Bio 120_midterm

studied byStudied by 1 person
0.0(0)
get a hint
hint

What is the goal of the cell cycle/ life cycle?

1 / 199

encourage image

There's no tags or description

Looks like no one added any tags here yet for you.

200 Terms

1

What is the goal of the cell cycle/ life cycle?

For the cell to divide into two daughter cells

New cards
2

What are the four processes of cell cycle?

  • Cell growth

  • DNA replication

  • Chromosomes in daughter cells

  • cell division

New cards
3

What is the biggest part of the cell cycle for bacteria?

Cell growth and DNA replication

New cards
4

How does the cell cycle in prokaryotic organisms happen?

The chromosomes are distributed through binary fission?

New cards
5

What are the three phases of bacterial cell cycle?

  • B period: end of cell division to DNA replication

  • C period: the time the chromosomes assemble

  • D period: time after chromosome replication and end of cell cycle

<ul><li><p>B period: end of cell division to DNA replication</p></li><li><p>C period: the time the chromosomes assemble</p></li><li><p>D period: time after chromosome replication and end of cell cycle</p></li></ul>
New cards
6

What is the process by which eukaryotes split?

Mitosis( evolution of binary fission)

New cards
7

Which is the biggest phase of cell cycle in bacteria? B phase, C phase or D phase

C period

New cards
8

Where does bacterial chromosomal replication start? (a specific site)

A site called The origin of replication in the middle of a cell.

how they work: the replication start and go on opposite ends by catalysts. The origins go to different poles to pull chromosomes in app direction. The plasma membrane grows apart.

New cards
9

What are the four phases of mitosis ?

  • G1 phase(growth)

  • S phase(synthesis)

  • G2 phase( gap 2 or growth 2)

  • M phase ( mitosis and cytokinesis)

New cards
10

What is interphase?

End of mitosis all the way to the beginning of mitosis

New cards
11

what are chromosomes?

They are nuclear units of genetic information that are divided and distributed during mitosis

chroma = colour (describing their strong staining by particular dyes)

soma = body

New cards
12

What are chromatids?

The replication of the DNA chromatids

It represents two identical molecules sister chromatids

New cards
13

What is a chromatid?

A small portion of DNA composed of

New cards
14

How do we define the number of chromosomes in a species?

By ploidy number

Diploid(2n): humains have 23 pairs of chromosomes, 46 in total . Half from one type(mom) and other from dad. Called homologue pais

Haploid(1n): gametes. Only have one copy of chromosomes of the same type

New cards
15

What is the longest phase of the cell cycle for eukaryotic cells?

Interphase

New cards
16

What happens in the G1 phase?

Cell caries its functions, grows. prepares ribosomes and enzymes. The DNA is not duplicated yet

New cards
17

What happened in the S phase?

DNA replication and chromosome duplication

New cards
18

What happens in G2 phase?

Cell growth continues and prep for mitosis. The DNA has replicated already.

New cards
19

Describe G0 phase?

Also called quiescence. Its a rest phase where it stops dividing

New cards
20

What are the five stages of Mitosis?

  • Prophase

  • Prometaphase

  • Metaphase

  • Anaphase

  • Telophase

New cards
21
<p>What is this structure ( purple strings) ? What is its function ?</p>

What is this structure ( purple strings) ? What is its function ?

Spindle: It’s a structure of proteins and microtubules that forms during cell division that separates the sister chromatids

New cards
22
<p>What is this structure (yellow)? What is its function ?</p>

What is this structure (yellow)? What is its function ?

Centromere: region not an actual structure) in the middle of a chromosome where the spindles attach

New cards
23
<p>What is this structure (yellow)? What is its function ?</p>

What is this structure (yellow)? What is its function ?

Centrosome: organizes the microtubule cytoskeleton and positions organelles. It’s a pair of microtubules

New cards
24

What is the function of a kinetochore ?

Kinetochore: a large protein that connects chromosomes to the spindle fibers/microtubules. It is in the center of the chromosomes in the outside area.

Binds the centromere and chromosomes together

New cards
25

What is the structure of cleavage furrow? What is its function ?

It’s a contractile ring formed by microfilaments

New cards
26

What is the structure of cell plate? What is its function ?

It is made from cell wall and cell membrane components brought during telophase in plant cells.

New cards
27

What’s the different between animal cells and plant cells in cytokinesis

Animal cells:the cleavage furrow is a contractile ring formed by microfilaments

Plant cells: vesicles for a cell plate within the cell to form a cell plate. A new cell wall forms and THEN, the membrane separates the new daughter cells

New cards
28

What can be stored in plant cells vacuoles?

  • Plastids/ pigments

  • nutrients

  • water

New cards
29

What is the longest phase of the cell cycle?

Interphase

New cards
30

Explain supercoiling

  1. Histones: proteins in packs of four that DNA wraps around

  2. Nucleosomes: 4 histones units wrapped by DNA

  3. Chromatin: 8 nucleosomes

  4. Chromosomes: chromatids chilled together

New cards
31

What’s the structure of DNA?

Double stranded helix

New cards
32

What happens in prophase? CC,x2, ½,s

  • Chromosomes condense( become visible in microscope)

  • Chromosomes are doubled (after G2)

  • Centrosomes divide in two parts (go opp of cell)

  • Spindles form

New cards
33

What happens in prometaphase?

  • Nuclear envelope breaks down!

  • Microtubules form complete spindles

  • Microtubules attach to kinetochores

New cards
34

How do spindles form and connect to chromosomes?

Microtubules extend from the centriole to form the spindle apparatus

New cards
35

What happens in Metaphase?

  • Spindles are fully fledged

  • Metaphase=middle: chromosomes align in the middle of the cell

  • Sister chromatids are held by two opp forces: kinetochores out and cohesins(protein complex) in

New cards
36

What happens during Anaphase?

  • seperase proteins splits the sister chromatids

  • spindles (myosin) bring chromatids to opposite poles

New cards
37

What happens during Telophase?

  • Chromosomes decondense

  • A new nuclear envelope forms around chromosomes (we still only have one cell!!!)

  • The cytoplasm divides by furrowing

New cards
38

Which of the following is not part of mitosis?

  • Anaphase

  • Cytokinesis

  • Prometaphase

  • Telophase

  • Metaphase

  • Anaphase

  • Cytokinesis

  • Prometaphase

  • Telophase

  • Metaphase

New cards
39

How do bacteria undergo cell division?

A pilus (surface of bacteria) leaves its body and enters the other’s membrane containing some genetic material (horizontal gene transfer)

<p>A pilus (surface of bacteria) leaves its body and enters the other’s membrane containing some genetic material <mark data-color="red">(horizontal gene transfer)</mark></p>
New cards
40

Why would cells undergo cell division?

  1. For cell development

  2. Cell growth (natural)

  3. Repair of organism

  4. Need to compete external source

New cards
41

Microscopy

The use of microscopes to visualize and study small objects or organisms.

New cards
42

Magnification

The process of enlarging the apparent size of an object in microscopy.

New cards
43

Resolution

The ability to distinguish between two closely spaced objects in microscopy.

New cards
44

Cytosol

The fluid portion of the cytoplasm, excluding organelles.

New cards
45

Cytoplasm

The contents of a cell, including the cytosol and organelles.

New cards
46

Organelle

A specialized structure within a cell that performs specific functions.

New cards
47

Light microscopy

The use of visible light to magnify and observe specimens.

New cards
48

Electron microscopy

The use of a beam of electrons to magnify and observe specimens with higher resolution than light microscopy. This includes SEMs and TEMs

New cards
49

Antonie van Leeuwenhoek

A scientist who was one of the first people to observe microorganisms using a microscope of his own design, making important contributions to biology.

New cards
50

Magnification

The ratio of the object as viewed to its real size.

New cards
51

Resolution

The minimum distance that two points in the specimen can be separated and still be seen as two points, depends primarily on the wavelength of light or electrons used to illuminate the specimen.

New cards
52

Light microscopes

Microscopes that use light to illuminate the specimen, including : bright field microscopy, fluorescence microscopy, and confocal microscopy.

New cards
53

TEM (Transmission Electron Microscopy)

A type of electron microscopy that involves rays transmitted through thin inTernal sections made using a microtome, with black objects on a white background.

New cards
54

SEM (Scanning Electron Microscopy)

A type of electron microscopy that involves rays scanned over the surface of a specimen

New cards
55

What are the two types of light microscopes?

  • Fluorescence Microscopy

  • Confocal Laser Scanning Microscopy

New cards
56

Explain Fluorescence Microscopy

A molecule in the specimen absorbs a particular wavelength of light and emits some of that light into another wavelength. Observed on a black back background.

Specific dyes used to label specific molecules

New cards
57

Explain Confocal Laser Scanning Microscopy

It focuses a laser light source onto a very thin plane. The specimens then emit a fluorescent light.

Used to examine thick specimens in 3D images

New cards
58

What is biology?

From the Greek —-Bios=life and logy=study.

New cards
59

What is an organism?

An assembly of molecules that function as a whole that exhibit life

Ex:

A tree absorbs sunlight through its leaves, converts it into energy through photosynthesis, and grows by producing new branches and leaves.

New cards
60

How many types of organisms are there? What are they?

Two:

  • Unicellular organisms

  • Multicellular organisms

New cards
61

What are the three postulates of Cell Theory?

  1. All organisms are composed of one or more cells

  2. The cell is the basic structural and functional unit of al living organisms

  3. Cells arise only from the division of pre-existing cells

New cards
62

Robert Hooke, 1665

English scientist who defined the term "cell" and made significant contributions to the field of microscopy.

New cards
63

What is essential to life?

Energy

• For living cells, energy is required to build complexe things (proteins)

New cards
64

Why was the invention of the microscope crucial to biology?

Allowed scientist to understand how living organisms were built from cells

New cards
65

What are the different cell types?

  • Prokaryotic cells

  • Eukaryotic cells

New cards
66

What is a prokaryotic cell?

A cell with no nucleus

New cards
67

Name features of a prokaryotic cell

  • No nucleus (NUCLEOID)

  • No organelles

  • Small (micrometer)

  • Hopanoids

  • Usually spherical,rodlike and spiral

<ul><li><p>No nucleus (NUCLEOID)</p></li><li><p>No organelles</p></li><li><p>Small (micrometer)</p></li><li><p>Hopanoids</p></li><li><p>Usually spherical,rodlike and spiral</p><p></p><p></p></li></ul>
New cards
68

What is an eukaryotic cell

A cell with a nucleus ( central space with all the DNA)

New cards
69

Name features of an eukaryotic cell

  • Has a nucleus

  • Has specific organelles that carry out basic fns of life

  • Large (10-20 micrometers)

  • Sterols

<ul><li><p>Has a nucleus</p></li><li><p>Has specific organelles that carry out basic fns of life</p></li><li><p>Large (10-20 micrometers)</p></li><li><p>Sterols</p></li></ul>
New cards
70

What is COGRASHE?

  • C-made up of one ore more cells

  • O- displays organisation

  • G- grows and develops

  • R- reproduces

  • A- adapts

  • S- responds to stimuli

  • H- homeostasis

  • E- requires energy

New cards
71
New cards
72

What are the four essential elements to all living cells?

  • Plasma membrane

  • Cytoplasm

  • Chromosomes

  • Ribosomes

New cards
73

What is the structure of the plasma membrane?

It is made of a bilayer of phospholipid molecules.

The molecule contains:

  • a hydrophilic head( polar )

  • a hydrophobic tail(non-polar)unsaturated+ saturated

<p>It is made of a bilayer of phospholipid molecules.</p><p>The molecule contains:</p><ul><li><p>a hydrophilic head( polar )</p></li><li><p>a hydrophobic tail(non-polar)unsaturated+ saturated</p></li></ul>
New cards
74

What is the function of the plasma membrane?

It controls the flow of substances of the cell. That is essential for maintaining the internal environment.

New cards
75

Where and what does the cytoplasm do?

It’s below the plasma membrane within the cell. It is a fluid that cates and environment for cell processes.

New cards
76

What is the cytosol?

It’s the aqueous part of the cytoplasm where DNA synthesis

New cards
77

What is the cytoskeleton?

It’s a network of fibers throughout the cytoplasm

  • maintain the cell’s shape

  • organize cell’s activity and structure

  • fixes many organelles

  • chromosome segregation during cell division

New cards
78

Which domains consists of prokaryotic cells?

  • Bacteria

  • Archaea/mue bacteria

New cards
79

Which kingdoms make up the domain eukariya?

  • Animals

  • Plants

  • Fungi

  • Protista

New cards
80

Bacteria and archaea are ____________ distinct.

Bacteria and archaea are evolutionary distinct

New cards
81

What are some structural organelles present in plant cells but not animal cells?

  • Chloroplasts

  • Central vacuole

  • Cell wall

  • Plasmodesmata

New cards
82

What is the definition of an organelle?

A structure surrounded by a membrane

New cards
83

Describe the structure of a prokaryotic cell

  • Rigid cell wall (capsule) made of gycocalyx

  • Plasma membrane

  • Use flagella or pills for locomotion

<ul><li><p>Rigid cell wall (capsule) made of gycocalyx</p></li><li><p>Plasma membrane</p></li><li><p>Use flagella or pills for locomotion</p><p></p><p></p></li></ul>
New cards
84

How do bacterial plasmids differ in comparison to other organelles?

They contain an extrachromosomal DNA that replicate independently

New cards
85

What does the plasma membrane do in prokaryotic cells?

  • Metabolizes food into energy ( mitochondria in eukaryotes)

New cards
86

What does the cell wall do in prokaryotic cells?

It covers and hides the cell from external organisms

New cards
87

What does the mitochondria do in eukaryotic cells?

Site for cellular respiration/energy production

IT IS AN INDEPENDANT ORGANELLE FROM THE CELL

New cards
88

What are some structural organelles present in animal cells but not plant cells?

  • Lysosomes

  • Centrioles

  • *Flagella

New cards
89
<p>Label the following structures on the drawing:</p><ul><li><p>Nuclear envelope</p></li><li><p>Nuclear pores </p></li><li><p>Nucleolus</p></li><li><p>Chromatin</p></li><li><p>Rough ER</p></li><li><p>Ribosomes</p><p></p></li></ul>

Label the following structures on the drawing:

  • Nuclear envelope

  • Nuclear pores

  • Nucleolus

  • Chromatin

  • Rough ER

  • Ribosomes

knowt flashcard image
New cards
90

What is the nuclear envelope?

It encompasses the nucleus region and made up of two lipid bilayers

New cards
91

What are the nuclear pores?

It’s perforation through the nuclear envelope forming channels that regulate the transport of molecules between nucleus and cytoplasm

New cards
92

What is the nucleolus?

Distinct middle area of the nucleus that assembles ribosomes

New cards
93

What is the nuclear lamina?

It’s a dense fibre network of intermediate filaments

New cards
94

Where is a particularity of the ribosomes?

They are not considered an organelle

New cards
95

What are ribosomes made up of?What is their structure?

  • rRNA + proteins

  • They have two subunits:Large subunit (top) and small (bottom)

<ul><li><p>rRNA + proteins</p></li><li><p>They have two subunits:Large subunit (top) and small (bottom)</p></li></ul>
New cards
96

What is the role of ribosomes?

The site for protein synthesis: by decoding mRNA and forming polypeptide chains

New cards
97

Where are the ribosomes located?

  • Outside the Rough ER/ on nuclear envelope (bound)

  • In the cytosol (free)

New cards
98

Where is the site of photosynthesis in plant cells?

Chloroplast: use solar energy to produce food (sugar)

New cards
99

What are peroxisomes?

They are organelles (single membrane) which produce H2O2 to change into H2O. Oxidizes it

New cards
100

What are the two membranes called in the mitochondria?

  • Smooth outer membrane

  • Inner membrane (cristae) looks like folds

New cards

Explore top notes

note Note
studied byStudied by 7 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 19 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 11 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 15 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 11 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 9 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 16 people
Updated ... ago
5.0 Stars(1)
note Note
studied byStudied by 7884 people
Updated ... ago
4.8 Stars(53)

Explore top flashcards

flashcards Flashcard35 terms
studied byStudied by 1 person
Updated ... ago
5.0 Stars(1)
flashcards Flashcard39 terms
studied byStudied by 9 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard46 terms
studied byStudied by 21 people
Updated ... ago
5.0 Stars(2)
flashcards Flashcard227 terms
studied byStudied by 81 people
Updated ... ago
5.0 Stars(2)
flashcards Flashcard50 terms
studied byStudied by 6 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard113 terms
studied byStudied by 66 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard27 terms
studied byStudied by 4 people
Updated ... ago
5.0 Stars(1)
flashcards Flashcard21 terms
studied byStudied by 1189 people
Updated ... ago
5.0 Stars(4)