The Fundamental Unit of Life Flashcards
Person who discovered the cell
Robert Hooke
‘Cell’ meaning in latin
A little room
The year the Cell was discovered
1665
How the cell was discovered
Robert Hooke was examining a thin slice of cork using his self-designed microscope, in which he saw that the cork resembled the shape of a honeycomb consisting of many compartments.
Fundamental unit of Life
The Cell
Unicellular Organisms
The organisms made up of a single cell
Multicellular Organisms
The organisms are made up of more than one cell that groups together perform different functions
Things all cells contain
- Plasma Membrane
- Cytoplasm
- Nucleus
Plasma Membrane
A semipermeable membrane that separates the interior of a cell from the outside environment.
Plasma membrane is made up of ___.
Proteins and Lipids
Why is Plasma Membrane said to be semi permeable?
The plasma membrane allows certain substances to enter and leave the cell.
What is diffusion?
Diffusion is the movement of molecules through a semipermeable barrier from an area of higher concentration to a an area with lower concentration.
What is Osmosis?
Osmosis is the process by which solvent molecules pass from a solution of low concentration to a solution of high concentration through a semi-permeable membrane.
What are the different types of osmotic solutions?
- Hypotonic
- Isotonic
- Hypertonic
What is a hypotonic solution?
A hypotonic solution is one that has a higher solute concentration inside the cell than outside.
What is an isotonic solution?
An isotonic solution is a solution that has the same concentration of solutes both inside and outside the cell.
What is a hypertonic solution?
A hypertonic solution is a solution that has a higher solute concentration outside the cell than inside.
What are the types of osmosis?
- Endo-osmosis
2. Exo-osmosis
What is endo-osmosis?
When a substance is placed in a hypotonic solution, the solvent molecules move inside the cell and the cell becomes turgid or undergoes deplasmolysis. This is known as endosmosis.
What is exo-osmosis?
When a cell is placed in a hypertonic solution, the solvent molecules move outside the cell and the cell becomes flaccid. This is called exo-osmosis.
What is plasmolysis?
Plasmolysis is the process in which living plant cells lose water in a hypertonic solution.
What is endocytosis?
Endocytosis is the process by which cells take in substances from outside the cell by engulfing them in a vesicle.
What is phagosytosis?
Phagocytosis is the process in which cells internalize large particles or cells to collect nutrients from them. This process is also known as eating.
What is pinocytosis?
Pinocytosis is the process in which cells take in substances from the extracellular fluid that it needs to function. Some fluids are water and nutrients.
What is exocytosis?
Exocytosis is the process by which cells move materials from within the cell into the extracellular fluid.
What is a cell wall?
The cell wall is an added layer of protection given to plant cells.
What is the nucleus?
The nucleus is a double-membraned organelle that contains the genetic material and other materials required to
What is the nucleus?
The nucleus is a double-membraned organelle that contains the genetic material and other materials required for cellular processes.
What are the fibres that the cell contains?
Chromatin Fibres
What do chromatin fibres contain?
The genetic material
What do chromatin structures make?
Chromosomes
What are chromosomes made of?
Genes
What do genes determine?
Hereditary qualities
What are genes made up of?
DNA (Deoxyribonucleic Acids)
What kind of structure does DNA have?
A double helix
Do all cells have a well-defined nucleus?
No
What cells don’t have a well-defined nucleus?
Prokaryotic cells
Which cells have a well-defined nucleus?
Eukaryotic cells
Why does the nucleus have pores?
The nuclear membrane has pores to transfer material from inside the nucleus to its outside.
What is the cytoplasm?
The cytoplasm is the fluid content inside the plasma membrane.
What does the cytoplasm contain?
The cytoplasm contains organelles
What are cell organelles?
Cell organelles are subcellular structures in a cell that has a specific function in the cell.
What is the endoplasmic reticulum?
The endoplasmic reticulum is a large network of membrane-bound tubes and sheets.
What does ER look like?
It looks like long tubules or round or oblong bags (vesicles).
What are the two types of ER?
- Smooth Endoplasmic Reticulum (SER)
2. Rough Endoplasmic Reticulum (RER)
Why does RER look rough?
Because there are particles called ribosomes attached to the surface.
What are ribosomes?`
They are the sites of protein manufacture.
