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BIOSCI 107 > Cell Signalling > Flashcards

Cell Signalling Flashcards

1
Q

What are ligands?

A

Signalling molecules

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2
Q

What do ligands do?

A

They bind onto specific receptors (other molecules)

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3
Q

How does a message carried by the ligand work?

A

Leads to a change in the cell in the activity of a gene, or induce a process like cell division.

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4
Q

What does cell to cell signalling involve?

A

Transmission of a signal from a sending cell to receiving cell

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5
Q

What are the basic 4 categories of chemical signalling?

A

Paracrine
Autocrine
Endocrine
Signalling by direct contact

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6
Q

What is paracrine signalling?

A

Cell communication over a relatively short distance

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7
Q

How does paracrine signalling work?

A

Cells that are near one another communicate through release of chemical messengers;

Ligands can diffuse through the space between cells

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8
Q

When does paracrine normally take place?

A

Used in different tissues and contexts, important in development (spinal cord development)

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9
Q

What is the subtype of paracrine signalling?

A

Synaptic

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10
Q

What is synaptic signalling?

A

Synapse process, the junction between two nerve cells where signal transmission occurs.

Ligands are called neurotransmitters which quickly cross small gap between nerve cells. When they bind onto the receptor, chemical change inside cell happens (often opening ion channel)

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11
Q

What is autocrine signalling?

A

Cell signals itself releasing a ligand that binds to its own receptor

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12
Q

Where can you find autocrine signalling?

A

During development, helping cells take on and reinforce heir correct identities.

Important in cancer (key role of metastasis, spread of cancer from original sight)

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13
Q

What is endocrine signalling?

A

Cells need to transmit signal over a long distance.

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14
Q

Which system does endocrine signalling work very closely with?

A

Cardiovascular system

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15
Q

How does endocrine signalling work?

A

In long distance endocrine signalling, signals are produced by specialised cells and released into the bloodstream which carries them to target cells in distant parts of the body.

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16
Q

What are these signals called which gets made at one place and travel a long distance through blood?

A

Hormones

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17
Q

In humans, where are hormones released from?

A

endocrine glands like thyroid, hypothalamus, pituitary, pancreas, and gonads

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18
Q

What is signalling through cell to cell contact?

A

Gap junctions, tiny channels which allow small signalling molecules called intracellular mediators to diffuse between the two cells.

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19
Q

How does binding of a ligand to a receptor work?

A

Specific ligands bind to specific matching receptor which changes the shape of the receptor allowing transmit of a signal or produce a change inside the cell.

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20
Q

What are the two categories of receptors?

A

Intracellular (membrane bound) receptor

Cell surface receptor

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21
Q

What are intracellular receptors?

A

Found inside the cell in the cytoplasm or nucleus

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22
Q

What are cell surface receptors?

A

Found in the plasma membrane anchored proteins.

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23
Q

Does ligand need to cross the plasma membrane for cell surface receptors?

A

No

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24
Q

What are the 3 domains of cell surface receptors?

A

Extracellular ligand binding domain

Hydrophobic domain

Intracellular domain

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25
Q

What are the three main kinds of cell surface receptors?

A

Ion gated channels

GPCR (G protein coupled receptor)

RTK (recpetor tyrosine kinase)

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26
Q

What are ligand gated channels?

A

Channels which open in response of binding of a ligand

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27
Q

How do channels form?

A

Receptor has a membrane spanning region of hydrophillic (love water) in the middle of the channel.

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28
Q

What does the channel do?

A

Lets ions cross the membrane without through hydrophobic core of the phospholipid bilayer

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29
Q

What is GCPRs?

A

Large family of cell surface receptors with common structure and method of signalling.

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30
Q

What do GCPRs do?

A

Transmit signals INSIDE the cell through a type of protein called G protein.

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31
Q

Example of GCPRs use is?

A

Through scent receptors

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32
Q

When a ligand is NOT present, the GCPR…

A

Waits at the plasma membrane in an inactive state.

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33
Q

Where do the G proteins bind to?

A

Onto the GPCR but bind to GTP nucleotide.

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34
Q

GTP breaks down to form…

A

GDP

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35
Q

When a G protein links to GTP is active/inactive?

A

Active

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36
Q

When a G protein links to GDP is active/inactive?

A

Inactive

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37
Q

Describe how GCPRs work

A

Unbound GCPR is unbound and therefore inactive
G protein is bound to GDP and enzyme is inactive too.

Signal binds to receptor and G protein binds to GTP (turns on) but enzyme is still inactive.

Activated G protein + GTP dissociates, receptor activates the enzyme to do a cellular response

G protein has GTPase activity promoting release from enzyme reverting back to resting state.

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38
Q

What is the first step of cell communication?

A

Reception of signal

First messenger (signal protein) binds to protein receptor

Conformational change to the receptor because of the binding

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39
Q

How does RTK work?

A

At rest, RTK are inactive monomers

Signal molecule (growth factor) binds to RTK, dimerises in membrane (separate monomers stick together now like magnets)

TK of one monomer phosphorylates the other monomer activating both monomers.

Each activated RTK binds to activate specific proteins and anzymes

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40
Q

Ligand gated ion channels how they work?

A

At rest, lgand unbound and gate is closed

Ligand is the signalling molecule and gate opens once it binds onto the channel allowing flow of ions.

Ligand comes of and gate closes back to resting state

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41
Q

Cytosollic or nuclear recpetors are what relationship with water and why?

A

Hyrdrophilic as they need to pass the hydrophillic plasma membrane which was made out of phospholipids, lipid soluable or small

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42
Q

What two types of cells are there?

A

Prokaryotic

Eukaryotic

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43
Q

What characteristics does each cell have?

A 
DNA (heritable material) 
RNA (messenger intermediate)
Proteins (as the workers) 
ATP (energy source)
Has a relationship between DNA, RNA and proteins
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44
Q

What are membrane-bound organelles?

A

Organelles protected by a single or double plasma membrane.

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45
Q

What is the difference between the shape of DNA in eukaryote and prokaryotes?

A

EU - Linear double helix

PR - Circular

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46
Q

What do they eu and pro have in common?

A

Have cytoplasm enclosing them both

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47
Q

In pro, where is DNA stored?

A

No nucleus so it’s in nuclear area (nucleoid)

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48
Q

Structure of phospholipids are

A

Double layer of fats called phospholipids

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49
Q

WHat is a phospholipid?

A

Each layer made up of a hydrophilic head and hydrophobic tail with proteins embedded in it

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50
Q

What is the function of the plasma membrane?

A

as a barrier to control entry and exit into the cell semipermeable

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51
Q

What 3 forms of the protein can be found in the plasma membrane?

A

Transmembrane
Peripheral membrane
Glycoprotein

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52
Q

Structure of phospholipids which make up the plasma membrane is?

A

Heads out tails in

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53
Q

What is the function of embedded proteins?

A

mediate movement of hydrophilic substances and intercellular communication

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54
Q

What is the structure of transmembrane protein?

A

Spans the entire membrane, integral protein

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55
Q

What are the 6 different functions of plasma membrane?

A 
Transport
Enzyme activity 
Cell-cell recognition signalling 
Signal transduction 
Intercellular joining
Attachment to the cytoskeleton and ECM
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56
Q

What is an important feature of the plasma membrane?

A

We have to understand the fluidity of the plasma membrane

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57
Q

Name the organelles with a double lipid bilayer

A

Nucleus

Mitochondria

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58
Q

Describe the endomembrane system

A

Transport vesicle from the rough ER is in a transport vesicle which enters the golgi apparatus to modify entering in the cis face and exiting through the trans face and is either secrete out of the cytosol. secreted for membrane renewal or enzyme for cytosol

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59
Q

How is DNA organised and coiled within the nucleus to form a chromosome?

A

8 histone proteins make a nucelosome where the DNA is wrapped around the nucelosome 2x (10nm)

During early mitosis, chromatin condense to chromatin fibre which is 30nm

Fibres condense into loops which are 300nm

Finally form chromosomes held centrally at the centromere 1400nm

DNA can be divided into genes located along teh chromosome (genses codes for proteins via transcription and translation)

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60
Q

Describe what DNA is

A

DNA is a double helix polymer made of many monomers. These monomers are called nucleotides/

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61
Q

What does a nucelotide contain?

A

A phosphate group
Nitrogenous Base
Sugar (deoxyribose)

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62
Q

How is the DNA stabilsied? What bonds

A

Hydrogen bonds (at the bases attachment) and phosphodiester bonds at the chain

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63
Q

What would go wrong if there was an issue with lysosome?

A

Loss of autophagy, autolysis + cellular digestion

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64
Q

What would go wrong if there was an issue with mitochondira?

A

RIP powerhouse of the cell

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65
Q

What would go wrong if there was an issue with golgi appararatus

A

Inability to modify MEMBRANE, ORGANELLE and SECRETED PROTEINS + effect on lysosomes

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66
Q

What would go wrong if there was an issue with smooth ER?

A

Can’t produce carbohydrates and lipids + tissue specific effects i.e. loss of detoxifying enzymes in the liver/loss of calcium stores in muscle

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67
Q

Is a glucose a source of energy?

A

no it isnt the SOLE source of energy

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68
Q

What do complex molecules do?

A

The store energy

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69
Q

What are the steps for gene expression?

A

DNA (transcription)
Pre-mRNA (mRNA processing)
Mature mRNA (transition)
Protein (folding post transition modifications)

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70
Q

What are the sub types of transcription?

A

Initiation
Elongation
Termination

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71
Q

What are the steps of mRNA maturation?

A

5’ cap
Poly A tail
mRNA splicing

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72
Q

What are the subtypes of translation?

A

Initiation
Elongation
Termination

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73
Q

What is happening in transcription?

A

RNA copy segment of DNA

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74
Q

What is happening in maturation of mRNA?

A

Also called mRNA processing

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75
Q

What is happening in translation?

A

Protein production using mRNA template

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76
Q

What is the first step of initiation in transcription?

A

DNA is double stranded (5 to 3 on one strand and 3 - 5 on the other, only ONE will be the template strand)

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77
Q

What is the 2step of initiation in transcription?

A

Upstream (3 to 5) of the gene. is the promoter which usually includes the TATA box with sequence 5- TATAAAA 3)

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78
Q

What is the 3step of initiation in transcription?

A

Transcription factors bind to the promoter specifiaclly to the TATA box

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79
Q

What is the 4step of initiation in transcription?

A

RNA II polymerase is then able to bind to the transcription factors and the START CODON on the DNA

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80
Q

What is the 5step of initiation in transcription?

A

RNA II polymerase undertakes transcription moving from 3 to 5 along template strand and manufacturing the mRNA in 5 to 4 direction

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81
Q

what is the 6step of initiation in transcription?

A

Transcription includes both translate and non translated sequences of

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82
Q

Which direction do proteins work in?

A

5 to 3 direction

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83
Q

What is the nucleus lined by?

A

Nuclear lamina

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84
Q

How do substances enter and exit the nucleus?

A

through the nuclear pore

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85
Q

What is the primary function of the nucleus?

A

House and store DNA

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86
Q

What is the other function of the nucleus?

A

rRNA and ribosome production

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87
Q

What is the cytoplasm?

A

Any part of the cell interior to the plasma membrane

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88
Q

What is the cytoplasm surrounded by?

A

Cytosol a jelly-like substance

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89
Q

What can be found in the cytoplasm?

A 
Nucleus 
Ribosomes
Lysosomes
Mitochondria
ER (smooth and rough) 
Golgi complex
Cytoskeleton
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90
Q

Where is DNA found?

A

Nucleus

91
Q

What is the structure of DNA?

A

Made up of nucleotides

92
Q

What kind of bonds found between the bases?

A

H bonds

93
Q

What is a chromosome?

A

A piece of DNA many genes

94
Q

What is a gene?

A

Section of DNA with known function

95
Q

What is the levels of the appearance of DNA?

A

DNA wrapped 2x around 8 histones = 1 nucleosome 10nm
Many nucleosomes = chromatin

Chromatin condenses further into chromatin fibre 30nm

Chromatin fibre condense coiled up even more to become chromatid 300nm

2 chromatids become a chromosome 1400nm

96
Q

What are pyrimidines?

A

One ring
Cytosine
Thymine
Uracil

97
Q

What are purines?

A

2 rings
Adenine
Guanine

98
Q

What types of sugars are there?

A

Deoxyribose (DNA)

Ribose (RNA)

99
Q

What is the structure of ribosomes?

A

Small and large subunit

100
Q

Where can ribosomes be produced?

A

Nucleolus

101
Q

How are ribosomes made?

A

Made with rRNA proteins from RNA

102
Q

What is the function of ribosomes?

A

Protein production

103
Q

Where can ribosomes be found?

A

Free in cytoplasm

Attached in the ER (rough)

104
Q

How are these proteins modified?

A

In the cytoplasm

105
Q

What is the function of bound ER ribosomes?

A

Production of membrane protein or rotein for use in specific organelles secrete proteins

106
Q

How are these proteins from the ER modified?

A

In the golgi apparatus

107
Q

Where is cholestrol found?

A

In the hydrophobic tails

108
Q

Why do we need cholesterol ?

A

To hold membrane together

109
Q

What happens when a membrane is heated up?

A

Cholestrol holds it togehter

110
Q

What happens when we cool the membrane?

A

Fluidity of membrane is altered by aount of cholestrerol

111
Q

Where is cholesterol made?

A

In the liver

112
Q

What is phosphatdylcholine?

A

Choline, phosphate 4 glycerol
Found outside cell
Chraged area

113
Q

What is programmed cell death?

A

Apoptosis
Phosphatidylcholine folds in 4 the layer underneath it (phosphatidylserine) end up on the outside
Annexin 5 binds to increase and the cell dies

114
Q

Where does apoptosis happen?

A

In the liver

115
Q

Where does apoptosis not happen?

A

Stem cells

Female germline eg. ovaries

116
Q

What are 2dry functions of the nucleus?

A

rRNA and ribosome prod

Compartmentalisation so molecules can be segregated

117
Q

What is the function of histones (nucleosome?

A

Uncoiled DNA for transcription and translation carry epigenetic marks

118
Q

Epigenetics is used for?

A

predict dis-eases

119
Q

How often do cells divide?

A

Most cells every 12 hours

Early embryos every 24 hours

Some cells do not divide like neural stem cell

120
Q

What causes skin cancer?

A

Formation of thymine dimers in DNA when exposed to UV light

121
Q

When are ribosomes mature?

A

Can be used after pushed out from the nuclear pore

122
Q

What happens if lysosome bursts?

A

cell dies

123
Q

How does lysosome digest?

A

Autophagy vesicle and lysosome fuse

124
Q

What is the structure of the ER?

A

An extensive network of tubules and tubules

125
Q

Where is the rough ER?

A

Stretch out from the nuclear membrane

126
Q

Where is the smooth ER

A

extends out from the rough ER

127
Q

What is the function of the rough ER

A

processing packaging sorting

128
Q

What kinds of proteins enter the rough ER?

A

secreted proteins
membrane proteins
proteins due to work in specific organelles

129
Q

What do the proteins look like after it has been in the ER rough?

A

Has a vescile surrounding it goes to golgi

130
Q

What is the function of the smooth ?

A

Housing unit for tissure specidc proteins and enzymes site of production of lipids and carbs in cell

131
Q

What can stored enzymes proteins be used for?

A

In the liver to detox ify drugs or harmul substances

132
Q

What is the structure of golgi?

A

A number of flattened membranous cisternae all stacked on top of each other in a c wifi shape

133
Q

What is the function of golgi?

A

Modify sort package and transport proteins from the rough ER

134
Q

What do the sacs of cisternae contain?

A

Diff enzymes of diff function

135
Q

What is the role of medial cisternae?

A

Modify proteins for function or destination

136
Q

What is the role of cis face?

A

Vesicle from rough ER is enter over here

137
Q

What is the role of trans face?

A

exit cisternae modifies if neccessary package the protein to its destination

138
Q

What is the structure of the lysosomes?

A

Vesicles (bubble) formed from golgi complex

139
Q

What does lysosome contain

A

Digestive enzymes and hydrolytic powerful enzymes

140
Q

What is lysosomes surrounded by

A

plasma membrane of the plasma membrane of golgi

141
Q

What is the function of the proteins found inside of the plasma membrane

A

pumps H+ inside from cytoplasm

allows enzymes to function in the lysosome

142
Q

What is the function of lysosome?

A 
Digestion of 
substances that enter a cell 
broken down organelles autophagy 
entire cells autolysis 
any extracellular digestion
143
Q

What happens after lysosomes have finished digesting the contents?

A

Recycle stuff

144
Q

What is the structure of mitochondria?

A

Outer and inner mitochondrial membrane
double phospholipid bilayer
fluid filled interior cavity mitochondiral matrix

145
Q

Function of mitochondira?

A

ATP prod through cell resp

146
Q

Inner mitochondiral matrix contain

A

cristae (folds)

147
Q

What is ATP cycle

A

ADP + P arrows touch top bottom of ATP (and)

148
Q

What are the three types of cytoskeleton filaments

A

Intermediate filaments 8- 12 nm
Microtubles 25nm
Microfilaments 7nm

149
Q

structure of microfilaments

A

made from actin molecules assembles in Q long hains twited around each other

150
Q

microfilaments function

A

bear tension and weight promote motility if required

151
Q

microfilaments found

A

in all eukaryotic cells around periphery and lining at the interior of microvilli

152
Q

function of microfilaments

A

muscle contraction
cell division
cytoplasmic streaming

153
Q

How does microfilament do the function?

A

Anchoring cytoskeleton to plasma membrane proteins

154
Q

Is microfilaments permanent?

A

most permanent of cytosketon

155
Q

structure of microtubles

A

tubulin dimers twisted into coil to form a tube

156
Q

function of microtubules

A

support cell shape and size
scaffold or guide for movement of organelles
support cilia and flagella

157
Q

is microtubles permanent?

A

no

158
Q

function of microfilaments and intermediate filaments

A

bear tension and weigh in cell trough cell anchoring

159
Q

transcription occurs where?

A

in nucleus

160
Q

why is the template strand 3 to 5

A

because all proteins work and need to be manufactured in the 5 to 3

161
Q

what is the TATA sequence

A

5-TATAAAA - 3

162
Q

What doe RNA polymerase II bind to?

A

transcritpion factors and start codon

163
Q

intitation steps into 3

A

transcription factors bind to TATA box in promoter region of strands

RNA polymerase II binds to transcription factors and start codon of DNA

RNA polymerase II undertakes transcription moving 3 to 5 the template strand and the new mRNA is 5 to 3 opp

164
Q

Elongating include?

A

Elongating the growing mRNA strand

unwinding the DNA and rewinding after it has finsihed copying

165
Q

Hoe long does RNA polyermase II inwinnd DNA double helix?

A

10-20bpm at a time

166
Q

Where are the nucetides added as the mRNA gorws?

A

at the 3 end

167
Q

transcription rate in eukaryot?

A

40 nucelotide per sec

168
Q

elongationn step s

A

RNA polymerase II moves along DNA elongating the mRNA strand

mRNAstrand grows and comes out of DNA

DNA helix rewinds after it

169
Q

What happens in termination stage?

A

polyadenyoation signals is added after stop codon mRNA transcripts released

170
Q

How much does the polyadenylation signal is the mRNA trnascript?

A

10 - 35 downstrea

171
Q

sequence of adenylation signal

A

5-AAUAAA-3

172
Q

termination process steps

A

RNA poly reaches the stop codon
RNA poly transcribes a polyadenylation signal in the DNA
mRNA transcrpt is no 5-AAUAAA-3
10-35 downstrea, of the polyadenylation signal mRNA transcripts excised from the RNA poly

173
Q

Will only one codon code for an amino acid?

A

No! More than one codon will code for an amino acid

174
Q

What does that mean?

A

Each amino acid codon sequence will usually the same 2 bases and different 3 base

175
Q

Why?

A

Because there are only 20 amino acids where they differ are their side chains

176
Q

What are the three stop codons?

A

UUA
UAG
UGA

177
Q

What is the common thread?

A

Gene expression involves making proteins using a DNA template and RNA intermediary in order to fulfil a function need

178
Q

What does the sequence of DNA govern /

A

The sequence of mRNA which governs the sequence of the final protein

179
Q

What does the protein govern made from the DNA and mRNA?

A

The final shape and structure

As structure determines the function the DNA sequence is likely to determine the ability of the protein to function

180
Q

How does the sequence of the final protein link to the shape and structure?

A

Through the amino acid side chains and how they interact with each other

181
Q

What are amino acids

A

building blocks which make proteins

182
Q

When are amino acids reactive?

A

When they are in solution and are ionised

183
Q

How do proteins have different properties?

A

Size of protein
The content of amino acid
The sequence of amino acid

184
Q

How are amino acids numbered

A

N and C terminus

185
Q

What joins amino acids together?

A

A peptide bond (forms polypeptide)

186
Q

What are 3 features of a polypeptide?

A

Side chains stick out of the backbone
Directional N terminus and C terminus
It is flexible

187
Q

What is the classification for peptide

A

Less than 50 amino acids oligopeptide

188
Q

What is the classification of a polypeptide?

A

More than 50 amino acids

189
Q

How are proteins arranged?

A

Single polypeptides or multiple polypeptide bonded together

190
Q

How are theree different proteins?

A

Vary in shape according to function due to sequence of amino acids

191
Q

4 common types of proetins adn their shape?

A

TATA box binding protein: Butterfly shaped
Porin = doughnut shaped
Trypsin= globular
collagen= long fiber

192
Q

what do ribosomes contain?

A

both protein and ribosomal RNA (rRNA)

193
Q

What is the role of the large sub unit?

A

form peptide bonds

194
Q

Small subunit?

A

Hold mRNA in place

195
Q

What are the three site of tRNA are found in rbosomes?

A

A P E site

196
Q

A site?

A

Acceptor site for aminoacyl tRNA binds to mRNA codon

197
Q

P site?

A

peptide bond forms that adds an amino acid to the grwoing polypeptide chain

198
Q

E site

A

where tRNAs no longer bounded to an amino acid and exit the ribosome

199
Q

What is the ribsome described as?

A

A molecular machine that synthesises prteins

200
Q

Were are ribsomes assembled and what happens?

A

Assembled in the nucleolus and transported to the cytosol

201
Q

What is the 3 step sequence?

A

An aminoacyl tRNA carrying the correct anticodon for the mRNA codon enters the A sit

A polypeptide bond forms between the amino acid on the aminoacyl tRNA in the A site and the growing polypeptide chain on the tRNA in the p site

The ribosome makes ahead three bases and all 3 tRNAs move down one position and the tRNA in E site exits

202
Q

What is nascent polypeptide chain?

A

The chain that emerges from ribosome unstructured and non-functional chain

203
Q

What occurs when the nascent peptide chain leaves the ribosome?

A

It begins to fold into a 3D conformation due to polar non polar environment

204
Q

What is the definition of a polypeptide?

A

Unbranched polymers of the 20 amino acids held together by peptide bonds

205
Q

What is a protein?

A

3D structured functional chain

Unbranced polymers of 20 amino acids held by peptide bonds with a specific 3D shape or function

206
Q

What are the building blocls of protein?

A

Amino acids linked though a peptide bond

207
Q

What are the 4 types structures of polypeptide?

A

Primary
Secondary
Tertiary
Quartenary

208
Q

What is primary structure?

A

linear order of the amino acids determined by order of codons of mRNA

209
Q

Secondarystructure?

A

By maximising the hydrogen bonding between parts of the polypeptide backbone (segments of polypeptide chain)

210
Q

When does polypeptied bcome a protein?

A

Tertiary, 3D

211
Q

What are the 2 subtypes of secondary structure?

A

Alpha helix

Beta sheet

212
Q

How is alpha formed?

A

The primary chains is coiled to form spiral structure which is stabilised by H bonds

213
Q

Beta sheet fomed?

A

The primary chain zig zags back and forth forming a pleated sheet. Adjacent strands are held together by H bonds

214
Q

What is the transition from 1 to 2 structure?

A

O from C=O form H bond with H from N-H

215
Q

How do 3 structures arise?

A

From interaction between amino acids side chains groups

216
Q

WHat interactions for 3 to arise?

A

H bonds between polar side chains
Hydrophobic interaction collapse(tdd between non polar side chains)
Ionic bonds between charged amino acids side chains
disulphide bridges between cystine molecules

217
Q

What is the strongest interactiona nd why

A

Disulphide bridges as it is covalently bonded (reinforce shape)

218
Q

WHy is here hydrophobic interactions

A

Hydrophobic groups will pack closely together at the core of the protein to get away from water and cytosol

219
Q

What is 3 structure?

A

Superimposed on 2 structure alpha helix and/or beta sheet are folded up to form compact globular molecule held together by intramolecular bonds

220
Q

Example of 3 structured proetin?

A

Prealbumin (transthrytin) transports the thyroid hormone throxine in serum and cerospinal fluid (CSF)

221
Q

What is 4 structure

A

2+ oligomerise polypeptide chains each with their own 3 structure aggregated to form a larger macromolecular complex (to achive full functionality)

222
Q

example of 4 strcutre and how it oligomerises

A

2 identical prealbumin subunits join together head to tail to form dimer

223
Q

What determines how a protein will function?

A

The intricate structure or the complex as it has a specific shape

BIOSCI 107 (8 decks)

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