Ultrastructure of the cell Flashcards
Describe the Centriole,
Small, hollow cylinders made of microtubules, 2 bundles of microtubules at right angles to each over
What are microtubules?
Small protein cylinders
What is the function of the Centriole?
Assists with the separation of chromosomes.
Describe the Cilia.
small, hair-like structures.
What does the cross section of cilia look like?
outer ring membrane with a ring of 9 pairs of protein microtubules inside, with 2 in the middle.
What is the function of the cilia?
To move substances along the cell surface.
Describe the Rough Endoplasmic Reticulum (RER).
System of fluid filled cavities enclosed by membrane with the surface covered with ribosomes.
What is the function of the Rough Endoplasmic Reticulum (RER)
Transports proteins made by the ribosomes.
Describe the Smooth Endoplasmic Reticulum (SER)
System of fluid filled cavaties enclosed by a membrane.
What is the function of the Smooth Endoplasmic Reticulum?
To synthesize and process lipids
Describe a vesicle.
Small fluid filled sac surrounded by a membraine.
What is the function of a vesicle?
To transport substances in and out of the cell and between different organelles.
Describe the Golgi Apparatus / body
A group of fluid filled membrane bound flattened sacs.
What is the function of the Golgi Apparatus / body?
To process and package new lipids and proteins and make lysosomes.
Describe a Mitochondrion.
Oval shaped, with a double membrane of which the inner is folded to form the cristae. In the center is the matrix with enzymes.
What is the function of mitochondrion?
Site of aerobic respiration and where ATP is produced.
Where would you find lots of mitochondria?
In very active cells that require a lot of energy.
Name the 4 structures in a chloroplast.
Stroma, Granum, Double membrane and lamella
Describe a chloroplast.
Flattened structure surrounded by a double membrane with an membrane inside called thylakoid membranes. These are stacked to form Grana which is linked by Lamella.
What membrane is stacked to make a Granum?
Thylakoid membrane
What mostly makes up the plasma membrane
Lipids and proteins
What is on the outside of the nucleus
The nuclear envelope
What is the function of the plasma membrane?
To regulate the movement of substances and respond to hormone with receptor molecules.
Describe the nucleus
Large organelle surrounded by a nuclear envelope containing pores. The nucleus contains chromatin and a structure called the nucleolus.
What is in the center of the nucleus?
Chromatin and the nucleolus
What makes up chromatin?
DNA and proteins
What is the function of the nucleolus
Making ribosomes
Describe a lysosome.
Round organelle surrounded by membrane
What do lysosomes contain?
Powerful digestive enzymes
What do the enzymes in lysosomes do?
Digest invading cells and break down worn out components of the cell.
Where would you find ribosomes?
Floating free in the cytoplasm or connected to the rough endoplasmic reticulum.
What is the function of ribosomes?
Synthisise proteins
Where are new proteins transported to from the rough ER
The golgi apparatus
How are proteins threads arranged in Eukaryotic cells?
As Microfilaments and Microtubules
How would you describe the cytoskeleton?
As a network of protein threads.
What is the cytoskeletons 4 main functions?
-Support organelles and keep them in position.
-Strengthen the cell and maintain its shape.
-Move materials in the cell such as chromosomes in division.
-Cause the cell to move by moving flagella and cilia.
What are microfilaments?
Small solid strands of protein.
What shape is DNA in prokaryotes?
circular
What shape is DNA in eukaryotes?
Linear
What is the cell wall made of in prokaryotes?
polysaccharide but not cellulose or chitin
What makes up the cell wall in fungi?
Chitin
What makes up the cell wall in plant cells?
Cellulose
What makes a flagella in prokaryotes?
The protein flagellin arranged in a helix
What makes up a flagella in eukaryotes
microtubule proteins arranged in a 9 + 2 formation
What does the stain methylene blue stain and what colour is produced?
stains living cells a dark blue and substances such as chromatin
What does iodine stain and what colour is produced?
stains living plant cells a very dark blue
what does acidified phloroglucinol stain and what colour is produced?
stains lignin cells (wall of xylem) a bright red
what does acetic orcein stain and what colour is produced?
Stains nuclei and chromosomes a red
What does eosin stain and what colour is produced?
Stains some organelles and cytoplasm a pink colour
Structures or organelles
What does light green stain and what colour is produced?
stains plant cell walls a green.
