formed by a ring of nine pairs of microtubules, with a pair in the middle of the ring.

Location

Found in eukaryotic cells on the surface are surrounded by the plasma membrane.

Golgi Apparatus

Function

The function of the golgi apparatus is to process new lipids and proteins, and package them. The golgi apparatus also creates lysosomes,

Description

The golgi apparatus are a group of flattened, membrane-bound, fluid filled sacs that often are sound with vesicles around their edges.

Location

Found near the nucleus in eukaryotic cells.

Lysosome

Function

The purpose of the lysosome is to digest foreign cells, which is why it contains digestive enzymes.

Description

The lysosome is an organelle that is round and surrounded by a membrane. It also has no clear internal structure.

Location

Found in eukaryotic cells.

Mitochondrion

Function

The mitochondria is the site of aerobic respiration. They are found in large quantities in cells that are more active.

Description

Mitochondria are usually oval in shape and are surrounded by a double membrane; the inner membrane is folded to create cristae. The area inside the mitochondria is called the matrix, which contains the enzymes necessary for respiration.

Location

Found in the cytoplasm.

Nucleus

Function

The purpose of the nucleus is to control transcription of DNA, allowing it to control the cell’s activities. The DNA aids in making proteins as it contains the instructions to create them.

The nucleus also allows the movement of substances between the cytoplasm and the nucleus.

Another function of the nucleus is to make ribosomes.

Description

The nucleus is a large organelle that is encompassed by a double membrane known as the nuclear envelope. The nuclear envelope contains many small pores. The nucleus also contains chromatin, which is formed from proteins and DNA, and sometimes contains a structure named the nucleolus.

Location

Found in the middle of eukaryotic cells.

Plasma Membrane

Function

The purpose of the plasma membrane is to control what enters and exits the cell. The plasma membrane has receptor molecules which helps it respond to hormones and other chemicals.

Description

The plasma membrane is formed from proteins and lipids.

Location

The plasma membrane is the membrane that is found inside the cell wall of prokaryotic cells and plant cells. It is also found on the surface of animal cells.

Ribosome

Function

The ribosomes are the site of protein synthesis.

Description

The ribosome is a tiny organelle that is formed from RNA and proteins and is not surrounded by a membrane.

Location

The ribosome is either found floating freely in the cytoplasm or on the surface of the rough endoplasmic reticulum.

Rough Endoplasmic Reticulum

Function

The purpose of the rough endoplasmic reticulum is to process and fold proteins.

Description

The endoplasmic reticulum is an organelle that contains a fluid-filled space, and has ribosomes covering its surface.

Location

Found in eukaryotic cells.

Smooth Endoplasmic Reticulum

Function

The purpose of the smooth endoplasmic reticulum is to process and synthesise lipids.

Description

The structure of the smooth endoplasmic reticulum is similar to the structure of the rough endoplasmic reticulum, however it doesn't have any ribosomes.

Location

Found in eukaryotic cells.

Vesicle

Function

The purpose of the vesicles is to transport substances into and out of the cell through the plasma membrane, and in between the organelles.

The vesicles are either formed at the cell surface, by the golgi apparatus or by the endoplasmic reticulum.

Description

The vesicle is a small sac filled with fluid that is surrounded by a membrane.

Location

Found in the cytoplasm.

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