DNA is made of building blocks called nucleotides

DNA is made of building blocks called nucleotides. They consist of a deoxyribose sugar, a phosphate group and a nitrogen base. The bases are adenine, thymine, guanine, and cytosine. Phosphate group Deoxyribose Nitrogen Base

REPLICATION : A matches with T and G matches with C, DNA copies DNA http: //www. johnkyrk. com/DNAreplication. h tml http: //nobelprize. org/ chemistry/educationa l/dna/b/replication/dn a_compounds. html

TRANSCRIPTION: A matches with U and G matches with C, m. RNA copies DNA http: //www. johnkyrk. com/DNAtranscriptio n. html

TRANSLATION: MRNA is decoded and a protein is made from amino acids. Use a chart to decode every three m. RNA bases to see what amino acid the t. RNA’s will carry in to build a protein. http: //www. johnkyrk. com/DNAtranslation. html

MUTATION: Any change in the DNA sequence. If it is a point mutation (one letter is changed), it can change the amino acid sequence by changing the code. ATC ATG Deletion Point mutation

Translation Transcription DNA In nucleus Now you try it: m. RNA On ribosome Protein TACACCGTC 1. Write this DNA base pair sequence on you paper. 2. Write the complementary strand of DNA that would bond to them. 3. Translate the strand into m. RNA. 4. List the amino acids that these codons stand for. Use the amino acid chart on the next slide.

TACACCGTC- A T G G C A G Complementary strand that would form in Replication.

TACACCGTC- A U G G C A G Methionine Peptide Bonds Tryptophan Glutamine DNA m. RNA Amino Acids Transcription Translation

Energy and matter flow through ecosystems Radiant energy from the sun is converted to chemical energy in the form of glucose (sugar) by photosynthesis in the chloroplasts of plant cells. Autotrophs (plants/producers) use this energy in respiration. The plant’s mitochondria take that sugar and break it down into ATP that the plant can use to carry out daily life activities.

Part of the energy produced is stored in chemical bonds of the plant and part of it is released as heat to the environment. Heterotrophs eat these producers. The energy stored in their chemicals bonds is used to carry out daily life functions. Photosynthesis Heat lost through respiration Heat lost through respiration Nutrients returned to environment Producer Primary Consumer Secondary consumer Tertiary consumer Decomposer

Wheat Mouse Snake Owl A food chain, shown above, shows one path the energy can take. A food web is a collection of several food chains, linked together.

A food (or energy) pyramid is another way to represent this information. The pyramid gets its shape from the fact that the greatest amount of energy in the ecosystem is stored in the producers. (There is more grass than grasshoppers, and there are more grasshoppers than frogs. ) There are very few tertiary consumers in ecosystems because it takes a lot of energy feed one.

Toxins(poisons) can build up in the food chain. They are the least concentrated in the producers, but can build up in the bodies of animals as they feed. The higher an animal is on the food pyramid, the more poision he has consumed.

Niche-Animal’s role in the ecosystem. Types of niches: Herbivore-eats only plants/producers, Omnivore-eats both plants and animals, Carnivoreeats consumers only (meat), Predator-hunts, Prey-what is being hunted, Decomposer-usually fungus or bacteria that eat dead material and returns nutrients to the environment (may not be included in food webs and pyramids).

Symbiosis: Organisms can have dependent relationships. Mutualism(+, +)-both or organisms benefit from the relationship. Remoras clean sharks. The remoras get food and protection. The sharks get clean. Commensalism (+, 0) –one organism benefits, the other is not effected. Spanish moss grows on trees receiving light and nutrients from the air. The tree is not helped or harmed. Parasitism(+, -)one organism benefits, the other is harmed. The tick receives food, the dog is bitten.

Barnacles and Whales

Cow and Cattle Egret

Lion and Gazelle

Clownfish and Sea Anemone

Flower and Bumblebee

Dog and Flea

Parents and Children