Chapter 1 - Characteristics and classification of living organisms Flashcards
What is movement?
Movement is an action by an organism or part of an organism causing a change of position or place.
What is respiration?
Respiration is the chemical reactions in cells that break down nutrient molecules and release energy for metabolism.
What is sensitivity?
Sensitivity is the ability to detect and respond to changes in the internal or external environment.
What is growth?
Growth is a permanent increase in size and dry mass.
What is reproduction?
Reproduction is the process that makes more of the same kind of organism.
What is excretion?
Excretion is the removal of waste products of metabolism and substances in excess of requirements.
What is nutrition?
Nutrition is the taking in of materials for energy, growth and development
How are organisms classified?
Organisms can be classified into groups by the features that they share. Classification systems aim to reflect evolutionary relationships between species. Organisms share features because they originally descend from a common ancestor.
What is a species?
Species is a group of organisms that can reproduce to produce fertile offspring.
What is the order of the binomial system?
The binomial system is an internationally agreed system in which the scientific name of an organism is made up of two parts showing the genus and the species. Kingdom -> Phylum -> Class -> Order -> Family -> Genus -> Species
What are dichotomous keys?
Dichotomous keys are used to identify organisms based on a series of questions about their features
How are the sequences of bases in DNA used to classify organisms?
The sequences of bases in DNA is used to classify organisms. E.g. the more similar the base sequences in the DNA of two species, the more closely related those two species are (and the more recent in time their common ancestor is). These organisms will be more similar to each other than those who only share a distant ancestor.
What are the five kingdoms?
The five kingdoms are: animals, plants, fungi, protoctista and prokaryotes
What are animals?
Animals are multicellular, their cells contain a nucleus, but NO cell walls or chloroplasts and they feed on organic substances made by other living things.
What are plants?
Plants are multicellular, their cells contain a nucleus, chloroplasts, and cellulose cell walls and they all feed by photosynthesis.
What are fungi?
Fungi (moulds, mushrooms, yeast) are usually multicellular, their cells have nuclei and cell walls made from chitin and they feed by saprophytic (dead or decaying material) or parasitic nutrition (on living material)
What are protoctista?
Protoctista (amoeba, paramecium, plasmodium) are mostly unicellular, but some are multicellular, they all have a nucleus, some may have cell walls and chloroplasts, and this means that some protoctista photosynthesise and some feed on organic substances made by other living organisms.
What are prokaryotes?
Prokaryotes (bacteria, blue-green algae) are often unicellular, and cells have cell walls made from peptidoglycan and cytoplasm but no nucleus or mitochondria.
What are vertebrates?
Vertebrates are animals that have a backbone and can be classified into mammals, birds, reptiles, amphibians and fish.
What are mammals?
Mammals (horse, dog, squirrel, human) have fur/hair on skin, have a placenta, their young feed on milk from mammary glands, they have external ears that are visible, and they are endothermic.
What are birds?
Birds (parrot, blue tit, eagle) have skin covered in feathers, they have 2 legs and 2 wings, they lay eggs with hard shells on land, they have a beak, and they are endothermic.
What are reptiles?
Reptiles (snake, turtle, iguana) have dry, fixed scales on skin and lay eggs with rubbery shells on land.
What are amphibians?
Amphibians (frog, toad, newt) have smooth, moist skin, the adults usually live on land (so have lungs), however larvae live in water (so have gills) and they lay eggs in water without shells.
What are fish?
Fish (flounder, grouper) have loose, wet scales on skin, have gills to breathe and lay eggs without shells in water.
