Eukaryotic Cell Structure Flashcards
Describe the structure of the nucleus
Surrounded by a nuclear envelope(double membrane) which contains nuclear pores which allow the passage of large molecules such as rna to pass out of the nucleus.
Nucleoplasm which makes up the bulk of the nucleus ( jelly like material)
Chromosome consists of protein bound linear dna
The nucleolus it manufactures ribosomal rna and assembles ribosomes
What are the functions of the nucleus
To control the cells activities ( transcription of dna)
Retain genetic material of the cell in the from dna and chromosomes
Manufacture ribosomal rna and ribosomes
Describe the structure of the mitochondrion
They have a double membrane, inner one is folded to form structures called Cristae(large sa), inside is the matrix which contains enzymes involved in respiration
What is the mitochondrion function?
Site of aerobic respiration where atp is produced
Found in large numbers in cells that are very active and require a lot of energy
Describe the structure of the chloroplasts
Surrounded by a double membrane (highly selective in what enter and leaves )
Grana are stacks of disc like structures called thylakoids. Within the thylakoids are chlorophyll. Grana are linked together by lamellae
Function of chloroplasts
Site where photosynthesis takes place.
Grana membranes has provide a large SA
Describe the structure of the rough endoplasmic reticulum
A system of membranes enclosing a fluid filled space, surface is covered in ribosomes
Rough endoplasmic reticulum function
Provides large SA for the synthesis of proteins and glycoproteins
Provide a pathway for the transport of materials, especially proteins, throughout the cell
Smooth endoplasmic reticulum structure
Similar to RER but has no ribosomes
Smooth endoplasmic reticulum function
Synthesise, store and transport lipids and carbohydrates
Golgi apparatus structure
A group of fluid filled, membrane bound flattened sacs. Vesicles are often seen on the edge of the sacs
Golgi apparatus function
Transport, modify and store lipids
Form lysosomes
Add carbohydrate to proteins from glycoproteins
Produced secretory enzymes
Secrete carbohydrates
Golgi vesicles structure
A small fluid filled sac in the cytoplasm, surrounded by a membrane and produced by the Golgi apparatus
Golgi vesicles function
Store lipids and proteins made by the Golgi apparatus and transports them out of the cell
Lysosomes structure
Surrounded by a membrane, no clear internal structure (type of Golgi vesicles)
Lysosomes function
Contain digestive enzymes called lysozymes, can be used to digest invading cells or to break down worn out components of cells
Also
Hydrolyse material ingested by phagocytic cells
Release enzymes to the outside of the cell to destroy material around the cell
Digest worn out organelles so that the useful chemicals they are made of can be re used
Completely break down cells after they die
Ribosomes structure
Very small organelle, made up or proteins and rna and not surrounded by a membrane
Ribosomes function
The site of protein synthesis
What are the 2 types of ribosomes
80s found in eukaryotic cells
70s found in prokaryotic cells
Cell wall structure
Rigid structure ( made of carbohydrate cellulose)
In fungi (chitin)
Microfibrils in cellulose Help strengthen the wall
Cells wall function
Supports cells and prevents them from changing shape
Vacuole structure
A membrane bound organelle
Contains cell Sap- weak solution of sugar and salts
Surrounding membrane is called tonoplast
Cell membrane structure
Made mainly of lipids and proteins
Cell membrane function
Regulates movement of substances in and out of cells
