Variety of organisms - Unit 1 Flashcards
there are 8 characteristics of a living organism. What are they?
the 8 characteristics are..
- move
- respire
- sensitivity
- control internal conditions
- grow
- reproduce
- excrete
- need nutrition
characteristic 1: Move
- animals move from place to place
- organisms can move towards food/ water
- organisms can move away from predators
- plants can move slightly but not from the spot
characteristic 2: Respire
- respiration is the release of energy from food (glucose)
- Aerobic respiration: Glucose + oxygen -> carbon dioxide + water
- Anaerobic respiration in animals: glucose -> lactic acid
- Anaerobic respiration in plants and yeast: glucose -> ethanol + carbon dioxide
characteristic 3: Sensitivity
They can respond to changes in their movement (a stimulus)
Examples include reflex actions such as moving your hand away from a hot objet (reflex arc).
And the iris reflex (dilating in dim light, constructing in bright light).
characteristic 4: Control inter conditions
Homeostasis - maintenance of a constant internal environment.
Thermoregulation - maintenance of constant internal temperature.
Osmoregulation - maintenance of water levels.
characteristic 5: Grow
Increase in size/ mass of an organism, increase in number of cells.
characteristic 6: Reproduce
Produce offspring
sexual reproduction: involves fertilisation of gametes (sex cells), offspring are genetically different, results in variation within species.
Asexual reproduction: 1 parent, involves cell division by mitosis, genetically identical offspring.
characteristic 7: Excrete
Removal of waste metabolic products
- carbon dioxide from respiration (removed by lungs in animals, stomata in plants)
- urea from excess amino acids (removed by the kidneys, in urine)
characteristic 8: Need nutrition
Requiring such as…
glucose to provide them with energy (through respiration).
Proteins for amino acids.
Vitamins and minerals.
(specifically mineral ions in plants - very important)
Why are viruses not considered living organisms?
Because they do not…
- respire
- move
- excrete waste products
- require nutrition
- grow and develop
- control internal conditions
- respond to their surroundings
- reproduce without a host
what are eukaryotic cells
Complex cells
Includes all animal and plant cells
Plants, animals, fungi and protoctists are all eukaryotic organisms -> they have a nucleus and a membrane bound organelles.
what are prokaryotic cells
Smaller and simpler
e.g -> bacteria
Bacteria are prokaryotes -> no nucleus - just circular chromosome (nucleoid) and plasmids.
What are the 5 kingdoms?
- plants
- fungi
- animals
- protoctists
- bacteria
about plants…
Multicellular (made of many cells)
have chloroplast which contains chlorophyll
photosynthesis to produce glucose
cell walls made from cellulose
store carbohydrates as starch (& sucrose)
about animals…
multicellular (made of many cells) no chloroplast - do not photosynthesise no cell wall have nervous coordinations move from place to place store carbohydrates as glycogen