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Nucleotide

The building block of a nucleic acid, consisting of a five-carbon sugar covalently bonded to a nitrogenous bas and a phosphate group.

Bases

compounds that reduce the concentration of hydrogen ions in a solution

Structure of DNA

double helix, long molecule made up of nucleotides

Base Pairing

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.

RNA

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

Protein Synthesis

the formation of proteins by using information contained in DNA and carried by mRNA

Transcription

(genetics) the organic process whereby the DNA sequence in a gene is copied into mRNA

Translation

(genetics) the process whereby genetic information coded in messenger RNA directs the formation of a specific protein at a ribosome in the cytoplasm

Genetic Code

the ordering of nucleotides in DNA molecules that carries the genetic information in living cells

Taxonomy

(biology) study of the general principles of scientific classification

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.

Seven terms of Classification

domain,kindom,phylum,class,order,family,genus, and species

Binomial nomenclature

Classification system in which each species is assigned a two-part scientific name

Who invented Binomial nomenclature

Swedish botanist -- Carolus Linnaeus

The six kingdoms

archeabacteria, eubacteria, protista, fungi, plantae, animalia

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

Prokaryotic

having cells that lack membrane-bound nuclei

Pathogen

any disease-producing agent (especially a virus or bacterium or other microorganism)

Heterotrophs

organisms that cant make their own food

Autotrophs

organisms that make their own food

Saprophytes

Organisms that obtain their food from dead organic matter (plant and animal material)

Endotoxins

Toxic substances made of lipids and carbohydrates associated with the outer membrane of Gram-negative bacteria, such as E. coli.

Exotoxins

proteins produced during bacterial metabolism

Whats worse Exotoxins or Endotoxins

Endotoxins

Obligate Anaerobes

Organisms that cannot live where molecular oxygen is present.

Obligate Aerobes

prokaryotes that need oxygen to live

Facultative bacteria

Can suvive in oxygen and without oxygen.

Binary fusion

division of a prokaryotic cell into two offspring

Parenchyma

animal tissue that constitutes the essential part of an organ as contrasted with e.g. connective tissue and blood vessels

Collenchyma

type of ground tissue cell with a strong, flexible cell wall; helps support larger plants

Sclerenchyma

type of ground-tissue cell with an extremely thick, rigid cell wall that makes ground tissue tough and strong

Apical

layer of epithelium that dictates the name of its shape

Lateral

body parts away from the midline

Xylem

the woody part of plants: the supporting and water-conducting tissue, consisting primarily of tracheids and vessels

Phloem

vascular tissue responsible for the transport of nutrients and the carbohydrates produced by photosynthesis

Roots function

absorbs water & minerals from the ground

Types of roots

taproot system (lateral roots) and fibrous root system

Annual rings

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.

Capillarity

the attraction between molecules that results in the rise of the surface of a liquid when in contact with a solid

Leaves functions

photosynthesis, transpiration

gas exchange

The uptake of molecular oxygen from the environment and the discharge of carbon dioxide to the environment

Gametes

Reproductive Cells

Whorls

sepal, petals, stamens, carpel

methods of pollination

self-pollination and cross-pollination

Fertilization process

One of the cells in the pollen grain fertilizes endosperm mother cell and forms endosperm, the other fertilizes an egg and forms a zygote

Seed dispersal

scattering of seeds; can be done by animals, insects, air, or water

Conditions for germination

Proper temperature, sufficient oxygen for respiration, moisture

Asexual Reproduction

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)

trochopores

the free swimming larvae of mollusks

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

what does Mollusks mean

soft-bodied animals

What does Annelids mean

little rings

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