Organisms Flashcards
Characteristics of living organisms
Movement
Respiration
Sensitivity
Control
Growth
Reproduction
Excretion
Nutrition
What are the 2 types of cells
Eukaryotic
Prokaryotic
What does an animal cell contain
Nucleus
Cytoplasm
Ribosomes
Cell membrane
Mitochondria
What does a plant cell contain
Nucleus
Cytoplasm
Ribosomes
Cell membrane
Cell wall
Mitochondria
Chloroplasts
Vacuole
Nucleus function
Controls the activities of the cell using genes
Cytoplasm function
Where the cell’s chemical reactions occur
Cell membrane function
Controls what enters and exits the cell
Mitochondria function
Site of respiration - releases energy
Cell wall function
Helps maintain the shape of the cell
Vacuole function
Filled with cell sap which helps keeps the cell’s shape
Chloroplasts function
Absorbs light energy for photosynthesis
Ribosomes function
Site of protein synthesis
Levels of organisation
Organelle —> cells —> tissues —> organs —> organ systems —> organism
Cell differentiation definition
The process by which cells become specialised to perform specific functions
Plants - features (5) and example
-Eukaryotic
-Multicellular
-Contains chloroplasts - can photosynthesise
-Cell walls made of cellulose
-Store carbs as starch or sucrose
e.g. maize, moss
Animals - features (5) and example
-eukaryotic
-multicellular
-no chloroplasts - no photosynthesis
-no cell walls
-store carbohydrates as glycogen
e.g. mammals and insects
Fungi - features (6) and example
-eukaryotic
-cell walls made of chitin
-no chloroplasts - no photosynthesis
-some single celled, some made of hyphae
-saprotrophic nutrition
-store carbs as glycogen
e.g. yeast
Protoctista - features (5) and example
-‘dustbin cell’ - not specific
-eukaryotic
-single cellular/multi cellular
-no carb store
-microscopic
e.g. amoeba
Bacteria - features (6) and examples
-prokaryotic
-single celled
-microscopic
-no nucleus
-circular chromosome of DNA
-some photosynthesise
-most feed off other organisms
e.g. lactobacillus
Viruses - features (5) and examples
-particles, not cells
-only reproduce inside living cells
-infect all types of living organisms
-come in variety of shapes + sizes
-protein coat around genetic material
e.g. tobacco mosaic virus, HIV
Catalyst definition
A substance which increases the speed of a reaction without being used up itself
Enzyme lock and key model process
- Substrate collides with active site of enzyme and becomes attached
- Enzyme catalyses breakdown of substrate
- Products released from active site
- Enzyme molecule is unchanged and can be reused
How do enzymes work
Catalyse reactions by providing an alternative route with a lower activation energy
Factors affecting rate of enzymes
Temperature
PH
Enzyme concentration
Substrate concentration
