Key Concepts in Biology Flashcards
What are the two type of cells?
- Eukaryotic
- Prokaryotic
What is the difference between a eukaryotic and prokaryotic cell?
A eukaryotic cell contains a nucleus and membrane-bound organelles, a prokayotic cell doesn’t.
What are the five components both animal and plants cells have?
- Nucleus
- Cytoplasm
- Cell membrane
- Mitochondria
- Ribosomes
How is genetic information stored in a eukaryotic cell?
Within the nucleus, arranged in chromosomes.
Other than storing genetic information, what is the function of the nucleus?
Controls cellular activities.
What’s the structure of the cytoplasm?
- Fluid component of the cell
- Contains organelles, enzymes and dissolved ions and nutrients
What is the function of the cytoplasm?
Site of cellular reaction, e.g. first stage of respiration
What is the function of the cell membrane?
Controls the entry and exit of materials into and out of the cell
What is the function of the mitochondria?
Site of later stages of aerobic respiration in which ATP is produced
What is the function of the ribosomes?
Joins amino acids in a specific order during translation
Which organelles are found in plant cells only?
- Large, permanent vacuole
- Cell wall
- Chloroplasts
What is the cell wall made of?
Cellulose
What is the function of the cell wall?
- Provides strength
- Prevents the cell bursting when water enters by osmosis
What does the permanent vacuole contain?
A solution of salts, sugars, and organic acids
What is the function of the permant vacuole?
Supports the cell, maintaininf its turgidity
What is the function of the chloroplasts?
Site of photosynthesis
When looking at a cell using a light microscope, why do chloroplasts appear green?
Contain chlorophyll, a green pigment
Which six organelles are found in prokaryotic cells?
- Chromosomal DNA
- Plasmid DNA
- Cell Wall
- Cell Membrane
- Ribosomes
- Flagella
How is genetic information stored in a prokaryotic cell?
Found free within the cytoplasm as:
* Chromosomal DNA (single large loop of circular DNA)
* Plasmid DNA
What are plasmids?
- Small, circular loops of DNA found free in the cytoplasm and separate from the main DNA
- Carry genes that provide genetic advantages, e.g. antibiotic resistance
What is the prokaryotic cell wall composed of?
Peptidogylycan
What is a flagellum?
- Long, rotating, ‘whip-like’ protrusion
- Enables bacteria to move