module 1: what is life Flashcards
(112 cards)
1
Q
where do cells come from
A
pre existing cells
2
Q
what does the structure of a cell or protein mean
A
the structure determines the function
3
Q
can cells communicate with each other
A
yes they can
4
Q
are virus alive
A
no
5
Q
why are viruses not alive
A
because they are no comprised of cells, they cannot extract energy, cannot replicate
6
Q
what are the 2 theory’s of the forces of life
A
1) life formed spontaneously
2) extra terrestrial life
7
Q
what is a proto-cell
A
a lipid based semipermeable structure that allows some things in and some things out
- happens when lipids are put into water due to its hydroscopy properties
8
Q
what are the 4 biomacromolecules
A
-proteins
-lipids
-carbohydrates
-nucleic acids
9
Q
what are lipids comprised of
A
C, H and O
10
Q
do lipids contains lots of oxygen
A
no, this means they are insoluble in water
11
Q
why are lipids insoluable in water
A
because they are comprised of long hydrocarbon chains (non polar)
12
Q
can lipids store energy
A
yes they can
13
Q
what is a lipid made up from (structure)
A
phosphate head- which is hydrophilic water loving
fatty acid tail- hydrophobic (water hating)
14
Q
what is a condensation reaction
A
building up a molecule, water is released
15
Q
what is a hydrolysis reaction
A
breaking down of a molecule, water is needed
16
Q
what are the 2 types of fatty acids
A
1) unsaturated
2) saturated
17
Q
what is a saturated fatty acid
A
a fatty acid that only contains carbon carbon single bonds. this increases dispersion forces and allows these fatty acids to be solid at room temp
- more energy is required to break these bonds
18
Q
what is an unsaturated fatty acid
A
a fatty acid that contains one carbon carbon double bond, these molecules are typically liquids at room temp because they contain a kink in the chain that decreased dispersion forces, thus less energy is needed to break the bonds
19
Q
what are the 3 elements that a carbohydrate is made up of
A
C, H, O
20
Q
what are carbohydrates used for
A
-source of energy
- structure (cellulose in plants)
21
Q
what is the formular of a carbohydrate
A
(CH2)n
22
Q
what is a monosaccharide
A
a single sugar molecule
23
Q
what is a disaccharide
A
2 sugar molecules joined together
24
Q
where is the hydroxyl group located on an alpha sugar
A
down the bottom
25
where is the hydroxyl group located on a beta sugar
up the top
26
what is a glycosidic link
the bond that joins 2 sugars together
-this bond is a ---O--- bond
- this process is known as condensation
27
what happens when glucose and glucose is bonded together
results in maltose (alpha 1-4)
28
what happens when galactose is bonded to glucose
results in lactose (beta 1-4)
29
what happens when glucose is bonded to fructose
results in sucrose (alpha 1-4)
30
what is cellulose
a long chain molecule that has little branching which creates a really strong cell wall
- a molecule in the cell wall of plants
31
is starch
- a molecule that used to store energy in plants
32
is starch branched
yes it is branched but only to a small degree
33
where does the branching occur in starch
at C1 and C6
34
what is glycogen
a molecule that stores energy in humans
35
is glycogen branched
yes
36
what are the bases in DNA
A, T, C and G
37
what are the bases in RNA
A, U, C and G
38
what are the pyrimidines
C, U, T
- only contain one hexagon
39
what is a purine
A and G
- contain 2 hexagons joined together
40
what direction does DNA run in
runs in a 5' to 3' direction
41
what bond joins 2 nucleotides together
a weak hydrogen bond
42
what is a monomer of a protein
amino acid
43
what does an animo acid consist of
- central carbon, hydrogen, R group, a carbonyl group and an amine group
44
what are some of the functions of proteins
- enzymes
- defense
- storage
- transport
- structure
45
what is a peptide bond
a bond that joins 2 amino acids together
-CONH
46
what is the n terminus
the end where the amine group is
47
what is the c terminus
the end where the carbonyl group is
48
what enzyme joins 2 amino acids together
peptidyl transferase
49
what is the primary structure of a protein
the sequence of amino acids
50
what is the secondary structure of a protein
the coiling and folding of the protein chain resulting in alpha helices and beta pleated sheets
51
what is the tertiary structure of a proteins
the 3D nature of a protein which is determined by the bonding and interrogations of the R group
52
what is the quartnary structure of a protein
where there are 2 or more polypeptides joined together
53
what bonds can be found in the tertiary structure
-hydrogen bonds
- ionic bonds
- hydrophillic bonds
-hydrophobic bonds
-van der waal interactions
- disulphide bridges
54
what bonds can be found in the tertiary structure
-hydrogen bonds
- ionic bonds
- hydrophillic bonds
-hydrophobic bonds
-van der waal interactions
- disulphide bridges
55
what is the smallest unit of life
cells
56
what are 2 types of prokaryotic cells
- bacteria
- archaea
57
what are prokaryotic cells comprised of
- circular DNA
- ribosomes
- generally smaller
58
what do prokaryotic cells lack
- no membrane bound organelles
- no nucleus
59
why are cyanbacteria important
becuase they were responsible for the oxygenation of the earth and were the first species to undergo photosynthesis
60
what is binary fission
the way of reproduction for prokaryotic cells
61
what are the steps of binary fission
1. circular DNA is attached to the plasma membrane at a specific point
2. DNA is replicated
3. the new DNA is attached to a different point at the plasma membrane and the membrane will grow inwards
4. this creates a new cell via cytokinesis
62
what qualifies a eukaryotic cells
- nucleus
- membrane bound organelles
- generally much larger
63
what surrounds the nucleus
the nuclear envelope
64
what is the purpose of the pores in the nucleus
- to allow genetic infomation out of the cell
- for example pre mRNA
65
what are chromosomes
a molecule that contains the genetic information of a cell
66
what are chromosomes made up of
made up of chromatin
67
what happens at the mitocondria
production of ATP
68
how many organelles does the mitochondria have
2
69
how occurs at the chloroplasts
photosynthesis
70
how many organelles does a chloroplast have
2
71
how many organelles does a chloroplast have
2
72
what is the origin of the mitochondria
- arose from purple bacteria
- formed a relationship with an aerobic bacteria
73
what is the evidence for endosymbiosis
- organelles are morphological similar
- they are double membrane bound
- they contain their own ribosomes
74
what is the endoplasmic reticulm made up of
cristernae
75
explain the SA:V of the ER
has a high SA:V ratio due to the folding
76
what are the two types of ER
- smooth ER
-rough ER
77
what occurs at the ER
site of synthesis of proteins, glycoproteins, carbohydrates and lipids.
78
what does the smooth ER synthesise
the smooth ER secretes carbohydrates and lipids
79
what is the function of the golgi body
responsible for the collection and packaging of molecules
80
what are lysosomes
they break down material ingested by endocytosis or recycle old organelles
81
what is it called when a lysosomes recycles an old organelle
autophagy
82
what do vacuoles do
preform a wide range of functions like storage of nutrients and maintain the cell structure
83
what are mircobodies
an organelles that contains enzymes to catalyse the breakdown of hydrogen peroxide (h2o2)
84
what are the 2 types of microbodies
-peroxisomes
and
-glyoxysomes
85
what do peroxisomes break down
amino acids
86
what do glyoxysomes break down
fatty acids
87
what occurs in the cytosol
a bunch of biochemical reactions
88
what is the role for the plasma membrane
to prevent the flow of lipids in and out of the cell due ti the hydrophobic middle region and protect the cells interior
89
is the plasma membrane a liquid
YES IT IS MOVING ALL THE TIME
90
does simple diffusion require energy
no
91
what is simple diffusion
the diffusion of a substrance from an area of high concentration to an area of low concentration
- along the concentration gradient
92
what is osmosis
the diffusion of water from an area of high solute concentration to an area of low solute concentration
93
what is a hypotonic solution
when the concentration of solution is lower than the concentration of the cell and thus water comes into the cell
94
what is a hypertonic solution
whe the concentration of solution is higher then the concentration of the cells and this water moves out of the cell and into the solution
95
what is an isotonic solution
both concentrations are the same and thus there is a net zero movement
96
what is faciliated diffusion
the use of transport proteins to move larger molecules into and out of the cell down the concentration gradient
97
what must happen for cell division to be success
the genetic material must be replicated accurately and distributed into the 2 daughter cells
98
what are the steps cell division in eukaryotic cells
interphase and mitosis
99
what are the 3 stages of interphase in order
1) G1
2) S
3) G2
100
what happens in G1
- organelles are made
- synthesis of proteins and enzymes
- growth
101
what happens at the s phase
- growth
- metabolic activity
- DNA replication
102
what happens in the G2 phase
-preparation for cell division
- growth
-metabolic activity
103
what stage does DNA replication take place
the s phase
104
what are the stages of DNA replication
- DNA helicase unwinds the DNA by disrupting the hydrogen bonds between the nitrogenous bases
- DNA polymease goes along the leading strand and creates a complimentary leading strand
105
what are the stages of mitosis in order
-prophase
-metaphase
-anaphase
-telephase
106
what happens in prophase
- chromosomes condense
- spindle fibres begin to form
107
what happens in metaphase
- nuclear membrane break apart
-spindle fibres attach to the chromosomes
-chromosomes line up to the equator of the cell
108
what happens in anaphase
-spindle fibres shorten (pulling the chromosome to one end of the cell
- centromere divides
- the production of 2 chromatids
109
what happens in telophase
- the nuclear membrane forms around each set of chromosomes
110
what
111
where are the checkpoints during cell division
-G1
-G2
- metaphase
112
what is the checkpoint at G1
cyclin CDKs prevent the progression of the cell cycle is ssDNA is found. this process activates the production of and ATR protein which halts the S phase
