1. Characteristics and classification of living organisms Flashcards
What is movement?
the action of an organism or a part of it which causes a change in position/place
What is respiration?
chemical reaction that takes place in cells which break down nutrient molecules, releasing energy (for metabolism)
What is sensitivity?
the ability to detect and respond to changes in the internal/external environment
What is growth?
the permanent increase in size and dry mass
What is reproduction?
the process which makes more of the same type of organism
What is excretion?
removal of toxic waste products of metabolism and of substances which are in excess
What is nutrition?
the taking in of nutrients/materials for growth, energy and development
What are some examples of excretory products?
CO2, urea and sweat
What are some processes of excretion?
exhaling + gas exchange
urination
thermoregulation
What is egestion?
removal of undigested material as faeces
What is an example of sensitivity?
leaves changing direction to face sun
What are the main features used to group animals/plants into their kingdoms?
movement
respiration
sensitivity
growth
reproduction
excretion
nutrition
What are leaves from monocotyledons like?
they have parallel leaf veins
What are leaves from dicotyledons like?
have reticulated leaf veins (web-like)
What are flowers from dicotyledons like?
petals in multiples of 4/5
What are flowers from monocotyledons like?
petals in multiples of 3
What are features of the animal kingdom?
move
sexual reproduction
cells have nucleus
multicellular
respire through mitochondria and cytoplasm
both passive and active mechanism
heterotrophic nutrition
Which kingdoms are or can be heterotrophic?
animal, prokaryote, protist and fungi (all except plant)
Which is the only only autotrophic kingdom?
plant
Which kingdom contains only unicellular organisms?
prokaryote
What two kingdoms can use active mechanism of excretion?
animal and plant
What are the features (simple structure) of viruses?
protein coat and genetic material
Which kingdom only contains organisms with no nucleus?
prokaryote
How can organisms be classified into groups?
by the features that they share
What is a species?
a group of organisms that
can reproduce to produce fertile offspring
What is the binomial system of naming species?
an internationally agreed system in which the
scientific name of an organism is made up of two
parts, showing the genus and species
What do classification systems aim to do?
reflect
evolutionary relationships
What is used as a means of classification?
the sequences of bases in DNA
What do groups of organisms which share a more recent ancestor have in common?
have base sequences in DNA that are more
similar than those that share only a distant ancestor
What are the main vertebrate groups?
mammals,
birds, reptiles, amphibians, fish
What are the main arthropod groups?
myriapods, insects, arachnids, crustaceans
Features of mammals
- warm blooded
- breathe w/ lungs
- land or/and water
- fur/hair
- external ear
- almost all give birth to live young ones
- feed young w/ milk
Features of birds
- warm blooded
- breathe w/ lungs
- feathers
- streamlined, reduce air resistance
- forelimbs = wings and hindlimbs = scaly and claws
- feed w/ beaks
- internal fertilisation
Features of reptiles
- cold blooded
- body covered in scales or plates preventing water loss
- breathe w/ lungs
- most have 4 limbs/legs, each with 5 toes + claws
- internal fertilisation
Features of amphibians
- cold blooded
- slimy, moist skin, no scales
- eggs laid in water, external fertilisation
- adults mostly live on land but return to water for fertilisation
- eggs hatch into tadpoles living in water
- adults: lungs / tadpoles: gills
- moist skin also helps to breathe
Features of fish
- cold blooded
- aquatic
- almost all breathe w/ gills
- scales cover body
- fins: help swim
- streamlined shape: minimises resistance
- eggs laid in water, external fertilisation
Features of myriapods
- many legs (1/2 pairs per body segment)
- many body parts, no distinct thorax/abdomen
- one pair of antenna
- no wings
Features of insects
- six legs
- head, thorax, abdomen
- one pair of antenna
- 1/2 pairs of wings
Features of arachnids
- eight legs
- cephalothorax and abdomen
- no antenna nor wings
Features of crustaceans
- 10+ legs
- head, thorax, abdomen (sometimes cephalothorax)
- two pairs of antenna
- no wings
What is the cephalothorax?
head and thorax fused
What do viruses consist of?
protein coat, genetic material
Animal features
multicellular heterotrophs
Protoctist features
most are unicellular, can be auto/heterotrophs
Prokaryote features
unicellular. can be auto/heterotrophs. autotrophs have chlorophyll but no chloroplasts
Plant features
multicellular autotrophs
Fungus features
may be uni or multicellular. some are heterotrophs and some are sapotrophs
Dicotyledon features
two cotyledons
network of veins
leaves are broad and short
vascular bundles arranged in a ring in the stem
tap root
petals in 4/5 multiples
Monocotyledon features
one cotyledon
parallel veins
leaves are narrow and long
vascular bundles scattered in stem
fibrous roots
petals in multiples of 3
Fern features
roots, stem and fronds
leaves produce spores, which are light and dispersed by wind to germinate and grow into new fern plants
stem below ground
Flowering plants features
seeds formed in flowers
monocotyledon or dicotyledon
