3&4. Funamental Structure Of Livign Things ( Finish)

Question 1

What elements is life made up of ? (Acronym)

Answer 1

(Chnops j
Carbon,hydrogen, nitrogen(amino acids dna ), oxygen, phosphorus (dna ,atp), sulfur (amino acids )

Question 2

Why is carbon base for life and silicon not?

Answer 2

Carbon forms complex chains with useful elements,
Silicon forms SiO4 w oxygen tetrahedral structure bc larger very stable but is rocks
Forms unstable compounds w other elements

Question 3

What are proteins and what they used for?

Answer 3

-constructed from amino acids in dehydration reaction forming peptide link

Question 4

What is chirlaity?

Answer 4

Non super imposable mirror images,
L-amino acids (left handed) except glycine
Sugar right handed

Question 5

What are sugars used for?

Answer 5

Storage and transport of energy

Question 6

What is a lipid and what’s it used for?

Answer 6

Complex carbon compounds often used in cell membranes,
Store energy

Question 7

What is an example of nucleic acid?

Answer 7

DNA

Question 8

What are the 4 dna bases and what are there pairs?

Answer 8

A,T,CG
A binds with T
C binds with G

Question 9

Definition of DNA

Answer 9

A backbone made of alternating phosphate and ribose sugar

Question 10

Why is water essential for life?

Answer 10

Medium for chemical reactions.carries nutrients and energy supplies, maintains thermal balamce

Question 11

Why are the advantages of using water for life?

Answer 11

Readily dissolves many ions, large heat capacity , cosmically abundant , liquid has large temp range

Question 12

Why could ammonia also be a good liquid for life and what is it’s limiting factor?

Answer 12

Dissolves ion, large heat capacity, allow for ammonia based bonds to make long chains ,
less viscous than water
BUT narrower liquid temp range

Question 13

Major features of cell?

Answer 13

Energy system, information system, membrane

Question 14

What are the two types of cell and main differences?

Answer 14

Prokaryotes ( no nucleus) , all bacteria and archea, small
Eukaryotes (nucleus to encapsulate dna), larger,organelles that compartmentalise eg chloroplqsts

Question 15

Key features of phospholipids?

Answer 15

Made of phosphate group and fatty acids tails, the phosphate group is hydrophilic so likes water and the fatty acid tails are hydrophobic so don’t like water

Question 16

How do phospholipids self assemble to form membranes and other structures?

Answer 16

When put in water the hydrophobic tails move together to to escape the water molecules, this forms lipid bilayer. Two rows with hydrophobic tails on the inside and hydrophilic heads on outside creating a water proof insoluble barrrier

Question 17

What’s the difference between rna and dna?

Answer 17

DNA, double stranded, deoxyribose sugar, bases C,G,A,T
RNA, single stranded, ribose sugar, CGAU

Question 18

How does transcription of DNA work?

Answer 18

RNA polymerase unwinds DNA sequence,
mRNA forms base pairs with DNA (C-G, A-U)
mRNA carries info to ribosome

Question 19

What happens in translation stage of DNA?

Answer 19

mRNA is on a ribosome and transfer RNA brings amino acids to ribosome
The tRNA has one end bound to amino acid and one end to anticodon of three bases
tRNA lines up amino acids using mRNA code
Every group of of 3 mRNA bases “codon” encode a single amino acid