Bio t2

Why is osmosis important

Important to regulate the amount of water inside plant and animal cells

isotonic

If the animal cell in an environment that has the same water potential as inside the cell there is no change-said to be normal. Same for plant cell.

Hypotonic

If the animal cell in an environment has higher water potential than inside the cell water will enter the cell moving down the concentration gradient-will swell and lyse(burst). In plant cell will swell but wont burst.

Hypertonic

If the animal cells in an environment is lower than water potential than inside the cell and will shrivel. In plant cell will shrivel up and membrane pulls away from cell wall.

Active transport

Movement of molecules/ions in our out of a cell through the cell membrane against a concentration gradient

Diploid

2 sets of chromosomes
produced by mitosis
body cells(somatic)

Haploid

one set of chromosomes
produced by meiosis
Gamates

Protein synthesis step 1

A complementary template of a gene is made called mRNA
Process is called transcription

Protein synthesis step 2

The mRNA moves from the nucleus to the cytoplasm of the cell

Protein synthesis step 3

mRNA attaches to a ribosome

Protein synthesis step 4

Ribosome reads the mRNA in sets of three bases called codons and attach tRNA that have complementary sequence called an anti-colon to it. The tRNAs are attached to amino acids
Process called translation

Protein synthesis step 5

The long sequence of amino acids folds into its final shape

Mutation

A permanent change in the genetic material of an organism caused by mistakes when the DNA is being copied or by mutagens

Cell

Smallest living unit that carries out life activities

Interphase-Mitosis

Normal cell activities and cell replication

Prophase-Mitosis

The DNA condenses and supercoils into chromosomes and nuclear envelope breaks down

Metaphase-Mitosis

Chromosomes are pulled to centre of cell where they line up

Anaphase-Mitosis

Centromeres divide and sister chromatids are separated and pulled to opposite ends of the cell.

Telophase-Mitosis

Chromosomes uncoil

Cytokinesis occurs

Nuclear envelope reforms around chromosomes

Fertilization

Each fertilization is a random independent event and genotype resets after each offspring

Genetic Engineering

Changing the genetic material of an organism by removing, inserting or changing individual gene

Plasmids

small circular pieces of DNA

Biotechnology

The application of science in the direct or indirect use of living organisms

How is penicillin made by penicillium

Scientists learned to grow the penicillium mold in fermenters and then separate it from the mold then purified to make the antibiotic

Advantages of GE

increased nutritional content and crop yields

Disadvantages of GE

Loss in diversity allergic reactions and higher than natural

Levels of toxins

Sexual reproduction

Involves a male gamete and female gamete from 2 parents

Variation

Difference between individuals of the same species

Asexual reproduction

Produces genetically identical offspring involving only 1 parent

Natrual selection

At particular times members of the species that are more suited to the conditions within that ecosystem reproduce and pass on their alleles

Difference between artificial selection and selective breeding

Artificial selection is where human identify features in a species that are desirable and only breed individuals who have those desirable traits. Selective breeding is the selection by breeders for desirable phenotypes and genotypes to produce individuals with specific characteristics and has to continue over many generations.