Question

The DNA double helix of watson and crick model of DNA double helix is
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Answer 1

Answer:

Watson-Crick Structure of DNA. Deoxyribonucleic Acid (DNA) is a double-stranded, helical molecule. It consists of two sugar-phosphate backbones on the outside, held together by hydrogen bonds between pairs of nitrogenous bases on the inside.

Answer 2

Explanation:

ɪɴ ᴘʀᴏᴋᴀʀʏᴏᴛᴇs, sᴜᴄʜ ᴀs, ᴇ. ᴄᴏʟɪ, ᴛʜᴏᴜɢʜ ᴛʜᴇʏ ᴅᴏ ɴᴏᴛ ʜᴀᴠᴇ ᴀ ᴅᴇғɪɴᴇᴅ ɴᴜᴄʟᴇᴜs, ᴛʜᴇ ᴅɴᴀ ɪs ɴᴏᴛ sᴄᴀᴛᴛᴇʀᴇᴅ ᴛʜʀᴏᴜɢʜᴏᴜᴛ ᴛʜᴇ ᴄᴇʟʟ. ᴅɴᴀ (ʙᴇɪɴɢ ɴᴇɢᴀᴛɪᴠᴇʟʏ ᴄʜᴀʀɢᴇᴅ)ɪs ʜᴇʟᴅ ᴡɪᴛʜ sᴏᴍᴇ ᴘʀᴏᴛᴇɪɴs (ᴛʜᴀᴛ ʜᴀᴠᴇ ᴘᴏsɪᴛɪᴠᴇ ᴄʜᴀʀɢᴇs) ɪɴ ᴀ ʀᴇɢɪᴏɴ ᴛᴇʀᴍᴇᴅ ᴀs ‘ɴᴜᴄʟᴇᴏɪᴅ’. ᴛʜᴇ ᴅɴᴀ ɪɴ ɴᴜᴄʟᴇᴏɪᴅ ɪs ᴏʀɢᴀɴɪsᴇᴅ ɪɴ ʟᴀʀɢᴇ ʟᴏᴏᴘs ʜᴇʟᴅ ʙʏ ᴘʀᴏᴛᴇɪɴs.

ɪɴ ᴇᴜᴋᴀʀʏᴏᴛᴇs, ᴛʜɪs ᴏʀɢᴀɴɪsᴀᴛɪᴏɴ ɪs ᴍᴜᴄʜ ᴍᴏʀᴇ ᴄᴏᴍᴘʟᴇx. ᴛʜᴇʀᴇ ɪs ᴀ sᴇᴛ ᴏғ ᴘᴏsɪᴛɪᴠᴇʟʏ ᴄʜᴀʀɢᴇᴅ, ʙᴀsɪᴄ ᴘʀᴏᴛᴇɪɴs ᴄᴀʟʟᴇᴅ ʜɪsᴛᴏɴᴇs. ᴀ ᴘʀᴏᴛᴇɪɴ ᴀᴄǫᴜɪʀᴇs ᴄʜᴀʀɢᴇ

ᴅᴇᴘᴇɴᴅɪɴɢ ᴜᴘᴏɴ ᴛʜᴇ ᴀʙᴜɴᴅᴀɴᴄᴇ ᴏғ ᴀᴍɪɴᴏ ᴀᴄɪᴅs ʀᴇsɪᴅᴜᴇs ᴡɪᴛʜ ᴄʜᴀʀɢᴇᴅ sɪᴅᴇ ᴄʜᴀɪɴs. ʜɪsᴛᴏɴᴇs ᴀʀᴇ ʀɪᴄʜ ɪɴ ᴛʜᴇ ʙᴀsɪᴄ ᴀᴍɪɴᴏ ᴀᴄɪᴅ ʀᴇsɪᴅᴜᴇs ʟʏsɪɴᴇ ᴀɴᴅ ᴀʀɢɪɴɪɴᴇ.

ʙᴏᴛʜ ᴛʜᴇ ᴀᴍɪɴᴏ ᴀᴄɪᴅ ʀᴇsɪᴅᴜᴇs ᴄᴀʀʀʏ ᴘᴏsɪᴛɪᴠᴇ ᴄʜᴀʀɢᴇs ɪɴ ᴛʜᴇɪʀ sɪᴅᴇ ᴄʜᴀɪɴs. ʜɪsᴛᴏɴᴇs ᴀʀᴇ ᴏʀɢᴀɴɪsᴇᴅ ᴛᴏ ғᴏʀᴍ ᴀ ᴜɴɪᴛ ᴏғ ᴇɪɢʜᴛ ᴍᴏʟᴇᴄᴜʟᴇs ᴄᴀʟʟᴇᴅ ʜɪsᴛᴏɴᴇ ᴏᴄᴛᴀᴍᴇʀ.

ᴛʜᴇ ɴᴇɢᴀᴛɪᴠᴇʟʏ ᴄʜᴀʀɢᴇᴅ ᴅɴᴀ ɪs ᴡʀᴀᴘᴘᴇᴅ ᴀʀᴏᴜɴᴅ ᴛʜᴇ ᴘᴏsɪᴛɪᴠᴇʟʏ ᴄʜᴀʀɢᴇᴅʜɪsᴛᴏɴᴇ ᴏᴄᴛᴀᴍᴇʀ ᴛᴏ ғᴏʀᴍ ᴀ sᴛʀᴜᴄᴛᴜʀᴇ ᴄᴀʟʟᴇᴅ ɴᴜᴄʟᴇᴏsᴏᴍᴇ . ᴀ ᴛʏᴘɪᴄᴀʟ ɴᴜᴄʟᴇᴏsᴏᴍᴇ ᴄᴏɴᴛᴀɪɴs 200 ʙᴘ ᴏғ ᴅɴᴀ ʜᴇʟɪx. ɴᴜᴄʟᴇᴏsᴏᴍᴇs ᴄᴏɴsᴛɪᴛᴜᴛᴇ ᴛʜᴇ ʀᴇᴘᴇᴀᴛɪɴɢ ᴜɴɪᴛ ᴏғ ᴀ sᴛʀᴜᴄᴛᴜʀᴇ ɪɴ ɴᴜᴄʟᴇᴜs ᴄᴀʟʟᴇᴅ ᴄʜʀᴏᴍᴀᴛɪɴ, ᴛʜʀᴇᴀᴅ- ʟɪᴋᴇ sᴛᴀɪɴᴇᴅ (ᴄᴏʟᴏᴜʀᴇᴅ) ʙᴏᴅɪᴇs sᴇᴇɴ ɪɴ ɴᴜᴄʟᴇᴜs. ᴛʜᴇ ɴᴜᴄʟᴇᴏsᴏᴍᴇs ɪɴ ᴄʜʀᴏᴍᴀᴛɪɴ ᴀʀᴇ sᴇᴇɴ ᴀs ‘ʙᴇᴀᴅs-ᴏɴ-sᴛʀɪɴɢ’ sᴛʀᴜᴄᴛᴜʀᴇ ᴡʜᴇɴ ᴠɪᴇᴡᴇᴅ ᴜɴᴅᴇʀ ᴇʟᴇᴄᴛʀᴏɴ ᴍɪᴄʀᴏsᴄᴏᴘᴇ (ᴇᴍ).

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