Cell Structure and Division- Eukaryotic Cells and Organelles Flashcards
How do eukaryotic cells compare to prokaryotic cells?
They are complex and include all animal and plant cells, including fungi and algae cells
How are eukaryotic cells the same as prokaryotic cells?
They both contain organelles
What are organelles?
Parts of the cell that each have a specific function
What are the organelles that plant cells have and animal cells don’t have?
A cellulose cell wall with a plasmodesmata, a vacuole and chloroplasts
How are fungal cells different to plant cells?
Cell walls are made of chitin and they don’t have chloroplasts
What is the cell-surface membrane (plasma membrane)?
Found on the surface of animal cells and inside cell wall of other cells, made mostly of lipids and protein
What is the function of the cell-surface membrane?
Regulates the movement of substances into and out of cell, also has receptor molecules to allow it to respond to chemicals like hormones
What is the nucleus?
- A large organelle surrounded by a nuclear envelope which contains nuclear pores
- Contains chromosomes
- Contains one or more nucleolus
What is the function of the nucleus?
- Controls cells activities
- Contains instructions to make proteins
- Pores allow substances to move between nucleus and cytoplasm
- Nucleolus makes ribosomes
What are mitochondrion?
Oval-shaped organelle with double membrane (inner- cristae, inside- matrix which contains enzymes involved in respiration)
What is the function of mitochondrion?
Site of aerobic respiration where ATP is produced
Where are large amounts of mitochondrion found?
Cells that are very active and require lots of energy
What is a chloroplast?
- Small flattened structure
- Found in plant and algae
- Double membrane
- Membranes inside called thylakoid membranes
- Thylakoid membranes stacked up to form grana
What is the function of a chloroplast?
Site where photosynthesis takes place
What is the Golgi apparatus?
Group of fluid-filled, membrane-bound flattened sacs
What is the function of the Golgi apparatus?
Processes and packages new lipids and proteins and makes lysosomes
Where are Golgi vesicles seen?
Often seen at the edges of sacs
What is a Golgi vesicle?
Small fluid-filled sac in cytoplasm, surrounded by a membrane and produced by Golgi apparatus
What is the function of a Golgi vesicle?
Stores lipids and proteins by the Golgi apparatus and transports them out of the cell
What is a lysosome?
Round organelle surrounded by a membrane with no clear internal structure, type of Golgi vesicle
What is the function of a lysosome?
Contains digestive enzymes (lysozymes) that are used to digest invading cells or break down worn out components of the cell
What is a ribosome?
Very small organelle that either floats freely in cytoplasm or is attached to the rough endoplasmic reticulum, made up of proteins and RNA, not surrounded by a membrane
What is the function of a ribosome?
Site where proteins are made
What is the rough endoplasmic reticulum?
System of membranes enclosing fluid-filled space, surface covered with ribosomes
What is the function of the rough endoplasmic reticulum?
Folds and processes proteins made by ribosomes
What is the smooth endoplasmic reticulum?
Similar to RER but with no ribosomes
What is the function of the smooth endoplasmic reticulum?
Synthesises and processes lipids
What is the cell wall?
Rigid structure surrounding cells in plants, algae and fungi
What is the function of the cell wall?
Supports cells and prevents them changing shape
What is the cell vacuole?
Membrane-bound organelle found in cytoplasm of plant cells that contains cell sap, surrounding membrane called the tonoplast
What is the function of the cell vacuole?
Helps maintain pressure inside cell, keeps cell rigid, involved in isolation of unwanted chemicals inside cell
Why do cells become specialised?
To carry out specific functions
How are epithelial cells in the small intestine specialised to absorb food efficiently?
- Walls of small intestine have villi which increase surface area for absorption
- Villi have folds in cell-surface membrane called microvilli which increase surface area even more
- Also have lots of mitochondria to provide energy for transport of digested food molecules into cell
How are tissues formed?
Specialised cells grouped together
What are tissues?
A group of cells working together to form a particular function
How are organs formed?
Different tissues working together
How are organ systems formed?
Different organs working together to perform a particular function
