More biological molecules Flashcards Preview

Biology AS > More biological molecules > Flashcards

Flashcards in More biological molecules Deck (50):
1

What is the function of DNA?

It stores genetic information

2

What are ribosomes made up of?

RNA and proteins

3

Name the monomer of DNA and RNA

Nucleotides

4

What join together to form polynucleotide stands?

(Many) Nucleotides

5

What kind of bond, present in a polynucleic chain, consists of two ester bonds and a phosphate group

Phosphodiester bond

6

Describe 3 differences between DNA and RNA

DNA is double stranded, RNA is single stranded
DNA contains thymine, RNA replaces it with uracil
RNA is relatively short compared to DNA

7

What caused many scientists to doubt that DNA carried the genetic code

DNA has a relatively simple chemical composition

8

DNA and RNA are both types of what acid?

Nucleic acids

9

What is the full name for DNA

Deoxyribonucelic acid

10

What is the full name of RNA

Ribonucleic acid

11

What is the function of RNA

To transfer genetic information from the DNA to the ribosomes

12

What is the function of ribosomes

They read RNA to make polypeptides

13

What are the three components in DNA structure

A phosphate group
A nitrogen containing base
A deoxyribose sugar

14

DNA is copied by semi-conservative replication of DNA. What is meant by this?

It's where half of the new strands of DNA are from the original molecule of DNA

15

Name two enzymes involved in DNA replication

DNA helicase
DNA polymerase

16

Describe the first stage of DNA replication, in which two strands of DNA are separated

DNA helicase breaks the hydrogen bonds between the base pairs on the two polynucleotide DNA strands. This makes the helix unwind to form two single strands

17

Describe the second stage of DNA replication, where the single strands of DNA act as templates

Free floating DNA nucleotides are attracted to their complementary exposed bases in each original template strand

18

Name two examples of processes that plants need energy for

Active transport
DNA replication

19

Name two examples of processes that animals need energy for

DNA replication
Active transport

20

What does ATP stand for?

Adenosine Triphosphate

21

What is the process called in which plants and animals release energy from glucose

Respiration

22

A cell can't get its energy directly from glucose therefore what happens?

The energy released from glucose is used to make ATP

23

Describe the structure of ATP

Nitrogen containing base, adenine
Ribose sugar
3 phosphate groups

24

Why is ATP known as a nucleotide derivative

Because it's a modified form of a nucleotide

25

Where is the energy in ATP stored?

In high energy bonds between the phosphate group

26

When energy is needed by a cell, what happens to ATP?

It gets broken down into ADP and Pi

27

How is energy released during the hydrolysis of ATP?

A phosphate bond is broken, releasing the stored energy

28

What enzyme catalysis the breakdown of ATP?

ATP hydrolase

29

ATP hydrolysis can be coupled to other energy requiring reactions in the cell, what does this mean?

That energy released can be used directly to make the coupled reaction happen

30

How can inorganic phosphate (Pi) be used?

Added to another compound, which makes the compound more reactive

31

What reaction happens when ATP is resynthesised from ADP and Pi?

Condensation

32

Name two examples of processes where ATP resynthesis occurs

Respiration
Photosynthesis

33

What enzyme catalysed ATP resynthesis

ATP synthase

34

Name 4 important functions of water

- it is a metabolite
- it is a solvent
- water molecules are very cohesive
- it helps with temperature control

35

Is water a polar or non-polar molecule?

Polar

36

What are hydrogen bonds?

Weak bonds
Between slightly positively charged hydrogen atom in one molecule and a slightly negatively charged atom in another molecule

37

Name 2 reactions that water is involved in

Condensation
Hydrolysis

38

Why is water classed as a polar molecule?

Because it has a slight positive charge on one side and a slight negative charge on the other

39

What is a metabolite?

A substance involved in metabolic reactions

40

What makes water useful as a solvent?

It's polarity

41

What is cohesion?

The attraction of two molecules of the same type

42

Why is water being a good solvent useful for living organisms?

It means they can take up useful substances dissolved in water and these can be transported around their body

43

In terms of its hydrogen bonds, when does water evaporate

When the hydrogen bonds holding the water molecules together are broken

44

What are ions?

An atom that has an electric charge

45

What is an atom with a positive charge called?

A cation

46

Give an example of a cation

Sodium

47

What is an ion with a negative charge called?

A anion

48

Give an example of an anion

Chlorine

49

What is an inorganic ion

An ion that doesn't contain carbon

50

Give an examples of an inorganic ion

Hydrogen
Sodium