3.4 Structure of Eukaryotic Cells Flashcards
What is the function of chloroplast
Contain two (outer and inner) fluid separated membranes; the inner membrane is folded into a network of flattened sacs called thylakoids
Thylakoids are stacked into Granum
Thylakoids contain chlorophyll where the process of photosynthesis occurs
What is the function of Lysosomes?
Round organelles hat are surrounded by a membrane with no clear internal structure
Contain digestive enzymes and are kept separate from the cytoplasm by the surrounding membrane
Can be used to digest invading cells or break down worn out components of the cell.
What is the function of the Cell Wall?
It helps to support and protect the plant
It is permeable so has no effect on the movement of molecules in or out of the cell
In plants it is made of rigid cellulose fibres
In fungi it is made of chitin
What is the function of Ribosomes?
Used for protein synthesis - works by reading triplet codons and stringing amino acids together
mRNA, tRNA
very small organelles that float freely in the cytoplasm or are attached to the rough endoplasmic reticulum
What is the function of Endoplasmic Reticulum?
System of membranes with rough ER being covered in ribosomes
Smooth ER synthesised and processes lipids
Rough ER folds and processes proteins that have been made by ribosomes
What is the function of the Vacuole?
Membrane bound organelles that have no specific shape
Contain water with different compounds in them
Formed by the joining together of many vesicles
Important in plant cells for maintaining turgor or pressure(keeping the cells shape)
What is the function of the Golgi apparatus?
Golgi apparatus are a group of fluid filled flattened sacs
They process and package lipids and proteins
These proteins are transported elsewhere by Golgi vesicles (membrane-bound sacs)
Also make lysosomes
What is the function of the Mitochondria?
Have a double membrane; the inner membrane is folded to form membranes called cristae
inside is the matrix(liquid) which contains enzymes for aerobic respiration which releases ATP(common energy source of the cell)
Found in large numbers in cells that are very active and need lots of energy.
What is the function of the Plasma Membrane?
Regulates the movement of substances in and out.
Has receptor molecules on it, which allows it to respond to chemicals like hormones
(made mainly of lipids and protein)
(on the surface of animal cells, inside the cell wall of prokaryote and plant cells)
What is the function of the Nucleus?
Large organelle surrounded by a nuclear envelope (double membrane) which contains many pores
contains chromatin and a structure called the nucleolus
Chromatin is made from proteins and DNA (DNA control the cells activities)
The pores allow substances to move between the nucleus and the cytoplasm
nucleolus makes ribosomes
