Cell Organelles Flashcards
What does the nucleus contain?
Nucleolus, nucleoplasm, nuclear envelope, chromatin and nuclear pores
What’s the structure of a nucleus?
- largest organelle
- spherical
- dark patches = chromatin (made from protein and DNA)
- surrounded by the nuclear envelope
- composed of 2 membranes
- has nuclear pore - allows certain molecules through
- nucleolus inside - makes rRNA and ribosomes
- nucleoplasm - jelly like substance
What’s the function of a nucleus?
- contains genetic material in the form of DNA / chromosomes
- chromatin consists of DNA & history proteins (A histone is a protein that provides structural support for a chromosome.)
- contains instructions for making proteins by producing mRNA
- manufacture rRNA and ribosomes
What does the structure of rough Endoplasmic reticulum have
- system of membranes enclosing a fluid filled space
- has ribosomes on the outer surface
- has a large surface area
What is the function of the rough Endoplasmic reticulum?
- synthesis of proteins and glycoproteins
- provides a pathway for materials to be transported throughout the cell especially proteins
What’s the structure of the smooth Endoplasmic reticulum?
- system of membranes enclosing a fluid filled space
- large surface area
Whats the function of the smooth Endoplasmic reticulum?
- synthesis
- storage
- transport of lipids and carbohydrates
What is the structure of the Golgi apparatus?
- stack of membrane-bound flattened sacs
What is the function of the Golgi apparatus?
- modifies and packages proteins
- adds carbohydrates to proteins to form glycoproteins
- produces secretory enzymes
- forms lysosomes
What is the structure of ribosomes?
- 2 sub units (small sub unit ad large sub unit)
- contains ribosomal RNA & protein
- floats freely in the cytoplasm or attached to the membrane of rough Endoplasmic reticulum
- not surrounded by a membrane
What is the function of ribosomes?
- protein synthesis
2 types of ribosomes:
- 80S (eukaryotic cells, 25nm in diameter)
- 70S (prokaryotic cells)
What is the structure of mitochondria?
- 2 membranes separated by a fluid filled space
- inner membrane is folded to form Cristal
- central part is the matrix
What is the function of mitochondria?
Site where ATP is produced or energy is release during aerobic respiration
What is the structure of lysosomes?
- ## spherical sacs surrounded by a single membrane
What is the function of lysosomes?
- contains digestive (hydrolytic) enzymes which break down materials
- eg specialised lysosome (acrosome) in head of sperm cells to help it penetrate the egg