Chapter 1- Cell biology Flashcards
What is a cell?
The smallest unit of life that can live on its own. Cells make up all living organisms and their tissues.
What are the differences between eukaryotic and prokaryotic cells?
- Eukaryotic cells are much larger.
- Eukaryotic cells contain membrane-bound organelles, while prokaryotic cells do not.
- Eukaryotic cells keep their DNA in the form of chromosomes within a nucleus, whilst prokaryotic cells have their DNA loose in the cell.
Are animal and plant cells prokaryotic or eukaryotic cells?
Eukaryotic cells.
Is a bacterial cell prokaryotic or eukaryotic?
Prokaryotic.
Name five sub-cellular structures found in both animal and plant cells.
Cell membrane, ribosomes, Nucleus, Mitochondria, cytoplasm.
What is the cell membrane and its role?
It is a protective barrier around the outside of the cell. It controls which substances can pass in and out of the cell.
What is the cytoplasm and what is its role?
A jelly like liquid that fills the cell. It allows substances to dissolve and chemical reactions take place.
What is the role of the nucleus?
It contains the genetic material of the cell and so controls what the cell does.
What is the role of the mitochondria?
They carry out aerobic respiration, so provide energy for the cell to use in chemical reactions.
What is the role of the ribosomes?
They are the sight of protein synthesis ( where proteins are made)
Name 3 sub-cellular structures (organelles) that are found in plant cells but not in animal cells.
Cell wall, chloroplast and permanent vacuole.
In plants, what is the cell wall made of?
Cellulose
What is the role of the plant cell wall?
It provides strength and structure to the plant cell, preventing it from bursting or shrinking when water enters/leaves the cell via osmosis.
What does the permanent vacuole contain?
Cell sap (full of sugars salts and amino acids).
What is the role of chloroplasts?
Chloroplasts are the site of photosynthesis and so they make glucose for the cell.
What is chlorophyll?
A green substance that absorbs light for photosynthesis.
Name 7 sub-cellular structures (organelles) that are found in bacterial cells.
Cytoplasm, Cell membrane, Cell wall, plasmids, singular strands of DNA, may have flagella.
What is the role of the permanent vacuole?
A chemical store that helps with the support of the cell, giving it extra nutrients.
What are plasmids, and what are their role?
It contains additional genes, such as for antibiotic resistance.
What is the definition of magnification?
How many times larger an image seen through a microscope is compared to the real object
What is the role of a microscope?
To produce magnified images that you are unable to see with the human eye.
Define resolution
A measure of the microscope’s ability to distinguish between two points which are close together on an object.