Topic 1: Key concepts in biology Flashcards
State the two types of cells
Prokaryotic and Eukaryotic
What is the difference between a Eukaryotic and Prokaryotic cell?
Eukaryotic cell has a nucleus and membrane-bound organelles, unlike a Prokaryotic cell
List the components of both animal and plant cells
Mitochondria
Nucleus
Cytoplasm
Ribosomes
Cell membrane
How is genetic information stored in a Eukaryotic cell?
In the nucleus, arranged in chromosomes
What is the function of the nucleus?
Contains genetic information and controls cellular activity
Describe the structure of the cytoplasm
Fluid gel-like substance containing enzymes
What is the function of the cytoplasm?
Site where chemical reactions take place (respiration)
What is the function of the cell membrane?
Holds cell together and controls movement of substances in and out of the cell
What is the function of the Mitochondria?
Site where energy is released for respiration
What is the function of the ribosomes?
Join amino acids in a specific order during translation
What is the cell wall made of?
Cellulose
Which 3 organelles are only found in plant cells?
Cell wall
Vacuole
Chloroplasts
What is the function of the cell wall?
Provides strength and structural support
What does the vacuole contain?
Cell sap, a weak solution of sugars and salts
What is the function of the vacuole?
Maintains internal pressure to support cell
What is the function of the chloroplasts?
Site of photosynthesis
Why do chloroplasts appear green under a light microscope?
Contain the green pigment chlorophyll
List the six organelles found in prokaryotic cells
Plasmid DNA
Chromosomal DNA
Ribosomes
Cell wall
Cell membrane
Flagella
How is genetic information stored in a Prokaryotic cell?
Found free within the cytoplasm as chromosomal or plasmid DNA
What are plasmids?
Small circular loops of DNA which are separate from the main DNA. They carry genes that provide genetic advantages such as antibiotic resistance
What is the Prokaryotic cell wall composed of?
Peptidoglycan
What is a flagellum?
Long, rotating, ‘whip like’ protrusion that enables bacteria to move
What is a haploid cell?
A cell with a single copy of each chromosome (23 chromosomes)
What is a diploid cell?
A cell with two copies of each chromosome (46 chromosomes)
What are gametes?
The reproductive cells: egg and sperm cell which are haploid cells