The building block of a nucleic acid, consisting of a five-carbon sugar covalently bonded to a nitrogenous bas and a phosphate group.
principle that bonds in DNA can form only between adenine and thymine and between guanine and cytosine
Replication of DNA
During this process, each DNA strand of the parental double helix serves as a template for a new strand in a daughter molecule. This process is termed semiconservative replication beause each daughter DNA double helix contains an old strand from the parental DNA double helix and a new strand.
ribonucleic acid, a natural polymer that is present in all living cells and that plays a role in protein synthesis
Three types of RNA
•mRNA = holds the DNA code
•tRNA = brings amino acids to the mRNA
•rRNA = is physically part of ribosome
Differences between DNA and RNA
DNA is double stranded, RNA is single stranded, DNA has deoxyribose sugar and RNA has ribose sugar
the formation of proteins by using information contained in DNA and carried by mRNA
(genetics) the process whereby genetic information coded in messenger RNA directs the formation of a specific protein at a ribosome in the cytoplasm
the ordering of nucleotides in DNA molecules that carries the genetic information in living cells
What do we use to classify organisms?
Scientists examine the creatures cell structure to see if it is prokaryotic or eukaryotic. Prokaryotic organisms are usually simple organisms and eukaryotic ones are complex. For example, humans are eukaryotic. Bacteria is prokaryotic.
Classification system in which each species is assigned a two-part scientific name
Examples of the Six kingdoms
Kingdom Bacteria eg) all true bacteria.
Kingdom Archaea eg) Ancient bacteria, also known as archaebacteria.
kingdom Protista eg) unicellular parasites.
Kingdom Fungi eg) Moulds, yeast, rusts, mushrooms, toadstools.
kingdom Plantae eg) all land plants.
Kingdom Animalia eg) All animals
Difference between Gram + and Gram -
gram - do not retain the stain & appear PINK
gram + bacteria retain the stain & appear PURPLE
Toxic substances made of lipids and carbohydrates associated with the outer membrane of Gram-negative bacteria, such as E. coli.
animal tissue that constitutes the essential part of an organ as contrasted with e.g. connective tissue and blood vessels
type of ground tissue cell with a strong, flexible cell wall; helps support larger plants
type of ground-tissue cell with an extremely thick, rigid cell wall that makes ground tissue tough and strong
the woody part of plants: the supporting and water-conducting tissue, consisting primarily of tracheids and vessels
vascular tissue responsible for the transport of nutrients and the carbohydrates produced by photosynthesis
Rings or layers of wood which represent one growth period of a tree. In cross section the rings may indicate the age of the tree.
the attraction between molecules that results in the rise of the surface of a liquid when in contact with a solid
The uptake of molecular oxygen from the environment and the discharge of carbon dioxide to the environment
One of the cells in the pollen grain fertilizes endosperm mother cell and forms endosperm, the other fertilizes an egg and forms a zygote
reproduction that does not involve the union of gametes and in which a single parent produces offspring that are genetically identical to the parent
Characteristics of mollusks
one or two shells (bivalves), cephalopods (no shells), castropods (one shell), most live in water, open circulatory system, closed circulatory system, have a foot, soft body
Characteristics of annelids
closed circulatory system, body is in segments, digestive system, breath through their skin, found in fresh and saltwater and soil, tube shaped bodies, have setae, bilateral symmetry, body cavity, 2 body openings (mouth, anus)
Classes of Mollusks
Polylpacophora - chiton, Gastropoda - snails & slugs, Bivalvia - clams, oysters, mussels, scallops Cephalpoda - squid & octopus
Classes of Annelids
1. Polychaeta - marine segmented worm
2. Oligochaeta - terrestrial, freshwater => earthworm
3. Hirudinida - leeches