1.1 Cells Flashcards
Give examples of prokaryotes.
Unicellular organisms such as bacteria.
________ are the basic building blocks of life. A _____________ organism is made up of one cell, while a ____________ organism is made up of many.
CELLS are the basic building blocks of life. A UNICELLULAR organism is made up of one cell, while a MULTICELLULAR organism is made up of many.
Draw and label an animal cell.
- Ribosomes
- Golgi apparatus
- Lysosomes
- Microvilli
- Mitochondria
- Smooth endoplasmic reticulum
- Cytoplasm
- Cell / plasma membrane
- Nucleolus
- Nucleus
- Rough endoplasmic reticulum
Give an examples of eukaryotes.
Plant and animal cells.
Define a prokaryotic cell.
Prokaryotic means ‘before nucleus’. Prokaryotes have no nucleus and no membrane enclosed organelles.
Draw and label a plant cell
- Ribosomes
- Golgi apparatus
- Lysosomes
- Microvilli
- Mitochondria
- Smooth endoplasmic reticulum
- Cytoplasm
- Cell / plasma membrane
- Nucleolus
- Nucleus
- Rough endoplasmic reticulum
- Chloroplasts
- Large central vacuole
- Cell wall
- Starch grain
Compare and contrast plant and animal cells.
Key differences:
- Cell wall - a cellulose cell wall is only present in plant cells.
- Chloroplasts - not in animal cells.
- Large central vacuole - not in animal cells.
- Carbohydrate storage - starch in plants, glycogen in animals.
Describe the function of the nucleus.
Contains the DNA necessary for controlling the cell including the information for synthesising proteins.
Define a eukaryotic cell.
The name means ‘true nucleus’. Eukaryotes have a nucleus containing the genetic information, and membrane enclosed organelles.
Describe the structure of the nucleus.
The nuclear plasm is surrounded by a double membrane called a nuclear membrane, perforated by nuclear pores. The nucleus contains a nucleolus, and chromatin made from DNA.
Describe the function of mitochondria.
Mitochondria produce energy in the form of ATP via aerobic respiration.
Remember to include examples of what this energy is used for.
Describe the structure of mitochondria.
They are made of a matrix bound by a double membrane. The inner membrane is deeply folded into cristae. The matrix contains lipids, proteins and some DNA.
Explain the structure of mitochondria and it is adapted for its function.
The __________ controls entry and exit of substances.
The __________ is deeply folded to form ______. This increases _________ for respiratory __________.
The OUTER MEMBRANE controls entry and exit of substances.
The INNER MEMBRANE is deeply folded to form CRISTAE. This increases SURFACE AREA for respiratory ENZYMES.
Why did scientists think mitochondria might have originally been a prokaryotic organisms?
They have their own DNA.
They have a double membrane.
What is the ER?
The endoplasmic reticulum is a system of membranes found throughout the cell forming a cytoplasmic skeleton. It is a continuation of the nuclear membrane.
How is the ER structured and how is it adapted for its function?
It is a series of flattened sacs called cisternae. It provides a large surface area for chemical reactions, and a pathway for material transport.
How do the sER and rER differ and what are their functions?
The smooth endoplasmic reticulum synthesises lipids and has no ribosomes on its surface.
The rough endoplasmic reticulum synthesises proteins and is encrusted with ribosomes on its outer surface.
Ribosomes are the __________ organelle, only 25nm in diameter. They can be ____________ or attached to the __________.
They are made of two ___________. A _____________ and a ___________. They are made of ________ synthesised in the _________.
Ribosomes perform __________, making _______ from ______________.
Ribosomes are the SMALLEST organelle, only 25nm in diameter. They can be FREE FLOATING or attached to the ROUGH ENDOPLASMIC RETICULUM.
They are made of two SUB-UNITS. A LARGE SUB-UNIT and a SMALL SUB-UNIT. They are made of RIBOSOMAL RNA synthesised in the NUCLEOLUS. Ribosomes perform PROTEIN SYNTHESIS making PROTEINS from AMINO ACIDS.
Describe the function of the Golgi apparatus.
The Golgi apparatus sorts, processes, modifies and packages proteins and lipids produced by the cell into vesicles. Vesicles may also be used to produce lysosomes in the Golgi.
Describe the structure of the Golgi apparatus.
The Golgi apparatus is composed of flattened sacs made if membranes. The saves are fluid filled and pinch off smaller sacs at their ends - vesicles.
There is usually only ____ Golgi apparatus in each cell. It is well developed in ___________ cells as _____________ must be packaged into _________ to be transported out of the cell.
There is usually only ONE Golgi apparatus in each cell. It is well developed in SECRETORY cells as LARGE MOLECULES must be packaged into VESICLES to be transported out of the cell.
What is the function of vesicles, and how are they suited to this function?
Vesicles allow large, insoluble molecules such as proteins to leave the cell via exocytosis. Vesicles are made of phospholipid bilayer like the cell membrane so they can fuse and excrete the substance outside the cell.
Vesicles may also distribute substances around the cell, or form lysosomes.
What is the function of lysosomes? And which cells may contain many?
Lysosomes are used to break down unwanted structures in the cell such as pathogens or damaged organelles. Phagocytes contain many lysosomes to break down pathogens.
Lysosomes are similar in size to __________. They are bound by a __________ membrane. The have no ________________. They contain a large number of ________ called __________. They are mainly ___________ in an _____ solution. This must be kept separate from the rest if the cell to avoid ____________.
Lysosomes are similar in size to MITOCHONDRIA. They are bound by a SINGLE membrane. The have no INTERNAL STRUCTURE They contain a large number of ENZYMES called LYSOZYMES. They are mainly HYDROLASES in an ACID solution. This must be kept separate from the rest if the cell to avoid DAMAGE.