Bio Notes Midterm Flashcards
1
Q
Acronym for properties of life
A
ospmrarg
2
Q
Properties of life: O
A
cells exhibit ordermade of parts/organelles with specific functions
3
Q
Properties of life: S
A
Cells are assembled from same kind of atoms/molecules/macromolecules
4
Q
Properties of life: P
A
cells process energy and obey the same laws of energy
5
Q
What is the 1st law of thermodynamics?
A
Conservation of energy, energy cannot be created or destroyed; it can only be converted from one form to another (transformation)
6
Q
What is the 2nd law of thermodynamics?
A
cells require continual energy input from food (cellular respiration) or form sunlight (photosynthesis)
7
Q
What do these 2 laws of energy help explain? (2)
A
- Energy flows but do not cycle2. Sunlight —> chemical energy —> kinetic energy (transformation of one form of energy to another)
8
Q
Properties of life: M (also R)
A
cells metabolize (perform chemical activities) and they need to regulatethese activities to maintain homeostasis.
9
Q
What does metabolize mean?
A
perform chemical activities
10
Q
What does homeostasis mean?
A
Balanced internal environment
11
Q
Properties of life: R (first one)
A
Cells can respond to specific conditions in the environment
12
Q
How do cells respond to conditions of their environment?
A
they change their metabolism, pattern of behavior
13
Q
How fast do cells respond to specific conditions of their environment?
A
Immediate
14
Q
Properties of life: A
A
cells are adapted to their environment
15
Q
How do cells adapt to their environment?
A
evolutionary adaption
16
Q
How fast do cells adapt to their environment?
A
They evolve (it takes time and maybe even centuries)
17
Q
What property of life is described? A stick insect resembles the twig (stick) it sits on? [Image]
A
Evolutionary adaptation
18
Q
What property of life best matches the following statement?Cells extract energy from glucose to synthesize ATP, a form of chemical energy in the cell
A
Energy transfer
19
Q
Properties of life: R (2nd)
A
Cells can reproduce
20
Q
What does reproduction of the cell imply?
A
Pass on traits to offspring through heritable instructions in DNA.
21
Q
Properties of life: G
A
Growth and development
22
Q
A caterpillar transforms into a butterfly over time. Which property of life does this demonstrate?
A
Growth and development – The caterpillar undergoes metamorphosis, a developmental process that changes its structure and function.
23
Q
A human sweats when it is hot to cool down. Which property of life does this demonstrate?
A
Regulation – Sweating helps regulate body temperature and maintain homeostasis.
24
Q
A Venus flytrap closes when a fly lands on it. Which property of life does this demonstrate? [Image]
A
Response to the environment – The plant reacts immediately to the stimulus of touch by closing its trap.
25
A bacterium divides into two identical cells. Which property of life does this demonstrate?
Reproduction – The bacterium undergoes asexual reproduction by binary fission to create new organisms.
26
A population of rabbits in snowy environments develops white fur over generations to avoid predators. Which property of life does this demonstrate?
Evolutionary Adaptation – This describes a genetic change in a population over time to improve survival.
27
What is the hierarchy levels of biological organization? (9)
1. Atoms2. Molecules (H2O)3. Macromolecules4. Organelles5. Cells6. Tissues7. Organs8. Organ system (heart - cardiovascular)9. Organism
28
What are examples of organelles?
nucleus, mitochondria, etc
29
What are the macromolecules that all organisms are made of? (4)
- Carbohydrates (sugars)- Lipids (oils, fats)- Proteins (hemoglobin)- Nucleic Acid (DNA, RNA)
30
What is the basis of biogenesis?
cells are only made of pre-existing cells
31
What are the purposes of cellular division? (2)
1. Reproduction 2. Growth and Repair
32
What are the 2 types of cells?
Prokaryotes and Eukaryotes
33
Give me 2 examples of prokaryotic cells
BacteriaArchaebacteria
34
What are the characteristics of prokaryotic cells? (3)
- small - 1 micrometer (10^-6)- no nucleus
35
Give me examples of eukaryotic cells: (4)
- fungi- plants- protists- animals
36
What are the characteristics of eukaryotic cells? (3)
- larger- 100 micrometer- have other organelles (membrane bound)
37
Identify each type of cells: [Image]
Bigger: eukaryotic smaller: prokaryotic
38
What are the 3 domains?
- bacteria- archae- eukarya
39
Why are viruses considered non-living?
Because they can’t replicate/reproduce w/o a host cell
40
What are the characteristics of viruses? (2)
- small: 10-20 nanometers (10^-9m)- have SOME properties of life
41
Are viruses considered dead cells?
NO, because they retain some properties of life
42
What are the properties of life that viruses have? (4)
- consists of genetic information (DNA/RNA)- contained within a protein shell: capsid- have specialized enzymes - proteins that allow host specific infection and replication- some capsid have additional membranous envelope from the host cell
43
What role does nucleic acid play in viruses?
Contains information for replicating viral particles, including the capsid and other viral proteins.
44
What is the protein shell that viruses are contained within called?
Capsid
45
What do specialized enzymes - proteins allow in viruses?
host specific infection and replication
46
Viruses replicate or divide?
Replicate
47
Are macromolecules the same as cells?
No, macromolecules are in cells
48
What do organic compounds consist of?
H hydrogen covalently bounded to C carbon atoms
49
What do organic compounds form?
Linear and ring-shaped backbones
50
What are the other common elements in organic compounds?
CHNOPSN - nitrogenO - oxygenP - phosphorusS - sulfur
51
What are O, N, P, S linked to?
Carbon backbone of cellular organic compounds
52
What is CO2 considered as?
inorganic (not an organic carbon compound)
53
What do functional groups attached to the carbon backbone pass on?
Diverse properties to organic compounds that are the characteristics of life
54
What can only living cells assemble?
Large organic compounds called macromolecules and polymers
55
What are polymers?
large molecules made of monomers
56
List the 4 carbon compound groups (contain carbon as fundamental element):
4 macromolecules1. Complex carbohydrates 2. Lipids3. Proteins4. Nucleic acids
57
What is metabolism?
Chemical reactions that occur in the cell
58
Describe metabolism
Transformation of substances into energy or materials
59
What are the 2 types of metabolism?
AnabolismCatabolism
60
What is anabolism?
A synthesis (building) rxn
61
Describe the process of anabolism
Linkage of monomers to form polymers by dehydration synthesis, and water is produced/released
62
Which process is this? [Image]
Anabolism
63
True or False: Anabolism requires input of energy
True, because building requires energy
64
True or False: Catabolism requires input of energy
False, because breaking “releases energy”
65
What is catabolism?
breakdown rxn
66
Describe catabolism:
Macromolecules are broken down/digested to their respective monomers by hydrolysis, water is used as a reactant/added
67
What are organic compounds?
Compounds that contain carbon and are found in living organisms.
68
Which process of metabolism is this? [Image]
Catabolism
69
Give me an example of catabolic rxn
Digestion - hydrolysis of food and hydrolysis of macromolecules by lysosome in white blood cells
70
Does cellular respiration involve hydrolysis reactions?
No, it is an overall catabolic process but doesn’t involve hydrolysis
71
Flow chart of the hydrolysis of macromolecules in diet
[Image]
72
What is the most abundant macromolecule?
Carbohbydrates
73
What is the general composition of carbohydrates?
CHO (N in chitin)
74
What are the types of carbohydrates? (3)
- monosaccharides (sugars)- disaccharides- polyssaccharides
75
What is the composition of monosaccharides (sugars)?
(CH2O)n- n for number of carbon (C)
76
What are the monomers of carbohydrates?
monosaccharides
77
Give me examples of monosaccharides (4)
- glucose- fructose- glucosamine- galactose
78
How many carbons does glucose have?
6
79
What is the linear and ring form of glucose?
[Image] [Image]
80
Are disaccharides considered polymer?
NO
81
What are disaccharides made of?
2 sugars (monosaccharides)
82
Function of disaccharides
Store energy
83
Examples of disaccharides: (3)
- maltose (beer)- sucrose (table sugar)- lactose (milk)
84
Synthesis of maltose
bonding of two glucose - carbon 1 and carbon 4 links [Image]
85
Synthesis of sucrose
Glucose + fructose (fructose 5 sided ring) [Image]
86
Which type of carbohydrate is considered the only true polymer?
Complex carbohydrates or polysaccharides
87
How are polysaccharides made?
dehydration synthesis of multiple monomers
88
What are the functions of polysaccharides? (2)
- storage of energy- structural role in the cell
89
What type of glucose is used for energy and chemical storage?
alpha-glucose
90
What are the polysaccharides used for energy storage? (2)
- glycogen (animals, stored in liver cells)- starch (plants, stores in chloroplasts)
91
What type of glucose is used for structural support?
beta-glucose
92
What polysaccharides provides structural support in plant cell walls?
Cellulose
93
What structural carbohydrate is found in the cell walls of fungi?
Chitin (CHON)
94
What is chitin?
chain of glucosamine
95
What is the main monomer of polysaccharides?
Glucose
96
What is the structure of alpha-glucose?
H on top in the first carbon [Image]
97
What is the structure of beta-glucose?
H on the boots on the first carbon [Image]
98
What type of glucose are starch and glycogen (storage) made of? What is the structure of starch?
- alpha-glucose- OH on the aligned on the bottom [Image]
99
What type of glucose are cellulose made of? What is the structure of cellulose?
- beta-glucose- alternating OH positions [Image]
100
Which group of macromolecule isn’t a true polymer? Why?
Lipids, but due to their size they are considered macromolecules. They don’t have a single repeating monomer, that have more than one type of subunit!
101
What is the characteristic of lipids?
Heterogeneous, hydrophobic (water fearing, insoluble in water)
102
What is the general composition of lipids?
CHO (N and P in phospholipids)
103
What are the monomers of lipids?
FAG: Fatty Acids linked to Glycerol (For fats, oils, phospholipids)
104
What are the two main functions of lipids?
1. Energy storage 2. Structural
105
What are the two main functions of lipids?
1. Energy storage2. Structural
106
What are the two main functions of lipids?
1. Energy storage2. Structural
107
What is the main lipid used for energy storage?
Triacylglycerides (triglycerides) ➡️ fat made of 3 fatty acids and one glycerol
108
What are the two types of energy-storing lipids, and where are they found?
• Fats – Found in animals, used for insulation and protection.• Oils – Found in plants.
109
What type of lipid is the main structural component of cell membranes?
Phospholipds
110
What is a characteristic of phospholipids?
They are amphipatic
111
Why are phospholipids amphipatic?
They have two parts:• Hydrophilic (water-loving) heads• Hydrophobic (water-fearing) tails
112
Which type of lipid consists of four fused carbon rings?
Steroid
113
What are the types of steroid lipids? (2)
- cholesterol- steroid hormones
114
What is the function of cholesterol in the body? (3)
• Structural component of cell membranes• Precursor for steroid hormones (base for forming)• Component of bile salts (aiding in fat digestion) [Image]
115
What is the function of steroid hormones?
Regulate metabolism and reproduction, etc
116
What lipid-based molecules act as cofactors required for absorbing light?
Retinal and carotenoids
117
What does this represent? [Image]
Fat molecule (triglyceride) by dehydration synthesis that combines 1 glycerol and 3 fatty acids w/ Easter linkages (covalent bond that forms between a hydroxyl (-OH) group and a carboxyl (-COOH) group)
118
Identify saturated and unsaturated fat: [Image]
Left: saturatedRight: unsaturated
119
What is the main structural difference between saturated and unsaturated fatty acids?
• Saturated: No C=C (double) bonds.• Unsaturated: 1 or more C=C (double) bonds.
120
What is the shape of saturated vs. unsaturated fatty acids?
• Saturated: Linear.• Unsaturated: Bent/Kinked due to double bonds.
121
How do saturated and unsaturated fatty acids behave at room temperature?
• Saturated: Solid at room temperature.• Unsaturated: Liquid at room temperature.
122
What are the typical sources of saturated vs. unsaturated fatty acids?
• Saturated: animal fats & butter (mostly).• Unsaturated: vegetable oils.
123
What are the main components of phospholipids?
1. Hydrophilic head (contains phosphate group).2. Hydrophobic tails (fatty acid chains).3. Glycerol backbone (Holds everything tgt)
124
Where are phospholipids found in?
cell membrane in all cells
125
What structure do phospholipids form in cell membrane?
Bilayer - 2 rows parallel to each other with hydrophilic head facing water and hydrophobic tail meeting inside
126
Is there water inside the cell membrane?
No, the hydrophobic tails creates a barrier between the inside and outside of the cell
127
What is a micelle?
circular structure made of phospholipids hydrophilic head outward and hydrophobic tails inward
128
What is the difference between the cell membrane and the cell wall?
• Cell membrane: all cells (phospholipid bilayer)• Cell wall: in plants & fungi (structural support)
129
Is cholesterol considered a hormone?
No, its an exception from all steroids
130
What are the most diverse macromolecules (w/ diverse functions)?
Proteins - polypeptides
131
Composition of proteins
CHNOS (only ones with sulfur!)
132
Monomers of proteins - polypeptides
20 different amino acids (aa)
133
What does each aa have?
A side chain that gives it unique properties and affects the protein’s function [Image]
134
Synonym of side chains
R group
135
What are the bonds between aa called?
peptide bond
136
What are peptide bonds?
N-C bond (protein)
137
Carboxyl and amino group components
Carboxyl: COOHAmino: NH2Picture of amino acid [Image]
138
What is infinite?
number of different proteins
139
What does the number of proteins depend on? (3)
N: number of aaC: composition of aaS: sequence of aa
140
SPF?
different sequence ➡️ different proteins ➡️ different functions
141
How is the shape of a protein obtained?
folding of aa sequence into secondary, tertiary and quaternary structures
142
Which structure of aa sequence is this? [Image]
Primary structure
143
What’s the orientation of proteins?
N ➡️ C
144
Which aa sequence structure is this? [Image]
Secondary
145
Which structure of aa sequence is this? [Image]
Tertiary - some proteins may contain only alpha helices, only beta sheets, or a mix of both.
146
Which structure of aa sequence does this represent? [Image]
Quaternary - 2 or more polypeptides (proteins)
147
Are the 4 structures a cycle?
NO! Each level builds on the previous one but does not loop back.• Primary → Secondary → Tertiary → Quaternary (if applicable).• Once a protein reaches its functional form, it usually stays that way unless it is denatured (unfolded due to heat, pH, or chemicals).
148
At which structure is the protein considered functional?
At the tertiary (if single polypeptide, e.g. myoglobin) or quaternary (multiple polypeptides, e.g. hemoglobin)- at these structure the protein is finished in 3D form!
149
Primary structure: (2)
- aa sequence form N (amino) to C (Carboxyl) terminus- peptide bonds
150
Secondary structures: (2)
- alpha-helices and beta-strands- held tgt by H-bonds between CO (Carboxyl) and NH (amino) of backbone [Image]
151
Tertiary structure: (2)
- 3D shape- held by interactions between R groups of aa (including S-S bonds)
152
What are SS bonds? Which structures?
- Strong Shape bonds- tertiary and quaternary structure
153
Do hydrogen bonds form between alpha helices and beta sheets?
No! H-bonds form within alpha helices and between beta strands, not between the two structures.
154
Quaternary structure: (2)
- complex of 2 or + polypeptides- also held by interactions between R groups of aa
155
List the 8 functions of protein:
ESSTHRCDE: EnzymesS: StructuralS: StorageT: TransportH: HormonesR: ReceptorsC: Contractile and motileD: Defensive
156
What do functions of proteins depend on?
on the shape and shape ➡️ aa sequence
157
What do names of enzymes end with?
ase
158
What do enzymes do?
Increases the rate of rxn
159
Give me example of enzymes (2)
- cellulase (break down the cellulose molecule) in green- lipase (break down fat in your diet) in rainbow [Image] [Image]
160
What do enzymes with structural function do?
strengthen and support tissues and cells
161
Give me examples of structural enzymes (2)
- collagen (building of joint cartilage)- keratin (helps form hair, nails and your skin's outer layer) [Image] [Image]
162
What do storage enzyme do?
nourish embryo [Image]
163
Give me an example of storage enzyme:
ovalbumin (protein of egg white - liquid)
164
What do transport enzymes do? (2)
- transport gases and minerals in blood- transport across membranes of cells
165
Give me the name of the enzyme that transports gases and minerals in blood
hemoglobin (red blood cells) [Image]
166
Give me the names of the enzymes that transport molecules across cell membranes (3)
- Pumps- Channels- Transporters
167
What do hormonal enzymes do?
maintain homeostasis
168
Name a hormonal enzymes:
insulin
169
What do receptor enzymes do?
Sense and transduce (to pass a message inside the cell) environmental signals
170
Name a receptor enzymes:
SynapseTrick! Sense ➡️ synapse
171
What do contractile and motile enzymes do?
muscle contraction and cell movement
172
name contractile and motile enzymes (2):
Actin and myosin(TRICK: Action and movement)
173
What do defensive enzymes do?
fight diseases and foreign molecules
174
Give me example of defensive enzymes:
Antibodies - immunoglobulins (immuno ➡️ Immune system)
175
Which macromolecule contains information?
Nucleic acids
176
Composition of nucleic acids:
CHNOPS
177
What are the monomers of nucleic acids?
nucleotides
178
What are the bond between nucleotides called?
phosphodiester
179
What are the two forms of nucleic acids?
- DNA- RNA
180
DNA = ?
deoxyribonucleic acids
181
What are DNA made of?
4 different deoxyribonulceotides ➡️ Monomer of DNA
182
Function of DNA?
Storage of genetic information
183
RNA = ?
ribonucleic acids
184
What are RNA made of?
4 different ribonucleotides ➡️ Monomer of RNA
185
What is the function of RNA?
protein synthesis (making, creating proteins)
186
Give me an example of a nucleotide that has a central role in metabolism as energy carriers
ATP ➡️ adenosine triphosphate
187
Difference in overall structure of DNA and RNA:
DNA: ds (double stranded) ➡️ Double helix, antiparallel, complementaryRNA: SS (single stranded) [Image]
188
Difference in monomers DNA and RNA:
DNA: deoxyribonucleotidesRNA: ribonucleotides
189
Difference of pentose sugar DNA and RNA:
DNA: deoxyribose (OH and H)RNA: ribose (x2 OH) [Image]
190
Difference of the base between DNA and RNA:
DNA: GATCRNA: GAUC
191
Difference in functions for DNA and RNA:
DNA: store genetic informationRNA: genetic info for making proteins in cytoplasm
192
Where are DNA and RNA found in the cell?
✔ DNA: Nucleus✔ RNA: Cytoplasm
193
What is chromatin?
✔ DNA packaged with proteins✔ Forms chromosomes [Image] [Image]
194
Name the base for DNA ➡️ GATC
G ➡️ GuanineA ➡️ AdenineT ➡️ ThymineC ➡️ Cytosine
195
Name the bases for RNA ➡️ GAUC
SAME AS DNA instead U replaces TU ➡️ Uracil
196
What is the direction of a DNA strand?
5’ → 3’
197
What do we find on carbon 5’ and 3’?
- Phosphate on 5’ carbon- Sugar + OH on 3’ carbon
198
What is the bas pair rule for DNA?
A - TC - G
199
Why are the two strands of DNA considered antiparallel?
becaus their orientation is opposite5’ ➡️ 3’3’ ➡️ 5’
200
What are double helix?
form of DNA [Image]
201
How many combinations of aa are possible in a polypeptide (protein)?
20^nn = # of aa in protein
202
What does this represent? [Image]
ATP
203
What are the three components of ATP
- adenine- ribose- 3 phosphates [Image]
204
What is the role of ATP?
energy currency of cell ➡️ It gives cells the power to do work
205
What is the hierarchy of DNA/RNA structure?
1. Polynucleotide/Nucleic Acid ➡️ long chain of nucleotides linked tgt2. Nucleotides ➡️ Pentose sugar + Nitrogeneous bases + Phosphate group3. Nitrogenous bases and sugars ➡️ GATC/GAUC and Deoxyribose/Ribose [Image] [Image] [Image]
206
What are the three components of nucleotides?
- phosphate group- nitrogenous base- sugar [Image]
207
What is the name of this reaction? [Image]
Hydrolysis of ATP
208
Explain the hydrolysis of ATP: (3)
- ATP + water ➡️ ADP + P (inorganic phosphate) + release of Gibbs free energy- It’s inorganic because its not attached to a carbon-based molecule- ADP ➡️ because there’s not 3 phosphate but only two attached to the ribose and adenine ➡️ diphosphate
209
What is ATP hydrolysis associated with?
release of Gibbs free energy
210
What types of cellular work does ATP power, require energy? (3)
1. Chemical work → Powers anabolic reactions (building molecules)2. Mechanical work → cellular mvt, muscle contraction3. Transport → molecules across CM
211
Describe ATP cylce
1️⃣ ATP is broken down through hydrolysis with water → Releases energy for the cell (for 3 types of cellular work)2️⃣ ADP & Pi are recycled → Energy from food recharges ATP.3️⃣ The cycle repeats so the cell always has energy [Image]
212
Name for releasing and input of Gibbs free energy
Exergonic ➡️ release G energyEndergonic ➡️ input of G energy
213
What is the backbone of proteins?
[Image]
214
What is the basis of biogenesis?
all cells are made of pre-existing cells
215
Size range of cells?
1-100 micrometer
216
What are the two main types of microscopes used to observe cells?
- Light: visible light optics (lenses), live specimens w/ limited resolution and magnification, colored image- Electronic: electron optics (magnets), fixed specimens (dead), better resolution and magnification, b&w [Image]
217
3 characteristics of the plasma membrane (PM):
✔️ 9nm, phospholipid bilayer + proteins (animal) / + cholesterol (plant)✔️ Semi permeable or selectively permeable✔️ Transport proteins to let hydrophilic molecules pass
218
Prokaryotes DON’T have _____________
Membrane bound cytoplasmic organelles:❌ Nucleus❌ Mitochondria❌ GolgiEtc.
219
List the 7 parts of a prokaryotic cell - bacteria and their function:
1. Nucleoid (contains DNA - single circular chromosome)2. Ribosomes (protein synthesis)3. Plasma membrane4. Flagella (locomotion - allow motion)5. Cell wall (peptidoglycan)6. Capsule (sticky polysaccharide) with ⬇️7. Pili (attachment) [Image]
220
Which type of eukaryotic cell(s) is mitochondria present - cellular respiration?
✅ plant✅ animal
221
Which type of eukaryotic cell(s) is chloroplast present - photosynthesis?
✅ plant❌ animal
222
Which type of eukaryotic cell(s) is cell wall present?
✅ plant❌ animal
223
Which eukaryotic cell(s) have centrosome?
Plant and Animal
224
Which eukaryotic cell(s) have centrioles?
ONLY animal cells
225
What is the centrosome called in plant cells?
MTOC
226
Which organelles does the storage and treatment of waste in plant and animal cells?
Plant: vacuole (H2O regulation - homeostasis)Animal: lysosome
227
Which eukaryotic cell has flagella and cilia?
animal cells
228
What does the cell wall prevent the plant cell from doing/having?
- phagocytosis- flagella- cilia
229
List all the organelles present in eukaryotic cells (precise if only in animal or plant) ➡️ 11
Nucleus:1. Nucleus2. Nucleolus3. Nuclear envelope Endomembrane system:4. RER5. SER6. Golgi7. Lysosome (animal)8. Vacuole (plants)Organelles w/ role in metabolism:9. Mitochondria10. Chloroplasts11. Peroxisome
230
Describe the functions of all 3 organelles that make the nucleus:
1. Nucleus:➡️ holds DNA information➡️ site for DNA replication➡️ chromatin2. Nucleolus (in the nucleus kind of like the lava inside the earth):➡️ rRNA synthesis (r for ribosomal)➡️ forms ribosome3. Nuclear envelope:➡️ double membrane (2 phospholipid bilayer)➡️ Has pores that allows passage of molecule from the cytoplasm [Image]
231
What is the role of the endomembrane system?
produce, fold, modify, sort and transport proteins
232
Function of RER (2)
1. Has ribosomes ➡️ That’s why its called ROUGH ER2. Protein synthesis
233
Function of SER: (4)
1. no ribosomes ➡️ SMOOTH2. Lipid synthesis: phospholipids, steroid, cholesterol3. Detoxification4. Stores Ca2+ ➡️ Muscle fibres
234
Function of Golgi (2)
1. Protein folding and modification2. Sorting and shipping
235
Where does lysosome originate from?
Golgi!
236
What are lysosomes and what do they contain inside?
Vesicle that transport hydrolytic enzymes for digestion of macromolecules
237
What are the two processes where lysosomes are involved in?
1. Phagocytosis ➡️ Digestion of large food molecules2. Autophagy
238
What is autophagy?
“eat own self” ➡️ Lysosome fuses with an old organelles or proteins to break them down and recycle them
239
What is the “equivalent” of lysosome for plant cells?
Vacuole
240
Function of vacuoles (2)
1. Storage of wastes2. H2O homeostasis
241
Flow chart of endomembrane system
[Image]
242
Explain each step of the endomembrane system (5)
- DNA : Template for making RNA (proteins)- mRNA : goes from nucleus to the cytoplasm carrying the genetic code to …➡️ cytoplasm filled (synthesis of proteins w/ ribosomes)➡️ RER (synthesis of proteins w/ ribosomes)- RER➡️ SER (lipid synthesis)➡️ Sends proteins to Golgi- Golgi: packages proteins from transport➡️ Lysosome/Vacuole (hydrolytic enzymes)➡️ Secretory vesicles- Secretory vesicles➡️ PM (secretory proteins, out of cell)➡️ PM (membrane proteins)
243
What are the two organelles that have a role in metabolism and state which cell they are located in:
- Mitochondria ➡️ all eukaryotic cells- Chloroplasts ➡️ Plant cells
244
Function of mitochondria? (2)
1. ATP synthesis2. Cellular metabolism
245
Function of chloroplasts
Photosynthesis
246
What do both chloroplast and mitochondria have in common? (3)
- double membrane- ribosomes- DNA
247
What is the endosymbiont theory?
Chloroplasts and Mitochondria originate from bacteria
248
What did mitochondria originate from?
ancestral aerobic bacteria
249
What did chloroplasts originate from?
ancestral photosynthesis bacteria
250
Function of peroxisomes (2)
1. Detoxification of O2 radicals2. Breaks down fatty acids (catabolic)
251
List the 3 cells in which we find cell wall and name them: (3)
1. Plants: cellulose2. Fungi: Chitin3. Bacteria: peptidoglycan
252
Do bacteria’s have cytoskeleton?
NOOOO
253
Which type of cell is cytoskeleton present?
Eukaryotic cells
254
What are the filaments of cytoskeleton made of?
Proteins!
255
What are the 3 types of filaments that cytoskeleton is made of?
Microfilaments, Intermediate filaments, Microtubules
256
Microfilaments are … (3)
1. Made of actin2. Dynamic (grow and shrink)3. Associated with PM (cortex)
257
Functions of microfilamments (4)
1. Shape the microvilli2. Cell movement ➡️ phagocytosis3. Muscle contraction ➡️ actin-myosin4. Cell division ➡️ Actomyosin ring during cytokinesis
258
Functions of intermediate filaments: (3)
1. strength and shape of cells2. anchors organelles (holds them in place)3. form nuclear lamina [Image]
259
Are intermediate filaments dynamic?
No, they are flexible
260
Microtubules grow at _________ (3)
1. centrosomes2. microtubules organizing center (MTOC ~ plant cells) 3. basal bodies (base of flagella and cilia)
261
Functions of microtubules: (3)
1. Shape and movement ➡️ flagella and cilia2. cell division ➡️ forms mitotic spindle (Kinetochore MT and polar MT)3. organelle movement ➡️ “tracks” for vesicles & organelles
262
Are MT dynamic?
YES
263
Does cell division require energy?
Yes, it requires ATP hydrolysis
264
Does cell movement require energy?
Yes, it needs ATP hydrolysis!
265
Which type of cell(s) is PM present in?
Prokaryotic and Eukaryotic
266
Which type of cell(s) is nuclear envelope and nucleus present in?If not present name the alternative, if there is.
❌ Prokaryotic ➡️ not true nucleus, nucleoid✅ Eukaryotic
267
Which type of cell(s) are chromosomes (w/ DNA) present in?
Prokaryotic: single circular DNA molecule in nucleoidEukaryotic: many made of chromatin in nucleus
268
Which type of cell(s) is nucleolus present in?
ONLY eukaryotic
269
Which type of cell(s) are ribosomes present in?
BOTH
270
Which type of cell(s) is the endomembrane system organelles present in?
ONLY eukaryotic cells
271
Which type of cell(s) is microtubules present in?
ONLY eukaryotic cells!! SINCE PROKARYOTIC CELLS DONT HAVE CYTOSKELETON!
272
Which type of cell(s) are centrioles present in?
Only animal cells
273
Which type of cell(s) is basal bodies (flagella and cilia) present in?
ONLY animal [Image]
274
Which type of cell(s) is flagella and cilia present in?
Prokaryotic: flagellum not covered by PMEukaryotic only animal NOT IN PLANT (because of cell wall)
275
Which type of cell(s) is central vacuole present in?
Plant cells ONLY
276
Which type of cell(s) is cell wall present in?
Prokaryotic and ONLY plant cells
277
Which type of cell(s) is capsule present in?
ONLY prokaryotic
278
Cell division in prokaryotic and eukaryotic?
Prokaryotic ➡️ binary fissionEukaryotic ➡️ mitosis
279
Properties of membrane (5)
1. Flexible2. Self-healing3. Fluid4. Can fuse with each other5. Selectively permeable
280
What’s the direction of the phospholipids movements in the membrane?
Lateral ➡️ Sideways
281
What does the selective permeability of membrane help with?
Maintaining homeostasis
282
What are membrane permeable to? (3)
- hydrophobic molecules- non-polar molecules- gas and steroids
283
What are membrane impermeable to?
- hydrophilic molecules- polar/charged- ions, water, sugars, macromolecules
284
What are integrins?
Membrane associated proteins in the CM that attaches cells to their surroundings [Image]
285
What does integral proteins mean?
proteins found in the CM
286
Functions of membrane proteins (6)
1. Attachment and anchoring (integrins)2. Transport3. Enzymes 4. Receptors5. Cell connections6. recognition
287
Name the 5 small molecules that are transported across the membrane:
ions, aa, sugars, water, gases
288
What are the 2 factors that affect transport?
1. Concentration of solutes2. Size and polarity
289
Simple diffusion: (2)
1. [hi] ➡️ [low]2. non-polar molecules (lipid soluble) ➡️ gases and steroids
290
Water movement across membrane: (3)
1. Osmosis by aquaporins2. [low] ➡️ [hi] (solute)3. Hypo ➡️ Hyper
291
Facilitated diffusion:
- [hi] ➡️ [low]- hydrophilic molecules1️⃣ channels- ions and water- fast- donut form (always open)2️⃣ transporters- large and polar (sugars and aa)- slow- changes shape
292
Name the 3 type of passive mechanics
1. Simple diffusion2. Osmosis3. Facilitated diffusion
293
What does passive transport mean?
doesn’t require energy
294
Why type of solution do animal and plants cells prefer?
Plant: Hypotonic (less water inside so that water form outside of the cell comes inside) ➡️ TurgidAnimal: Isotonic ➡️ no net movement of water
295
Explain the 3 stages of solutions for both animal and plant cells and give the names of each one:
1. Hypertonic ➡️ water leaves the cell, cell shrinks- animal: crenation- plant: plasmolysis2. Isotonic ➡️ No net mvt of water- animal: normal- plant: flaccid3. Hypotonia ➡️ Water comes into cell, brusting- animal: Lysed (hemolysis)- plant: trugid
296
List the 2 subgroups of active mechanism:
1. Active transport2. Bulk transport
297
what does active transport imply?
requires energy
298
Active transport (3)
1. Against gradient: [low] ➡️ [hi]2. Pumps (sodium/Potassium Pump) ➡️ Requires hydrolysis of ATP3. Co-transporters
299
Electrogenic pumps
creates membrane potential/charge separation
300
Co-transport
transport solute against gradient with help of co-transport ion down gradient
301
briefly explain the sodium potassium pump
1. The charge outside the cell is more positive than inside the cell2. To be activated and moved the pump needs an ATP (energy currency)3. Then 3 Na2+ from inside the cell gets transported outside the cell where [Na] is higher4. Then 2 K+ will come from outside and transported inside the cell where its concentration is higher
302
Bulk transport means ________
transport of large molecules like proteins in and out of cell
303
What are the two types of bulky transport?
1. Exocytosis (vesicle fuses with PM)2. Endocytosis (formation of vesicles)
304
What are the 3 types of endocytosis?
1. Phagocytosis (cell eating) ➡️ large food molecules/bacteria 2. Pinocytosis (cell drinking) ➡️ dissolved material3. Receptor-mediated endocytosis (uptake of cholesterol) ➡️ Picky only specific molecule of receptor can be brought inside
305
Which type of cell division is responsible for asexual reproduction, growth, development and repair?
Mitosis
306
What type of cells do mitosis produce?
identical somatic cells (body cells)
307
Asexual reproduction (3)
1. One parent2. Offsprings are identical3. No gametes
308
What are the 3 key events of mitosis?
1. DNA replication➡️ 2 sister chromatids Per chromosoem➡️ Sister chromatids: 2 identical dna molecules attached by centromere2. Mitosis ➡️ chromosomes divided3. Cytokinesis
309
What are the 4 phases of the cell cycle and what happens in each one?
G0: quiescence ➡️ “cell pause”G1: Gap phase 1 ➡️ Cell grows, checkpointS: synthesis ➡️ DNA replication (chromosomes gains 2 sister chromatids) by DNA polymerase)➡️ duplication centrosomes/MTOC (poles of mitotic spindle)G2: Gap phase 2 ➡️ preparation for mitotic phase
310
What is the G1 checkpoint?
✅ monitors cell size✅ environmental conditions✅ if ready to divide
311
In the S phase how many chromosomes and chromatids do humans have?
46 chromosomes but 92 chromatids
312
Which phases make the interphase?
G1, S and G2
313
During interphase are individual chromosomes visible?
NO
314
What are the sub-phases of Mitosis?
P ➡️. ProphaseP ➡️ PrometaphaseM ➡️ MetaphaseA ➡️. AnaphaseT ➡️. Telophase (cytokinesis)
315
Prophase/prometaphase:
➡️ chromosomes condense into X shape➡️ Nucleolus dissapears➡️ Nuclear envelope disappears➡️ Centrosome are at opposite poles➡️ Mitotic spindle captures chromsomes
316
Metaphase: (3)
“M” ➡️. Middle➡️ Chromosomes align at the metaphase plate➡️ Kinetochore MT attach at the chromosomes centromere➡️ polar MT overlap [Image]
317
Anaphase:
”A” ➡️ Away➡️ Sister chromatids are pulled apart from each other to opposite poles by the reducing of polar Mt overlap (elongates spindle) and the kinetochore that becomes shorter pulls the sisters apart
318
Telophase:
”T” ➡️ Two✅ Nuclear envelope reforms ➡️. 2 nuclei appear ➡️ Nucleolus reappears✅ Chromosomes decondenses ➡️ spindle disappears
319
At which phase does cytokinesis occur?
Telophase!
320
Cytokinesis from animals and plants:
ANIMAL: cleavage furrow forms ➡️ Pinching CM by actomyosin ring (microfilaments)PLANT: cell plate froms [Image]
321
What is cell division called in bacteria?
binary fission
322
what are the 5 steps of binary fission?
1. Single circular chromosome is replicated at the origin of replication2. Cell elongates and two copies move to opposite ends3. Cell membrane grows inward4. Cell wall forms5. Cell splits [Image]
323
What are the 3 checkpoints that monitor the cell cycle?
1️⃣ G1 Checkpoint → Checks if the cell is big enough & has nutrients.2️⃣ G2 Checkpoint → Checks if DNA was copied correctly.3️⃣ M Checkpoint → Ensures chromosomes are attached to spindle fibers before division.
324
What happens at the G1 checkpoint, what stops division of cells (4)?
G1 stops the cell division if:➡️ cell too small, lacks nutrients➡️ isn’t attached to a surface (anchorage dependence)➡️ once the surface is covered with cells➡️ dna damage
325
What happens when DNA damage is beyond repair?
cells undergo apoptosis
326
What is apoptosis?
programmed cell death
327
Steps of Apoptosis:
1️⃣ DNA fragmentation - chromatin condenses and nucleus fragmentsEnzyme: nucleases2️⃣ Formation of apoptotic bodies (blebs)- cellular fragmentationEnzyme: proteases3️⃣ Phagocytosis of apoptotic bodiesMacrophages: White blood cells [Image]
328
Does the cell lyse (burst) during apoptosis?
No!
329
Nucelase:
Break down nucleic acid (DNA)
330
Protease
Enzyme that breaks down proteins
331
What does the mitochondria activate after being triggered by a signal (apoptosis)
CASPASES✅ Caspases = Enzymes that control apoptosis✅ They act as proteases & nucleases‼️WITHOUT CASPASES APOPTOSIS WOULDN'T HAPPEN
332
What is the main difference between necrosis and apoptosis?
Necrosis is an accidental cell death ➡️ tissue damageApoptosis is a programmed cell death ➡️ signals
333
What happens in necrosis?
Cell lysis (bursts) ➡️ Plasma membrane breaks ➡️ Organelles spills out [Image]
334
What does necrosis trigger?
inflammation
335
What happens in apoptosis?
DNA condenses and fragments ➡️ Cells break into apoptotic bodies ➡️ macrophages eats the bodies (phagocytosis)
336
Does apoptosis trigger inflammation?
NO
337
What are the internal (2) and external triggers (2) for apoptosis?
INTERNAL:1. DNA damage2. Protein misfolding in EREXTERNAL:1. Death signals from nearby cells2. Immune cells detect infected cells
338
What happens if G1 checkpoint fails to work?
uncontrolled growth and division of cells ➡️ Creation of cancer cells
339
Which type of cell division is related to reproduction?
meiosis
340
What are the advantages of sexual reproduction? (2)
1. Variation in offsprings2. Increase survival of population
341
Sexual reproduction (3)
1. Gametes2. Two parents3. Different offsprings
342
What are homologous pairs? (5)
1. Pair of chromosomes, one from each parent2. Same length and shape3. Same banding patterns4. Same order of genes5. Similar dna sequences
343
What is a karyotype?
display of chromosomes in metaphase ➡️ shows banding pattern
344
What is diploid and haploid?
✅ Diploid (2n) → Cells with two sets of chromosomes (one from each parent).• Humans: 46 chromosomes (23 pairs)• 2n = 46 → n = 23✅ Haploid (n) → Cells with one set of chromosomes (gametes: sperm/egg).• Humans: 23 chromosomes.
345
Do somatic cells have haploid or diploid chromosomes?
Diploid (2n)➡️ two copies of every chromosome➡️ Human 2n = 46 [Image]
346
Are gametes cells haploid or diploid?
Haploid (n)➡️ Because gametes are either sperm or egg cells therefore they need to be haploid because they’ll need to combine that for fertilization➡️ 1 copy of every chromosome [Image]
347
Identify each letter and number [Image]
A ➡️ Haploid (n)B ➡️ Diploid (2n)1 ➡️ Ovary2 ➡️ Testis3 ➡️ Meiosis4 ➡️ sperm (n)5 ➡️ haploid gametes (n=23)6 ➡️ Egg (n)7 ➡️ fertilization8 ➡️ Diploid zygote (2n =46)9 ➡️ Mitosis and development10 ➡️ Multicellular diploid adults (2n = 46)
348
By how many does meiosis divide the number of chromosomes
BY HALF
349
If both parents are diploid (2n), what will be the gametes formed?
haploid (n)
350
What happens during fertilization?
The gametes unite to restore the diploid number n + n = 2n
351
How many nuclear divisions does Meiosis have?
2 ➡️ Meiosis I and Meiosis II
352
True or False, DNA replication occurs twice
False, ONLY ONCE during interphase
353
What do we call when 2 homologous chromosomes pair up?
synapsis
354
What happens in meiosis I?
1. Separation of homologous chromosomes 2. Number of chromosomes reduced 2n ➡️ n3. Two daughter cells [Image]
355
What happens in meiosis 2?
1. The sister chromatids seperates2. Four daughter cells ➡️ Gametes [Image]
356
When does the “crossing over” occur?
prophase 1
357
What do we call the formation of 4 sisters ?
Tetrad
358
Prophase I (3)
1. Chromosomes condense2. Synapsis ➡️ Homologous chromosomes pair up3. Crossing over ➡️ Exchange segments of dna
359
Metaphase I (3)
1. Alignment of tetrads along the equator2. Homologous chromosomes are held tgt by chiasmata ➡️ Crossing over site3. Independent assortment ➡️ Homologous chromosomes align randomly [Image]
360
Anaphase I
homologous chromosome pairs are split we end up with chromosomes only (sister chromatids)
361
Telophase I:
1. Chromosomes decondenses (spindle bye bye and nuclear envelope hi)2. Not necessarily cytokinesis3. Nuclei are haploid [Image]
362
prophase II
1. Chromosomes recondenses ➡️ Centriole duplications, nuclear envelope bye bye and spindle reforms
363
metaphase II
chromosomes align at equator
364
Anaphase II
The “sister” chromatids are separated ➡️ not real sister chromatids because of crossing over
365
Telophase II
1. Chromosomes decondenses 2. cytokinesis ➡️ 4 different haploid cells➡️ 4 different haploid nuclei reform
366
what are factors that can increase variation in traits of offsprings? (2)
1. Crossing over ➡️ Prophase I2. Independent assortment ➡️ Metaphase I
367
Crossing over happens for all _______________
homologous chromosomes pair
368
independent assortment
1. During metaphase I2. How homologous chromosome pairs (tetrads) randomly line up at equator
369
Which type of cells are involved in mitosis and meiosis?
Mitosis: somatic cells, embryonic Meiosis: germ cells (gametes)
370
What’s the number of division in mitosis and meiosis?
Mitosis = 1Meiosis = 2
371
Which type of cells division involve crossing over at prophase I?
Meiosis only
372
Which type of cells division does independent assortment occur?
Meiosis only
373
How many tImes is DNA synthesized (replicated) in mitosis and meiosis?
ONLY ONCE at the S phase of interphase
374
How many cells are produced at the end of each cell division?
Mitosis = 2Meiosis = 4
375
Whats the ploidy (haploid/diploid) of cells reduced in each type of cell division?
Mitosis = diploid (2n = 46)meiosis = haploid (n=23)
376
Which number of meiosis is very similar to mitosis?
Meiosis 2 ➡️ sister chromatids are seperated [Image]
377
Whats the formula to calculate the number of different possibilities of gametes based only on independent assortment?
2^n where n = # of homologous chromosomes pairs Ex: humans have 23 pairs of chromosomes (n=23) ➡️ 2^23
378
Let’s say the diploid number is 2n =2 ➡️ find the number of chromosomes and chromatids in each phase of meiosis (G1, P1, P2, gametes)
G1:➡️ chromosomes = 2➡️ Chromatids = 0 (chromatids is when sister chromatids are attached by their centromere)P1:➡️ Chromosomes = 2➡️ Chromatids = 4P2:➡️ Chromosomes = 1➡️ Chromatids = 2Gametes:➡️ Chromosomes = 1➡️ chromatids = 0
379
Let’s say the diploid number is 2n =2 ➡️ find the number of chromosomes and chromatids in each phase of mitosis (G1, P, M, A, T)
G1:➡️ chromosomes = 2➡️ Chromatids = 0P:➡️ Chromosomes = 2➡️ Chromatids = 4M:➡️ Chromosomes = 2➡️ Chromatids = 4A:‼️➡️ Chromosomes = 4 ➡️ Chromatids = 0T:➡️ Chromosomes = 2➡️ Chromatids = 0
380
What kind of rxn is DNA replication?
➡️ synthesis rxn➡️ Anabolic ➡️ requires energy
381
what is a special characteristic of DNA replication?
semi-conservative (one old strand and one new)
382
When does DNA replication happen?
S phase
383
Replication bubble: (2)
↔️ Bidirectional (bubble)✂️ 2 replication fork moves in opposite directions (daughter strands) [Image]
384
in which direction is DNA synthesized?
5’ ➡️ 3’ (for RNA as well!)
385
What does primer (RNA) do?
provides 3’OH that allows DNA replication‼️ very important
386
What do we call the replication towards the fork?
Leading strand ➡️ continuous
387
What do we call the replication away from the fork?
Lagging strand ➡️ Discontinuous, Okazaki fragments
388
Steps of DNA replication in order (6)
1. Helicase (unzips DNA by breaking H bonds) + Topoisomerase (avoids the supercoiling tendency)2. SSDNA binding proteins (sticks to the parental strand to prevent tendency of DNA to rezip)3. Primate (RNA primer) ➡️ 3’OH that allows DNA replication4. DNA polymerase III (adds DNA in 5’ ➡️ 3’) + proofreading makes sure no mistake in replication⭐️ for lagging strand the steps 3 & 4 are repeated with RNA primer being placed closer to the fork each time ➡️ forms Okazaki fragments5. DNA polymerase I (chews on RNA primer and replaces it w/ DNA)6. Ligase (glues the Okazaki fragments of the lagging strand together to from continuous strand)
389
When does DNA replication happen in eukaryotic and prokaryotic cells?
Eukaryotic ➡️ S phaseProkaryotic ➡️ Continuously
390
How many replication origins do each type of cells have?
Eukaryotic ➡️ Multiple origins per linear chromosomeProkaryotic ➡️ Single origin per circular chromosome [Image]
391
What problem do we encounter in eukaryotic cells when replicating DNA?
the linear ends of chromosomes gets shorter after replication
392
Whats the solution to the replication problem for eukaryotic cells?
telomeres
393
Whats the problem with DNA replication in prokaryotic cells?
improper separation of replicated chromosomes
394
Do we have a solution for dna replication problem in prokaryotic cells?
No :(
395
What are telomeres?
1. non-coding repeats of hexanucleotide (AGGGTT) at both ends of linear chromosomes2. enzyme: telomerase adds telomere sequences
396
Whats the role of telomeres?
protect chromosomes from damage and loss of genetic information
397
Which cells maintain telomerase (4) and which ones don’t (1)?
✅ cancer, germ, stem, embryonic cells❌ somatic cells
398
What does an absence of telomerase lead to?
shortening of telomeres
399
Which cells are shortening associated with?
aging cells
400
What does the hayflick limit state?
When a chromosomes reach a critical short length the cell stops dividing
401
true or false: Cancer cells have high telomerase activity
True, that’s why they can divide infinitely, telomeres don’t get shorter
402
How many telomere do we find in one linear chromosome?
1 DNA w/ 2 telomeres
403
How many telomeres do we find in one metaphase chromosome?
4 telomeres BECAUSE• Each chromosome = 2 sister chromatids (2 DNA molecules).• Each chromatid has 2 telomeres, so there are 4 telomeres per chromosome. [Image]
404
Haploid vs Diploid in meiosis and mitosis
[Image] [Image] [Image] [Image]
405
True or False: Binary fission creates 2 identical daughter cells
true
