24. Mitochondria Flashcards
Mitochondria
What is the main functions of mitochondria?
Structure:
What is the shape of mitochondria? What is the size in width and length? Is it membranous?
Number:
How many mitochondria are there in a cell? Fibroblasts? Hepatocytes? Oocytes?
The main function of mitochondria is ATP and steroid synthesis.
The shape of mitochondria is round or oval. The width is 0,5 to 1 micrometer and the length can be up to 10 micrometers. The Mitochondria is membranous it has a double membrane the inner and outer membrane.
The number of mitochondria in a cell varies depending of the cells function and demand of of mitochondria. Fibroblasts have around 100 mitochondria. Hepatocytes have around 800 mitochondria. Oocytes have around 300thousand mitochondria.
Outer membrane
What are its biggest components? What is the transport protein called? What kind I’m enzymes does the outer membrane have?
Inner membrane
What are its biggest components? What kind of enzymes does it have? What are the enzymes utilised for? What kind of tubules does it form and what for? What kind of particles is attached to it?
Structures attached to the inner membrane
What’s the spherical structure attached to the inner membrane called? What does the spherical shape of it resemble?
Outer membrane
The biggest components of the outer membrane is lipids and proteins which compose 50% of the the other membrane. Its transport protein is called porins. The enzymes are oxidases, hydrolases, transferases, enzymes of fatty acid metabolism and cytochromes.
Inner membrane
The biggest components of the inner membrane is proteins and cardiolipins which compose 80% of the membrane. It has reductases, oxidases, dehydrogenases, ATP synthase, transferase and cytochromes. The enzymes are utilised for oxidative phosphorylation and for the electron transport system. It forms cristae that are used to form the intracristal space. It is attached to elementary particles.
Structures attached to the inner membrane
The spherical structure attached to the inner membrane is called oxisomes or ATPsomes because it contains ATP synthase activity. It’s spherical shape resembles a tennis racket.
What is the space between the membranes called? What is the interior part of the mitochondria called?
Mitochondrial matrix
What is the mitochondrial matrix rich in? What kind of granules does it have and what kind of ions do they storage? What kinds of RNAs does it have? Does it have DNA? In what shape? Does it have polymerases? What is it needed for? What does it also have enzymes for?
The space between the membranes is called intramembranous space. The interior part of the mitochondria is called the intercristal space.
The mitochondrial matrix is rich in protein, DNA and RNA. It has matrix granules that are storage sites for calcium and magnesium ions. It has mitoribosomes(mrRNA), mitochondrial mRNA and tRNA. It has DNA that is in circular shape in the matrix. It has polymerases that is needed for the synthesis of DNA and RNA. It also has enzymes for Krebs cycle, protein synthesis and lipid synthesis.
Origin
What is often brought up on the origin of mitochondria? Where is the new mitochondria believed to be derived from and how? What does it have the components for?
The mitochondria is believed to once have been a free living cell just by itself. The new mitochondria is believed to be derived form the pre existing mitochondria by growth and division.
