Topic 5.3 - Classification and biodiversity Flashcards
Binomial systems
Universal among biologists and has been agreed and developed at a series of congresses.
Genus begins with a capital letter, species begins with a lower case, the whole name is in italics.
Hierarchy of taxa
Domain - Kingdom - Phylum - Class - Order - Family - Genus - Species
Domain
Domain ->
Eukarya, Prokarya, archae
Kingdom
Kingdom ->
(Eukarya) - Animalia, Protista, Fungi, Plantae
(Archaebacteria, Eubacteria - if splitting up further // not required for ib)
Phylum
Phylum ->
(Animalia) - Porifera, Coelenterata, Platyhelminthes, Nematoda, Annelida, Arthropoda, Mollusca, Echinodermata, Protochordata, Vertebrata
(Plantae) - Bryophyta (mosses, liverworts, hornworts), Coniferophyta (conifers), Angiospermatophyta (flowering plants), Filicinophyta (ferns).
Class
Class ->
(Vertebrata) - Pisces, Amphibia, Reptilia, Aves, Mammalia
(Chordata) - Agnatha (jaw-less fish), Chondrichthyes (cartilaginous fish), Osteichthyes (bony fish), Amphibia, Reptilia, Aves, Mammalia
Order
Order ->
(Mammalia) - Chiropptera (bats), Primates, Rodentia (gnawing animals), Cetacea (whales, dolphins), Carnivora, Artiodactyla (even toed mammals)
Family
Family ->
(Primates) -
Monkeys -> (Platyrrhines - new world (in Americas) and Catarrhines/Cercopithecoids (old world))
Hominidae -> (Apes, Humans, bonobo, orangutan)
Prosimians -> (Tarrsiiformes and Lemuriformes)
Carnivora - Felidae (Cats), Canidae (Dogs), Ursidae (Bears), and Mustelidae (Weasels)
Genus
Genus ->
Hominidae) - Homo, Pongo (orangu), Gorilla, Pan (chimp, bonobo
Species
Species ->
(Homo) - sapien, neanderthalensis
Organisms that can interbreed to form fertile offspring
Dactyl
Finger/toe
Artio
Even
Bacteria
Histones associated with DNA -
Absent
Introns -
Rare/Absent
Ribosome size -
70s
Cell wall properties -
Peptidoglycan
Cell membrane -
Glycerol-ester lipids, unbranched side chains, d-glycerol
Archaea
Histones associated with DNA -
Proteins similar to histones
Introns -
Present in some genes
Ribosome size -
70s
Cell wall properties -
Not made of peptidoglycan; if present, mostly composed of glycan polymers.
Cell membrane -
Glycerol-ether lipids, unbranched side chains, l-lipids
Eukaryota
Histones associated with DNA -
Present
Introns -
Frequently present
Ribosome size -
80s
Cell wall properties -
Animals -> no, plants -> cellulose, fungi -> chitin
Cell membrane -
Glycerol-ester lipids, unbranched side chains, d-glycerol
Archaean
Found everywhere, even in extreme conditions.
Methanogens
Type of Archaean, produce methane (found in stomachs of cattle/termites).
Natural classification
Species in a genus and higher forms of taxa share a common ancestry
Reviewing classification
Taxa may be separated or combined if it is shown that they do/ do not have common ancestry
Advantages of classification
Identification of a species is easier. If a species is not quickly known, its identification can be easier if it can be travelled through the taxonomy classification. Dichotomous keys help with assigning a species to its correct location.
Advantages of classification (2)
Prediction of characteristics. Those in similar taxonomy can be predicted to have similar characteristics. Bats can be predicted to have hair, a placenta, a four-chamber heart and other mammalian properties because it is a mammal. If bats were classified with other animals like birds because they both fly, their characteristics could not be predicted with such accuracy.
Dichotomous keys
Numbered series of pairs of descriptions. Numbers lead to elsewhere on the keys. (Page 265)
Used to identify a species.
Bryophyta
Vegetative organs -
Rhizoids, but not long roots. Some only have simple shoots and leaves, others only have a thallus
Vascular tissue -
No xylem or phloem
Cambium -
No cambium, true trees and shrubs
Pollen -
No
Ovules -
No
Seeds -
No
Fruits -
No
Filicinophyta
Vegetative organs -
leaves, roots, and shoots are present
Vascular tissue -
Contains xylem and phloem
Cambium -
No cambium, true trees and shrubs
Pollen -
No
Ovules -
No
Seeds -
No
Fruits -
No
Coniferophyta
Vegetative organs -
leaves, roots, and shoots are present
Vascular tissue -
Contains xylem and phloem
Cambium -
Present, allowing secondary thickening of roots and shoots and development into trees and shrubs
Pollen -
Present in males
Ovules -
Present in females
Seeds -
Produced and dispersed
Fruits -
No
Angiospermatophyta
Vegetative organs -
leaves, roots, and shoots are present
Vascular tissue -
Contains xylem and phloem
Cambium -
Present in some; allows for secondary thickening of shoots and roots and development into trees and shrubs
Pollen -
Produced by Anthers in flower
Ovules -
Produced and kept in Ovary in flowers
Seeds -
Produced and dispersed
Fruits -
Produced for dispersion of seeds (via winds, animals etc)
Vegetative organs
Organs that are concerned more with growth than reproduction.
Examples - Roots, shoots and leaves
Vascular tissue
Tissue that is responsible for transport within the plant
Examples - Phloem and xylem
Cambium
Cells between vascular tissue that can produce more vascular tissue
Ovules
Contains a female gamete, develops into a seed after fertilisation
Pollen
Small structures that contain male gametes that are dispersed
Seeds
Dispersible unit containing the embryo, food reserves, and a seed coat.
Fruits
Seeds together with fruit wall developed by the ovary
Porifera
Examples -
Sponges
Mouth/anus -
None
Symmetry -
None
Skeleton - Internal spicules (skeletal needles)
Other external recognition features -
Many pores for taking in water for food filtering
Cnidaria
Examples, Mouth/Anus, Symmetry, Skeleton, Other external features
Examples -
hydras, jellyfish, anemones, corals
Mouth/anus -
Mouth
Symmetry -
Radial
Skeleton -
Soft, but hard corals secrete CaCO₃
Other external recognition features -
Tentacles arrange din rings around the mouth, stinging cells
Platyhelminthes
Examples, Mouth/Anus, Symmetry, Skeleton, Other external features
Examples -
Flatworms, flukes, tapeworms
Mouth/anus -
Mouth
Symmetry -
Bilaterally
Skeleton -
No, soft bodies
Other external recognition features -
Flat and thin bodies in the shape of a ribbon, no blood or gas exchange system
Mollusca
Examples, Mouth/Anus, Symmetry, Skeleton, Other external features
Examples -
Gastropods (snails and slugs), bivalves, chitons, squids, octopi
Mouth/anus -
Both
Symmetry -
Bilaterally
Skeleton -
Most have shells made of CaCO₃
Other external recognition features -
Fold in the body wall (mantle) secretes the shell. The hard rasping radula is used for feeding
Annelida
Examples, Mouth/Anus, Symmetry, Skeleton, Other external features
Examples -
Marine bristle worm, Oligochaetes (earthworms), and leeches
Mouth/anus -
Both
Symmetry -
Bilaterally
Skeleton -
Internal cavity with fluid under pressure
Other external recognition features -
Bodies made of many ring-shaped segments often with bristles. Blood vessels often visible.
Arthropoda
Examples, Mouth/Anus, Symmetry, Skeleton, Other external features
Examples -
Crustaceans (krill, barnacles, shrimp, lobsters woodlice, crabs, etc), insects, myriapods (centipede etc), arachnids.
Mouth/anus -
Both
Symmetry -
Bilaterally
Skeleton -
External skeletons made by chitin
Other external recognition features -
Segmented bodies with legs and other appendages separated by joints
Fish
Outer layer, gas exchange system, limbs, appendages, fertilisation, young, (no clue what to name), body temperature
Outer layer -
Scales: bony plates on skins
Gas exchange system -
Gills covered by an operculum and with a single gill slit
Limbs -
None
Appendages used for movement -
Fins supported by rays
Fertilisation -
Eggs and sperm released into water for fertilisation
Young -
Live in water for their whole life cycle
? -
Swim bladder contains gas which assist with buoyancy.
Body temperature -
Do not maintain the internal temperature
Amphibians
Outer layer, gas exchange system, limbs, appendages, fertilisation, young, (no clue what to name), body temperature
Outer layer -
Soft moist skin which is permeable to water and gases
Gas exchange system -
Small lungs with small folds and moist skin for gas exchange
Limbs -
Tetrapods with pentadactyl limbs
Appendages used for movement -
4 legs
Fertilisation -
Sperm and egg released for fertilisation
Young -
Larval begin their life in water, adults often live on land.
? -
Eggs surrounded by protective jelly
Body temperature -
Do not maintain internal temperature
Reptiles
Outer layer, gas exchange system, limbs, appendages, fertilisation, young, (no clue what to name), body temperature
Outer layer -
Impermeable skin made of scales made of keratin
Gas exchange system -
Lungs with extensive folding for increased surface area for gas exchange
Limbs -
Tetrapods with pentadactyl limbs
Appendages used for movement - 4 legs (mostly)
Fertilisation -
Sperm is entered into the female internally
Young -
Eggs are coated in a soft shell
? -
Teeth of all one type, no living parts to them
Body temperature -
Do not maintain internal temperature
Birds
Outer layer, gas exchange system, limbs, appendages, fertilisation, young, (no clue what to name), body temperature
Outer layer -
Skin with feathers made of keratin
Gas exchange system -
Lungs with para-bronchial folds and air sacs (to ventilate)
Limbs -
Tetrapods with pentadactyl limbs
Appendages used for movement -
2 legs, 2 wings
Fertilisation -
Sperm is entered into the female internally
Young -
Eggs are coated with a hard shell
? -
Beak, no teeth
Body temperature -
Maintains internal temperature
Mammals
(Outer layer, Gas exchange system, Limbs, Appendages used for movement, Fertilisation, Young, (not sure what to name this one), Body temperature)
Outer layer -
Skin and hair created from keratin
Gas exchange system -
Lungs with alveoli, ventilated using ribs and diaphragm
Limbs -
Tetrapods with pentadactyl limbs
Appendages used for movement -
4 legs or 2 legs with 2 wings/arms
Fertilisation -
Sperm is entered into the female internally
Young - young are produced that develop with the mother’s aid (mammary glands produce milk)
? -
Teeth with different types, contain a living core
Body temperature -
Maintain internal temperature
rRNA
Ribosomal RNA - this is what ribosomes are made from. This is why ribosomes are not counted as organelles (only made from folded rRNA)
