Eukaryotic Cells And Organelles Flashcards
What are the 2 main types of organism?
Eukaryotes and prokaryotes
What are prokaryotic organisms made up of?
Prokaryotic cells
What are eukaryotic organisms made up of?
Eukaryotic cells
What do both types of cells contain?
Organelles
What is the difference between eukaryotic cells and prokaryotic cells?
Eukaryotic cells are more complex
Prokaryotic cells are smaller and simpler
What are organelles?
Parts of cells
What does each organelle have?
A specific function
4 examples of eukaryotic cells?
Animal, plant, algal and fungal cells
What organelles are found in a plant cell but not in an animal cell?
Cellulose cell wall
Vacuole
Chloroplasts
What is the similarity of algal and plant cells?
Carry out photosynthesis
What is the difference between algal cells and plants?
Algal cells can be unicellular or multicellular
What can be different about the chloroplasts in algal cells and plant cells?
In algal cells, chloroplasts can have a different size and shape to a plant
What can fungal cells be?
Unicellular or multicellular
What are the 2 differences between fungal cells and plant cells?
In fungal cells, cell walls are made of chitin, not cellulose
Fungal cells don’t have chloroplasts
Why don’t fungal cells have chloroplasts?
They don’t photosynthesise
What is the cell-surface membrane also called?
The plasma membrane
What is the cell-surface membrane?
Membrane found on the surface of animal cells and just inside the cell wall of other cells
What is the cell-surface membrane made mainly of?
Lipids and protein
What is the function of the cell-surface membrane?
Regulates the movement of substances into and out of the cell
Why does the cell-surface membrane have receptor molecules on it?
So it can respond to chemicals like hormones
What is a nucleus?
A large organelle surrounded by a nuclear envelope which contains many pores
What does the nucleus contain?
Chromosomes and one or more structures called a nucleolus
What is the function of the nucleus?
Controls the cell’s activities by controlling the transcription of DNA
What does the DNA in the nucleus contain?
Instructions to make proteins
What do the pores on the nuclear envelope do?
Allow substances to move between the nucleus and the cytoplasm
What does the nucleolus make?
Ribosomes
What is the structure of a mitochondrion?
Usually oval-shaped
Have a double membrane
Explain the double membrane of a mitochondrion?
Inner one is folded to form structures called cristae
Inside is the matrix, which contains enzymes involved in respiration
What is the function of a mitochondrion?
Site of aerobic respiration
What does aerobic respiration produce?
ATP
Where are mitochondria found in large numbers?
In cells that are very active and require a lot of energy
What is a chloroplast and where is it found?
Small, flattened structure
Plant and algal cells
What is the structure of a chloroplast?
Surrounded by a double membrane and also has membrane inside called thylakoid membrane
These mebranes are stacked up in some parts of the chloroplast to form grana
Grana are linked together by lamellae
What are lamellae?
Thin, flat pieces of thylakoid membrane
What is the function of a chloroplast?
Site where photosynthesis takes place
What are the Golgi apparatus?
A group of fluid-filled membrane-bound flattened sacs
Where are Golgi vesicles usually seen?
Edges of sacs
What is the function of the Golgi apparatus?
Processes and packages new lipids and proteins
Also makes lysosomes
What is a Golgi vesicle?
A smalll fluid-filled sac in the cytoplasm, surrounded by a membrane and produced by the Golgi apparatus
What is the function of the Golgi vesicle?
Stores lipids and proteins made bu the Golgi apparatus and transports them out of the cell
What is a lysosome?
A round organelle surrounded by a membrane, with no clear internal structure
A type of Golgi vesicle
What does a lysosome contain?
What happens?
Digestive enzymes called lysozymes
These are kept separate from the cytoplasm by the surrounding membrane and can be useful to digest invading cells or to break down worn out components of the cell
What is a ribosome?
A very small organelle that floats free in the cytoplasm or is attached to the rough endoplasmic reticulum
What is a ribosome made up of?
Proteins and RNA
Is a ribosome surrounded by a membrane?
No
What is the function of a ribosome?
Site where proteins are made
What is the rough endoplasmic reticulum?
A system of membranes enclosing a fluid-filled space
What is the surface of the rough endoplasmic reticulum covered in?
Ribosomes
What is the function of the rough endoplasmic reticulum?
Folds and processes proteins that have been made at the ribosomes
What is the smooth endoplasmic reticulum?
Similar to rough endoplasmic reticulum but with no ribosomes
What is the function of smooth endoplasmic reticulum?
Synthesises and processes lipids
What is the cell wall?
A rigid structure that surrounds cells in plants, algae and fungi
What is the function of the cell wall?
Supports cells and prevents them from changing shape
What is the cell vacuole?
A membrane-bound organelle found in the cytoplasm
What does a cell vacuole contain?
Cell sap (a weak solution of sugar and salts)
What is the surrounding membrane of a vacuole called?
Tonoplast
What is the function of a vacuole?
Helps to maintain pressure inside the cell and keep the cell rigid
This stops plants wilting
Also involved in the isolation of unwanted chemicals inside the cell
In multicellular eukaryotic organisms, what happens to the cells?
Why?
Become specialised
To carry out specific functions
Why do sperm cells contain a lot of mitochondria?
To provide large amounts of energy needed to propel themselves towards an egg
In multicellular eukaryotic organisms, what do specialised cells that are grouped together form?
Tissues
What is a tissue?
A group of cells working together to perform a particular function
What do different tissues that work together form?
Organs
