Eukaryotic cells Flashcards
What is a chloroplast?
An oval shape flattened organelle with a double membrane
Inside it has stacks of membrane called thylakoid membrane
This is where chlorophyl is found
Function of chloroplast?
The site of photosynthesis
Chlorophyll absorbs light energy and uses this as energy to synthesise glucose
What is a mitochondrion?
An oval shaped structure organelle with a double membrane
The inner membrane is folded to form structures cristae
The inner fluid compartment is called the matrix
Function of Mitochondrion?
The site of aerobic respiration which produces ATP
The matrix contains the enzymes involved in respiration
What is a golgi apparatus?
A stack of fluid filled membrane bound sacks
Vesicles are often seen at the edges of the sacs
Function of golgi apparatus?
Processes and packages polypeptides (chains of amino acids) for exocytosis (movement of proteins and polysaccharides)
Also processes lipids and forms lysosomes
The vesicles transport the processes proteins and lipids to the cell surface membrane
What is the vacuole?
A membrane bound organelle found in the cytoplasm
It contains cell sap (sugar and salt solution)
Function of permanent vacuole?
Helps maintain pressure to keep the plant cell turgid
Contains a large volume within a plant cell and is flexible
The site of isolation of unwanted chemicals inside the cell
Function of nucleolus?
The site of production of ribosomes
Looks like a nucleus within the nucleus
What is a cell wall?
Surrounds cells in plants, algae and fungi
In plants and algae it is made from cellulose
In fungi it is made from chitin
Function of the cell wall?
Supports the cells and prevents them from losing shape
Allows the cell to become turgid without bursting and withstand pressure
Function of the nucleus?
Controls the cells activities by controlling the transcription of DNA to RNA
What is a nucleus?
A large organelle surrounded by double membrane called the nuclear envelope, which contains many pores
It contains genetic material of the cell and one or more nucleoli
What is a lysosome?
A type of golgi vesicle with a membrane made of phospholipids
Inside the vesicle there are enzymes
Function of a lysosome?
Contains hydrolytic called lysozymes
They can be used to digest invading cells or worn out organelles
What is a cell surface membrane?
A bilayer of lipids with proteins embedded in it
Some of these lipids and proteins have carbohydrates attached to them
Function of cell membrane?
Regulates the movement of substances into and out of the cell
It has receptor molecules on the surface to allow it to respond to chemicals like hormones and cell recognition
Function of cytoplasm?
Gel like fluid where cell organelles are found
Function of nuclear pore?
Small gaps in the nuclear membrane that allow ribosomes, RNA and nucleotides to pass in and out of the nucleus
Function of chromatin?
A complex of macromolecules found in the nucleus consisting of DNA, protein and RNA
What is a ribosome?
They are very small organelles floating freely within the cytoplasm or attached to rough endoplasmic reticulum
They are made up of a small and larger subunit
Made up of proteins and RNA
They are not membrane bound
Function of ribosomes?
Where amino acids are synthesised to form proteins
What is the rough endoplasmic reticulum?
A system of membranes enclosing a fluid filled space creating passageways
The surface is covered in ribosomes
Function of rough endoplasmic reticulum?
Provides a network of membranes for transport of polypeptides (long chain amino acids)
Main site of protein synthesis due to the presence of ribosomes
What is the smooth endoplasmic reticulum?
A system of membranes enclosing a fluid filled space
Function of smooth endoplasmic reticulum?
It is the site of synthesis and processing lipids
Function of centrioles?
Help in the formation of spindle fibres that separate the chromosomes during cell division-mitosis
Function of nuclear membrane/envelope?
Encloses the nucleus encasing the genetic material
Made of lipids
Function of vacuole membrane?
Encloses the vacuole
Can expand rapidly to allow the vacuole more volume to hold fluids and nutrients
The surrounding vacuole membrane is called tonoplast.
Function of plasmodesmata?
A channel through the cell wall that allows molecules and substances to move back and fourth as needed
Allows tissues and organ cells to work together to achieve a common goal
What is a cell?
The smallest structural functional unit of an organism
What is a tissue?
A group/aggregation of similar cells, which carry out a particular function
What is an organ?
An aggregation of different tissues/ cells; carrying out a specific physiological function
What is an organ system?
An aggregation of organs carrying out a specific physiological function more efficiently
What is an organism?
Made up of different organ systems working together
What is a cell that contains a nucleus called?
Eukaryotic cell
