Cell as the Basis of Life A2.2 (Cell Structures) Flashcards

1
Q

Outline the three basic tenets of the cell theory

A

1.) All living things are composed of cells

2.) The cell is the basic unit of life

3.) Cells come from preexisting cells

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2
Q

Outline the reason why the cell is the basic unit of life.

A

Smallest structural unit that is capable of using energy to sustain itself in a highly ordered state

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3
Q

Outline the reason why we have multiple types of cells for multi-cellular organisms

A

it’s specialization (for efficiency)

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4
Q

Outline the evidences for the basic tenets of the cell theory

A

Cell’s the basic unit of life: plants, animals, fungi, protists, bacteria contained at least one or more cell

All living things composed of cells: Subcellular components do not perform the same processes as full cells

All cells came from pre-existing cells: No evidence of spontaneous generation

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5
Q

Outline the type of reasoning that uses specific (observation) -> general conclusion

A

Inductive reasoning

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6
Q

Outline what we mean when we say deductive reasoning

A

General premises -> specific conclusion
(e.g. using cell theory tenets to make a specific conclusion)

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7
Q

Define theory in daily usage

A

A guess — has doubt

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8
Q

Define theory in scientific usage

A

Shown true through repeated observations and experiments, STILL CAN BE QUESTIONED BTW, just no current doubt (but has a degree of uncertainty??)

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9
Q

Define “well substantiated”

A

Lots of evidence

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10
Q

Define “based on a body of facts”

A

not opinion

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11
Q

Define “through observation and experiment”

A

Rigorous testing and use of scientific method

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12
Q

If given a picture, outline which formula would you use for Magnitude

A

M = I/A

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13
Q

Outline why HP and LP are relative?

A

Due to the given.

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14
Q

Outline what is considered as an image.

A

The actual size but magnified for us to see w/ or w/o a microscope
e.g.: what we see using a microscope, drawings, our rulers (because how can we measure the actual size using a ruler only when the organisms we study are usually tiny?), etc.

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15
Q

How should scientific names be written

A

-If written, underlined
-If typed, italicized
- The genus name should be capitalized
(e.g. Allium cepa)

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16
Q

Describe the methods of determining the field of view diameter (FOV) using a ruler

A

Method 1: Place a transparent metric ruler

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17
Q

Outline the two types of cells.

A

There’s eukaryotic and prokaryotic

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18
Q

List the common structures of all cells

A
  • Plasma membrane
  • Cytoplasm
  • DNA
  • Ribosomes
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19
Q

Describe the plasma membrane

A

It is a bilayer formed from phospholipids
- Due to their amphipathic nature (hydrophilic and hydrophobic)

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20
Q

Describe what a cytosol is.

A

It is the liquid part of the cytoplasm.
- Gel-like fluid substance made of water and many dissolved solutes (sugars, amino acids, proteins …)

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21
Q

What does the scale bar refer to?

A

Image size

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22
Q

Give the parts of the microscope

A
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23
Q

Outline the process of preparing a wet mount

A
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24
Q

Define staining and give examples

A
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25
Q

Define “resolution”

A

Smallest interval distinguishable by the microscopelevel of detail visible in an image created by the instrument

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26
Q

Outline the benefits of a compound light microscope

A
  • Ease of use
  • Less expensive to buy
  • Can observe dead or living cells in color
  • Cell movement can be studied
  • Quick specimen prep (minutes to hours)
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27
Q

What does a compound light microscope do to magnify images?

A

Bend light

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28
Q

What does an electron microscope do to magnify images?

A

Use electron beams focused by electron magnets to magnify and resolve

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29
Q

Outline the disadvantages of a compound light microscope

A
  • Maximum magnification of 1500X (can only see bacteria)
  • low resolving power (0.25 micrometer to 0.3 micrometer)
  • low level of detail and smaller image size
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30
Q

Define begets

A

Gives rise to

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31
Q

Outline the structures common to all cells:

A
  • Plasma membrane
  • Cytoplasm
  • DNA
  • Ribosomes
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32
Q

Give what carrier of genetic information do living things use today

A

DNA

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33
Q

Describe the functions and sizes of ribosomes in BOTH prokaryotes and eukaryotes

A
  • Catalyzes the synthesis of polypeptides during translation
  • Composed of two subunits that come together to form a functioning structure
  • size of eukaryote ribosomes (80s) > size of prokaryote ribosomes (70S)
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34
Q

Distinguish the features of a prokaryotic cell from a eukaryotic cell. (SEP AFTER)

A

S(ize), M(embrane)o(rganelles), R(eproduction), C(ell) w(all), D(NA) l(ocation), M(ovement) F(lagella), D(NA) P(roteins), R(ibosomes), P(lasmids), U(ni-) M(ulti-)

S, Mo, R, Cw, Dl, Mf, Dp, R, P, U/M

Smart Moms rearing cutware Delicious Mof Deplacement Reception Poetic United/Multiple

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35
Q

Outline and describe the structures of the prokaryotic cell and its functions

A
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36
Q

Define and explain nucleoid

A

Prokaryotic

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37
Q

Define what we mean when we say that prokaryotic cell DNA is “naked”

A

DNA is not associated with proteins.

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38
Q

In eukaryotes, how does the DNA “associate itself with proteins?

A

Via nucleosomes
- which is when DNA coiled around proteins called histones.
(This doesn’t happen in prokaryotic cells as they are “naked”, they don’t have membrane and thus have no “histones”/protein to coil around in)

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39
Q

Identify the nucleoid, cell wall and plasma membrane of this prokaryotic cell

A
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40
Q

Outline the common structures of Eukaryotic cells (not necessarily seen in both plant and animal cells)

A
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41
Q

Describe the nucleus (eukaryotic cell as nucleoid is for prokaryotic)

A
  • Contains DNA
  • Contains nucleolus, a spherical structure that produces ribosomes
  • Has a double membrane with pores through it
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42
Q

Explain the structures of ribosomes and its function (both prok and euk).

A
  • catalyzes the synthesis of polypeptides during translation (common function)
  • composed of two subunits that come tgt to form a functioning structure
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43
Q

In eukaryotes, give the two categories of ribosomes

A

1.) Free = floating in cytoplasm, synthesizing polypeptides (the blue string) used within the cell

2.) Bound = attached to the rough endoplasmic reticulum (green), synthesizing polypeptides that are secreted from the cell or become integral proteins in the cell membrane

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44
Q

Describe the structure and functions of the Rough Endoplasmic Reticulum [4]

A
  • a series of flatten membranous sacs
    -“membranous” because it carries proteins alike the cell membrane
  • Play a central role in the synthesis and transport of polypeptides.
    • Like amazon. Creates products and ships it.
  • has bound ribosomes which synthesize the polypeptide and release it to the inside of the RER.
  • the RER membrane is continuous with the nuclear envelope, which surrounds the cell nucleus
    • basically attached to outside of nucleus.

(Think of it like Amazon. And the bound ribosomes are the employees)

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45
Q

Describe the smooth endoplasmic reticulum

A
  • a series of connected flattened membranous sacs that are continuous with the RER.
  • In contrast to the RER, smooth endoplasmic reticulum lacks ribosomes and is not involved in protein synthesis
  • Main Function*: synthesis of phospholipids and cholesterol (lipids)
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46
Q

Describe the golgi apparatus’ functions

A
  • modify polypeptides into their functional state
  • the golgi sorts, concentrates and packs their proteins into vesicles
    • like delivery centers — the drop off points of Amazon (RER) ??
    • vesicles are like the package
  • depending on the contents, the vesicles are dispatched into one of three destinations:
    • Within the cell, to lysosomes (synthesized by free ribosomes)
    • The plasma membrane of the cell (synthesized by bound ribosomes)
    • Secretion to the outside of the cell via exocytosis (synthesized by bound ribosomes)
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47
Q

Describe vesicles

A

Membrane bound sacs that contain and transport materials within cells.

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48
Q

Explain the two types of vesicles

A

1.) Transport vesicles - move molecules between locations inside the cell by budding off one organelle compartment.

2.) Secretory vesicles - secrete molecules from the cell via exocytosis.
- They are also *how new phospholipids are added to the cell membrane.

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49
Q

Describe the lysosome

A
  • small spherical organelles, enclosed by a single membrane.
    • aka suicide bags
  • contain enzymes that work in oxygen-poor areas and lower pH
  • enzymes digest large molecules (function) to degrade and recycle the components of the cell’s own organelles when they are old or damaged, or if the cell is ‘starving’ in the absence of nutrients (purposes)
    • lysosome: the “fix-it”/feeding company; the enzymes: the handy men
  • also has an immune defense function by digesting pathogens that have been engulfed by phagocytes.
    • lysosome also doubles as a security company! They contain threats engulfed by phagocytes!
    • phagocytes: security guards
    • pathogens: intruders (e.g. harmful bacteria)
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50
Q

Describe mitochondria

A
  • mitochondria apadted for production of ATP by aerobic cellular respiration
  • mitochondrion is surrounded by a double membrane
    • because according to endosymbiosis, the ancestor of the mitochondria (a prokaryote cell) had its own membrane before being swallowed
  • mitochondria evolved by endosymbiosis
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51
Q

Describe chloroplasts

A
  • adapted for photosynthesis, converts sunlight to glucose via water and carbon.
  • chlorophyll, light absorbing pigments, give the chloroplast its characteristic green color.
  • chloroplasts evolved by endosymbiosis.
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52
Q

Describe vacuoles in plant cells

A

Purpose: water storage

  • In mature plant cells, a central vacuole contains 30% - 90% of the volume of the cell.
  • In addition to water storage, the main role of the vacuole is to maintain turgor pressure against the cell wall
  • Turgor pressure = mechanism the plants use to remain upright
    • forces cell wall to protect the plant cell from the pressure and thus maintain posture by fighting pressure (??)
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53
Q

Describe cytoskeleton

A

IT IS NOT AN ORGANELLE (even if its present within both prokaryotic and eukaryotic cells)

It is a “backbone” or “skeleton” in the sense that it:

  • helps cells maintain their shape
  • organizes cell parts
  • enables cells to move and divide (because it is made from microtubules)
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54
Q

Outline the components working together to form the cytoskeleton

A
  • Several different components work together to form the
    cytoskeleton, including:
  • microtubules
  • actin filaments
  • intermediate filaments
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55
Q

Describe/explain what are microtubules

A

Polymers of a protein called tubulin and form part of the exoskeleton
-Function: intracellular transportation of organelles and separation of chromosomes
- e.g.: in meiosis?

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56
Q

Explain/describe the centrioles

A

Paired cylindrical-shaped group of organelles composed of nine groups of three microtubules organized with radial symmetry

Functions:
- arrangement of the miotic spindle during cell division.
- anchor points for microtubules in the cytoplasm and for cilia and flagella (which modified to become a basal body)

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57
Q

distinguish and compare Cilia and Flagella

A

Similarities:
- Extensions from the cell surface which aid in cell movement (think of the sperm tell as an example)

Differences:
- Cilia: protrusions (the “tails”) are short and numerous
- Flagella: longer and less numerous.

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58
Q

Outline the shared processes of life

A

Homeostasis, Metabolism, Nutrition, Movement, Response to Stimuli, Excretion, Growth, Reproduction

MH GRREMN

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59
Q

Explain and define Homeostasis

A

Definition: maintaining an equilibrium/balance
- In living organisms, being able to be in homeostasis means to have a stable chemical environment inside despite their external environment
- Can be seen in all organisms

60
Q

Define and explain metabolism

A

Definition: sum of all the chemical reactions in a cell.
- Can include polymerization AND the turning of polymers into energy and smaller molecules
- One of the reasons why viruses aren’t “living things”, they can’t metabolize.

61
Q

Distinguish anabolic and catabolic reaction

A

Anabolic: energy + smaller molecules (monomers ??) => polymers

Catabolic: larger molecule => energy + smaller molecules (monomers)

62
Q

Define and explain nutrition

A

definition: obtaining energy (to do processes) and matter (to get nutrients ??), basically using food to support life

63
Q

Distinguish the two types of nutrition

A
  • autotrophs - uses external energy (sun) to synthesize inorganic -> carbon compounds
  • heterotrophs - gets carbon carbons to synthesize from OTHER organisms.
64
Q

Define movement

A

Definition: changing location

65
Q

Describe the two types of organisms according to mvmt.

A

1.) Sessile organisms - stay in one place

2.) Motile organisms - mobile

66
Q

Define excretion

A

Definition: metabolic waste (e.g. poo) is eliminated from an organism

67
Q

Describe how excretion is seen in living orgs

A

(Reminder! Excertion doesn’t always mean poop and pee, can also mean exhaling of carbon dioxide)

  • excretion primarily occurs via lungs
  • in many plants, excretion occurs via leaves, roots and stem
  • excretion occurs through the cell membrane, which is one reason cells must have a large surface area to volume ratio (to excrete the cell waste)
68
Q

Define growth (and development

A

Increase in size and mass of an organism
- Sub-topic to growth: development - transformation of the organism (e.g. metamorphosis or seed -> tree, could also be mitosis of amoeba)

69
Q

Describe the process of “response to stimuli”

A

To recognize and respond to changes in environmental conditions

70
Q

Describe the process of reproduction

A

life will create more life

71
Q

Describe the two types of reproduction

A

1.) Sexual reproduction - 2 parents, fusion of haploid cells
- meiosis.
- due to more parents, there’s more genetic variation

2.) Asexual reproduction - 1 parent only.
- genetically identical offspring
- binary fission and mitosis

72
Q

Could unicellular organisms carry out all the processes of life?

A

Yis (bc they have cell)

73
Q

Outline how paramecium displays the basic processes of life

A
74
Q

Outline how paramecium displays the basic processes of life (pt 2 SYNTHESIZE)

A
75
Q

Outline how chlamydomonas displays the basic processes of life (SYNTHESIZE)

A
76
Q

Outline how chlamydomonas displays the basic processes of life (SYNTHESIZE)

A
77
Q

Define “Eukaryota”

A

The domain of Eukaryota is a domain (classification of living things)
- includes: eukaryotic cells

78
Q

Describe the creatures under domain Animalia

A

Theyre called “animals”, largest kingdom
- multicellular eukaryotes w/o a cell wall
- holozoic (eat other organisms with internal digestion of nutrients, does this include plants?)

79
Q

Describe what can be under “Fungus’

A
  • Eukaryotes with a cell wall made of chitin
  • uni- OR multi-cellular
  • MOSTLY saprotrophs
    • secrete digestive enzymes into their environment and then absorb the nutrients into their body after there has been external digestion
  • some are parasitic
  • principal decomposers
80
Q

Describe the kingdom Plantae

A

“plants” - multicellular eukaryotes with a cellulose cell wall
- autotrophs (make their own food)
- feel almost all heterotrophs
- 300,000 species of plants known

81
Q

Outline the similarities in Eukaryota Cell Structure

A

Among animal, fungi and plant cells..

82
Q

Explain the differences in cell structure in relation to plastids

A

Plastids - any of a class of small organelles, such as chloroplasts, in the cytoplasm of plant cells, containing pigment or food.

83
Q

Explain the differences in cell structure in relation to cell walls

A

Cell wall - external to plasma membrane, provides strength

84
Q

Explain the differences in cell structure in relation to vacuoles

A
85
Q

Explain the differences in cell structure in relation to centrioles

A
86
Q

Explain the differences in cell structure in relation to cilia and flagella

A
87
Q

Distinguish between trends and discrepancies

A

1.) trend - typical, prevailing tendency
- give predictions

2.) discrepancy - atypical, does not fit the trend
- lead to scientific questions

88
Q

Outline three examples of trends

A
  • cells are small
  • all living things are composed of true cells
  • cells come from pre-existing cells

basically cell theory + that there are typical cell structures

89
Q

Explain the discrepancy of red blood cells

A

It is a eukaryotic cell without a nucleus or mitochondria!
- what makes it eukaryotic?: they are produced by a eukaryotic organism and to begin with they do contain a nucleus
- for what purpose?: to carry more oxygen

90
Q

Describe the discrepancy of the aseptate fungal hyphae

A
  • What is that?: When Fungal hyphae are not made of clearly defined indv. cells, they’re called Aseptate hyphae
  • Aseptate hyphae are not made of clearly defined individual cells, rather continuous structures with multiple nuclei
  • for something to be a living thing, it must have a cell but how about something with multiple organelles but no clearly defined cell?
91
Q

Describe the discrepancy of skeletal muscles

A

A very large cell with more than one nucleus

92
Q

Define sieve tube elements

A

specialized plant cells that are part of the phloem, transports organic compounds during photosynthesis

93
Q

Outline the discrepancy of phloem sieve element

A

A eukaryotic cell without organelles

94
Q

Explain why the phloem sieve tube element as no nucleus and organelles?

A

To have more space for the transport of phloem sap (resembles the rbcs reasons for having no nuc a lil!)

95
Q

Define micrographs

A

A photograph taken through a microscope to show the magnified image.

96
Q

Distinguish the two different types of micrographs for prokaryotic cells

A
97
Q

Distinguish the two different types of micrographs for plant cells

A
98
Q

Distinguish the two different types of micrographs for animal cells

A
99
Q

What part of the cell is this?

A

Nucleus.

100
Q

What part of the cell is this?

A
101
Q

What part of the cell is this?

A

Smooth ER

102
Q

What part of the cell is this?

A

Golgi apparatus

103
Q

What part of the cell is this?

A

Lysosome

104
Q

What part of the cell is this?

A

Mitochondria

105
Q

What part of the cell is this?

A

free ribosomes - synthesize polypeptides during translation

106
Q

What part of the cell is this?

A

chloroplasts

107
Q

What part of the cell is this?

A

Vacuole

108
Q

What part of the cell is this?

A

Vesicles

109
Q

What part of the cell is this?

A

Centrioles

110
Q

What part of the cell is this?

A

NOT AN ORGANELLE — Cytoskeleton

111
Q

What part of the cell is this?

A

Cilia

112
Q

What part of the cell is this?

A

Flagella

113
Q

What part of the cell is this?

A

Cell Wall

114
Q

What part of the cell is this?

A

Cell membrane

115
Q

What part of the cell is this?

A
116
Q

How to draw and label a drawing of something viewed under the microscope?

A
117
Q

HOW TO DRAW ANIMAL CELL

A
118
Q

HOW TO DRAW PLANT CELL

A
119
Q

Define ultrastructures

A

cellular structures (something that is structured to be a cell) that are to small to be seen by a light microscope
- Includes only prokaryotic cells (aka bacteria and archaea)

120
Q

Give and explain the reason why the golgi apparatus and the endoplasmic reticulums (both of them) and the nuclear envelope have that curvedshape

A

Infolding
- evolved from the inward folds of ancestral prokaryotic cells (maybe relate this with the characteristics of prok. cells).
- Allows for more complex chemical reactions in different compartments (explain pls miss??)

121
Q

Explain how ”endosymbiosis” explained the origin of mitochondria

A

Hypothesis: They were once aerobic bacteria and an ancestral host cell ingested some of these aerobic bacteria. Some of these bacteria remained and continued to perform respiration within the host cell.

  • why aerobic?: Mitochondria burn oxygen and provide energy for the body, therefore the ancestral cells which were supposedly external to the eukaryotic cell, must be aerobic.
122
Q

Explain ”endosymbiosis” on the origin of chloroplasts

A

Hypothesis: The ancestors were photosynthetic bacteria that lived inside a large host cell. Instead of being digested, some remained and continued to perform photosynthesis
- mitochondria evolved first before chloroplasts

123
Q

Outline the structural evidence that supports the endosymbiosis theory [5]

A

1.) Structural evidence:

  • Mitochondria and chloroplasts have the same size and shape as prokaryotic cells;
  • They both have a double membrane — implies that they had their own membrane before being engulfed by the eukaryotes;
  • also had 70s ribosomes when eukaryotes had 80s ribosomes.;
  • have circular naked DNA like that of prokaryotic cells;
  • common genetic sequences* with prokaryotes;
124
Q

Outline the functional/behavioral evidence of enodymbiosis

A

both mitochondria and chloroplasts:

  • move independently within the eukaryotic cell (seem that they had their own life, an organism)
  • reproduce independently of the host cell through a process similar to *binary fission
  • inhibited by probiotics like prokaryotes
125
Q

Define genome(s). Explain how they are seen in the organisms

A

The genetic information of an organism
- ALL cells within an organism share a genome.

126
Q

Explain why genomes are called “housekeeping genes”

A

They are code for proteins that are associated with the basic cellular functions
- includes cell cycle regulation, DNA replication and metabolism

(ahh so it’s like if the proteins are the computers, the genomes are the programs, because of their genes they’re inclined to do their cellular processes)

127
Q

Outline the reason why, even with the same genomes, there are cells which have dissimilar/specialized shapes and functions?

A

Differentiation
- development of specialized structures and functions of cells

128
Q

Explain how differentiation occurs

A
  • Occurs: when different cell types express different genes.

Example:

129
Q

For genes that are not genomes of a certain thing, what is the implication on their gene expression?

A

Some cell types express the gene whereas other cell types don’t

130
Q

Outline how are stem cells able to specialize?

A

They turn off some genes (aka do not express them) and express others

131
Q

Outline (the two ways) how environmental conditions can change gene expression.

A

The expression of genes in an organism can be influenced by the enviornment:

1.) External world
- where the organism is located and develops
- e.g.: drugs, chemicals, temperature, light
- for instabce: protein provides coloration on the skin and hair/fur is called melanin.

2.) Internal world
- includes its hormones and metabolism

132
Q

Define tissues

A

Group of cells that have differentiated in the same way to perform the same function

133
Q

Outline the benefits of cell specialization (ASK QUESTION)

A

It is more efficient because:
- cells can focus on fewer tasks at once to conserve energy
- they evolve to doing those tasks better
- can have specialized structures and metabolism
- wdym by specialized metabolism

134
Q

When was the evidence of multicellularity?

A

2500 million or billion (?) years ago

135
Q

Define the concept of “multicellularity” and give examples

A

Organisms composed of more than 1 cell

  • all animals
  • all plants
  • most, but not all, fungi
  • what are the exceptions?
  • many but not all algae
  • exceptions?
136
Q

Explain the evolution of multicellularity

A

**Evolved independently many times in eukaryotes **
Steps:
1.) Formation of clusters from single cells
2.) Differentiation of cells within cluster for specialized functions
- (e.g. tissues?)

137
Q

Outline two hypotheses for how cells may have formed clusters in the evolution of multicellularity

A

1.) A group of independent cells come together

2.) When a unicellular organism divides, the daughter cells fail to separate, causing in an aggregate of identical cells

138
Q

Give the characteristics of clusters

A
  • selective advantage over independent cells
  • begins to serve specialized functions
139
Q

Define and explain “biofilms”

A

a thin, slimy film of bacteria

(biofilm dispersion happens when the cells do not produce the glue needed for holding the biofilm (and thus the bacteria jelly that holds all of the, tgt)

140
Q

Give the formula to get the FOV diameter in HP

A
141
Q

Give the two methods of estimating the size of the specimen in the microscope field of view

A
142
Q

Explain exocytosis

A

Definition: The release of cell contents from the cell to the outside

Process: The vesicles “bud”/“fuse” with the plasma membrane to release the contents of the vesicles.

143
Q

Explain ATP.

A

Adenosine triphosphate (ATP) is the source of energy (bc of its high energy) for use and storage at the cellular level.
- mitochondria produces ATP but not energy
- energy currency

144
Q

Explain turgor pressure

A

Liquid has a pressure. When a cell stores liquid such as water the pressure of the water will push out the cell.
- Therefore, for the plant cell and the fungi cell, they need a cell wall to reinforce their shape (counter-pressure?)

145
Q

Explain infolding

A
146
Q

Describe the DNA in nucleoid

A

Naked (uncoiles) and linear