Biology Review Part 3

- Translation/Transcription, Meiosis/Mitosis, Osmosis, Passive/Active Transport

Translation

• mRNA read it’s sequence and translates it into a chain of amino acids

Transcription

• Converts DNA code into an mRNA message

DNA ( deoxyribonucleic acid )

• A molecule that carries the genetic instructions

• Shaped like a twisted ladder = double helix

mRNA ( Messenger RNA )

• Carries genetic information from the nucleus of a cell to the cytoplasm

• essential for gene expression and the production of proteins

tRNA ( Transport RNA )

• small RNA molecule that link mRNA to specific amino acids during protein synthesis

Chromosomes

Mitosis

Meiosis

Cell Membran

• A specialized, semi-permeable barrier → only SOME substances can pass through

Passive Transport

• Diffusion of substances and osmosis

• Molecules move naturally from HIGH to LOW.

• Does NOT need energy

Facilitated Diffusion

Active Transport

• moves molecules from low → high

• opposite of natural process

• NEEDS ENERGY

Endocytosis

INTO cell

Exocytosis

OUT of cell