B1 | Characteristics & Classification of Living Organisms

• The characteristics of living organisms are:

  • Movement
  • Respiration
  • Sensitivity
  • Growth
  • Reproduction
  • Excretion
  • Nutrition
• Movement


  Something an organism or part of an organism does that causes it to change its position or place
• Respiration

  The chemical reactions that break down nutrients in living cells to release energy for metabolism
• Sensitivity

  The ability to detect or sense stimuli in the internal or external environment and to make appropriate responses
• Growth

  A permanent increase in size and dry mass by an increase in number of cells, size of cells, or both
• Reproduction

  The processes that make more of the same kind of organism
• Excretion

  The removal of toxic materials, waste products of metabolism, and substances that have an excess of requirements from the organism's body.
• Nutrition

  The taking in of materials for energy, growth, and development.

  Plants require light, carbon dioxide, water, and ions.

  Animals need organic compounds, ions and, usually water
• Species

  A group of organisms that can reproduce to produce fertile offspring

  • These species are classified into groups by the features they share
• You can remember Linnaeus's system of classification by:

  King Philip Came Over For Great Spaghetti
• • Classification systems aim to reflect evolutionary relationships between species
  • Traditional biological classification systems grouped organisms based on the features that they shared
  • If organisms shared more similar features then they were said to be more closely related
  • In the past, scientists have encountered many difficulties when trying to determine the evolutionary relationships of species based on this method
  • Using the physical features of species (such as color/shape/size) has many limitations and can often lead to the wrong classification of species
• • Organisms from a common ancestor share features
  • Originally, animals were classified using morphology (form and shape) and anatomy (detailed body structure)
  • As technology advanced, microscopes, knowledge of biochemistry, and DNA sequencing allowed us to classify organisms more scientifically
  • DNA sequences show that the more similar sequences two species have, the more closely related they are
  • This means that the base sequences in mammal's DNA are more closely related to other mammals than to any other vertebrate groups

  Which animals in these DNA sequences look the most similar?

  
• Linnaeus’s system of classification

  A) kingdom

  B) phylum

  C) class

  D) order

  E) family

  F) genus

  G) species

  
• • The first division of living things is to put them in one of five kingdoms:
  • Animals
  • Plants
  • Fungi
  • Protoctists
  • Prokaryotes
• • Main features of all animals
  • They are multicellular
  • Their cells contain a nucleus but no cell walls or chloroplasts
  • They feed on organic substances made by other things

  A) mitochondria

  B) nucleus

  C) cell membrane

  D) ribosomes

  E) cytoplasm

  
• • Main features of all plants
  • They are multicellular
  • Their cells contain a nucleus, chloroplasts, and cell walls
  • They are all fed by photosynthesis

  A) cell membrane

  B) chloroplast

  C) cell wall

  D) ribosomes

  E) nucleus

  F) mitochondria

  G) vacuole

  H) cytoplasm

  
• • All vertebrates have a backbone
  • There are 5 classes of vertebrates

  A) fur/hair

  B) placenta

  C) milk

  D) ears

  E) endothermic

  F) feathers

  G) legs

  H) wings

  I) eggs

  J) beak

  K) endothermic

  L) scales

  M) eggs

  N) rubbery

  O) hard

  P) moist

  Q) land

  R) larvae

  S) eggs without shells

  T) wet scales

  U) gills

  V) eggs without shells

  
• Invertebrates

  • Don't have a backbone
  • Have jointed legs

  A) segments

  B) jointed

  C) antennae

  D) abdomen

  E) thorax

  F) jointed legs

  G) wings

  H) antennae

  I) 4 pairs

  J) jointed

  K) no antennae

  L) 4 pairs

  M) jointed

  N) chalky

  O) calcium

  P) gills

  Q) antennae

  
• • Main features of all fungi
  • Usually multicellular
  • Cells have nuclei and cell walls not made from cellulose
  • Do not photosynthesize, but feed by saprophytic (on dead animals) or parasitic (on live animals) nutrition

  A) nucleus

  B) cell wall

  C) cell membrane

  D) ribosomes

  E) mitochondria

  F) cytoplasm

  
• • Main features of all Protoctists
  • Most are unicellular
  • All have a nucleus, some may have cell walls and chloroplasts
  • Meaning some protoctists photosynthesise and some feed on organic substances made by other living things

  A) food

  B) ribosomes

  C) cell membrane

  D) mitochondria

  E) cytoplasm

  F) contractile vacuole

  G) ribosomes

  
• • Main features of all Prokaryotes
  • Often unicellular
  • Cells have cell walls and cytoplasm, but no nucleus or mitrochondria

  A) cell membrane

  B) cell wall

  C) cytoplasm

  D) dna

  E) plasmid

  F) ribosomes

  
• • Viruses are not part of any classification system because they're not considered living things
  • They don't carry out the seven life processes for themselves. They take over a host cell's metabolic pathways to dublicate
  • Virus structure is simply genetic material (DNA/RNA) inside a protein coat

  A) envelope

  B) protein

  C) dna

  
• • The first division of living things in the classification system is to put them into one of five kingdoms. They are:
  • Animals
  • Plants
  • Fungi
  • Protoctists
  • Prokaryotes
• • Main features of all plants:
  • they are multicellular
  • their cells contain a nucleus, chloroplasts and cellulose cell walls
  • they all feed by photosynthesis

  
• • Main features of all animals:
  • they are multicellular
  • their cells contain a nucleus but no cell walls or chloroplasts
  • they feed on organic substances made by other living things

  
• Vertebrates

  • All vertebrates have a backbone
  • There are 5 classes of vertebrates

  A) placenta

  B) mammary glands

  C) pinna

  D) endo

  E) feathers

  F) 2

  G) 2

  H) hard

  I) beak

  J) endo

  K) scales

  L) rubbery

  M) moist

  N) land

  O) larvae

  P) without

  Q) wet scales

  R) gills

  S) without

  
• • Main features of all fungi (e.g. moulds, mushrooms, yeast)
  • usually multicellular
  • cells have nuclei and cell walls not made from cellulose
  • do not photosynthesize but feed by saprophytic (on dead or decaying material) or parasitic (on live material) nutrition

  A) chitin

  
• • Main features of all Protoctists (e.g. Amoeba, Paramecium, Plasmodium)
  • most are unicellular but some are multicellular
  • all have a nucleus, some may have cell walls and chloroplasts
  • meaning some protoctists photosynthesise and some feed on organic substances made by other living things

  A) water

  
• • Main features of all Prokaryotes (bacteria, blue-green algae)
  • often unicellular
  • cells have cell walls (not made of cellulose) and cytoplasm but no nucleus or mitochondria

  A) DNA

  B) plasmid