Cells Flashcards
What are all organisms made of?
One or more cells
What is a cell?
The basic unit of organisms
Where do all cells come from?
Pre-existing cells
What are single-celled organisms?
All bacteria
Most of the proctoctista
Some fungi (eg. Yeast)
What are the 7 life processes?
Movement Respiration Sensitivity Nutrition Excretion Reproduction Growth
What is a cell organelle?
A structure within a cell
What does the cell membrane do?
Controls the passage of substances in and out of the cell
Contains receptor molecules to receive signals
What is the cytoplasm?
The site of most chemical reactions that take place within a cell
What does the nucleus contain and what does it do?
Contains the genetic material and controls the activities of the cell
What is the mitochondria
The site of aerobic respiration and the enzymes for this
What are the ribosomes?
The site of protein synthesis
What is the cell wall made from?
Cellulose
What does the cell wall do?
Provide structural support
What does the vacuole contain? (Plant cell)
Cell sap
What does the vacuole do?
Provides support
What do the chloroplasts contain?
Chlorophyll
What are chloroplasts?
The site of photosynthesis
Name 3 cell organelles found in a plant cell but not an animal cell
Chloroplasts
Permanent vacuole
Cell wall
What is a prokaryote?
A cell with no nucleus (nuclear material lies free in the cytoplasm), a single-called organism, may contain additional DNA in the form of a plasmid
What is a eukaryote?
A cell with a nucleus bound by a nuclear membrane
What does it mean when a plant cell is turgid?
When water moves into a plant cell by osmosis and causes the cytoplasm to push against the cell wall
What does it mean when a plant cell is flaccid?
When water diffuses out of a plant cell by osmosis, causing the cytoplasm to move away from the cell wall
What is plasmolysis?
A plant cell placed in a concentrated solution, causing water to move out of the cell and draw the cytoplasm away from the cell wall
What is crenation?
When a cell is placed in a concentrated solution and water diffuses out
What is lysis?
When a cell is placed in a dilute solution, causing water to move into the cell and causing the cell to burst
Can a plant cell experience lysis?
No, the cell wall prevents the cell from bursting, it becomes turgid instead
What is haemolysis
When a red blood cell bursts due to being placed in a dilute solution
How can you describe the cells in a wilted plant?
Flaccid
Why don’t plant cells burst when placed in a dilute solution?
The cellulose cell wall can resist the turgor pressure of the cytoplasm
