classification Flashcards
define movement
an action by an organism (or part of an organism) resulting in a change of position
define respiration
chemical reactions in cells that breakdown nutrient molecules and release energy
define sensitivity
ability to decent and respond to stimuli in the internal or external environment
define growth
a permanent increase in dry mass
define reproduction
process that makes more of the same kind of organism
define excretion
removal of toxic material, metabolic waste and excess substances from an organism
define nutrition
the taking in of materials for energy, growth, and development
define species
a group of organisms that can reproduce and produce fertile offspring
define binomial system
an internationally agreed system where the scientific name of an organism is made up of two parts consisting of the genus and species
define DNA
long twisted double stranded (double helix) molecule held together by pairs of chemical units called bases
adenine pairs with
thymine
cytosine pairs with
guanine
classification systems aim to
reflect evolutionary relationships
similar base sequences mean
they are more closely related since few mutations occurred
4 key features of animals
- take in and use organic materials from other organisms for energy
- able to move from one place to the other
- most reproduce sexually using reproductive cells (gametes)
- no cell wall surrounding cell membrane
3 key features of plants
- make their own food by photosynthesis
- cells are surrounded by cellulose cell wall
- few identifiable organs (flowers, leaves, stem)
4 key features of prokaryotes
- unicellular
- no membrane-bound organelles so no true nucleus (DNA is loose in cytoplasm)
- killed by antibiotics
- have cell wall
define protoctista
group of largely microscopic truly living organisms
4 key features of protoctists
- mostly unicellular some multicellular
- have membrane-bound organelles (have a true nucleus)
- respire aerobically
- either free-living or parasitic
4 key features of fungi
- chitin cell wall
- have no chlorophyll
- reproduce by producing spores
- made of large number of tubular threads (hyphae) intertwined to form mycelium
2 features of virus
- protein coat
- contain genetic material
3 key features of fish
- gills for breathing
- covered in scales + fins for movement
- lay jelly-covered eggs in water
3 key features of amphibians
- webbed feet
- moist skin
- can live in land and water but always lay eggs in water
2 key features of reptiles
- scaly skin
- leathery-shelled eggs on land
4 key features of birds
- forelimbs are wings
- warm-blooded
- four-chambered heart
- beak for feeding
4 key features of mammals
- produce live young (feed from mammary glands)
- hair on body
- internal fertilisation
- ears with external flaps
define vertebrates
animals that have a vertebral column
define invertebrates
animals that don’t have a vertebral column
2 features of arthropods
- jointed legs
- segmented body
4 key features of insects
- three pairs of legs
- head, thorax, abdomen
- one pair of antennae
- one or two pairs of wings
4 key features of crustaceans
- four pairs of legs
- cephalothorax, abdomen
- two pairs of antennae
- exoskeleton made of calcium salts
3 key features of arachnids
- four pairs of legs
- cephalothorax, abdomen
- no antennae
2 key features of myriapods
- ten or more pairs of legs (one or two each segment)
- one pair of antennae
two major divisions of plant kingdom
ferns and flowering plants
4 key features of ferns
- don’t produce flowers
- reproduce by producing spores
- leaves are called fronds
- green and photosynthesise
5 key features of monocotyledons
- one cotyledon in each seed
- narrow leaves
- parallel veins
- petals in threes
- fibrous roots
5 key features of dicotyledons
- two cotyledons in each seed
- broad leaves
- network-like branching veins
- petals in fours/fives
- taproot system
