Cells Flashcards

You may prefer our related Brainscape-certified flashcards:
1
Q

Living organisms are classified into 3 domains:

A

Bacteria, Archaea and Eukarya

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Which domain(s) are pokaryotic?

A

Bacteria and archaea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Which domain(s) are eukaryotic?

A

Eukarya

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Characteristics of prokaryotes

(4)

A
  • single celled organisms
  • Lack membrane-bound organelles
  • DNA is not seperated from the cytoplasm in a nucleus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What can be said about bacteria

(2)

A

Bacteria are the most diverse and widespread prokaryotes and are now classified into multiple kingdoms.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What can be said about archaea?

A

Archaea live in Earth’s extreme environments, such as salty lakes and boiling hot springs.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Characteristics of eukarotes

(3)

A
  • contain membrane bound organells
  • more complex organisms
  • DNA in a nucleus - seperated from the cytoplasm by a membrane
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Domains of eukarya

(4)

A
  1. Plantae
  2. Fungi
  3. Animalia
  4. Protista
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

3 major characteristics of prokaryotic cells

(3)

A
  1. Within the cytoplasm, much less and/or smaller organelles or none
  2. Rigid cell walls: surrounding the plasma membrane
  3. No membrane bound nucleus: the genetic material (DNA) is found in the nucleoid region
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Cytoplasm

A

the region between the nucleus and the membrane bounding the cell which consists of a semifluid medium called the cytosol, in which are found various organelles.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What can be said conserning the size of eukaryotic and prokaryotic cells?

A

Eukaryotic cells are generally much larger than prokaryotic cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Why are cells small

A

a smaller object has a greater ratio of surface area to volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Do larger organisms have larger cells than smaller organisms? Explain

A

No, they do not. They simply have more cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Example of a cell where a high ratio of surface area to volume is important

A

Intestinal cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is one way to increase surface area without a big increase in volume?

A

Microvilla - long projections on cells surfaces

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Key roles of the cell membrane

(5)

A
  1. Controlling cell function
  2. cell adhesion
  3. recognition and communication
  4. keeping its molecules of life from dissipating away
  5. keep out foreign molecules that damage or destroy the cells components and molecules
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

The plasma membrane and the various internal membranes of cells consist of a _______ of ________ with _____________ attached to or imbedded in it.

A

The plasma membrane and the various internal membranes of cells consist of a double layer of phospholipids with proteins attached to or imbedded in it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is found along the membrane apart from phospholipids?

A

Proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Nucleus

A

Contains DNA and controls cellular activity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Nucleolus

A

A region where components of ribosomes are synthesized and assembled

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What happens after ribosomes are asesembled in the nucleolus?

A

They pass through the nuclear pores to the cytoplasm, where they combine to form ribosomes (the site of protein synthesis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

the DNA is organized along with proteins into a material called _______

A

the DNA is organized along with proteins into a material called chromatin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What happens to chromatin as a cell prepares to divide?

A

the stringy, entangled chromatin coils up (condenses) becoming thick enough to be discerned as separate structures called chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is a chromosome formed from?

A

A chromosome is formed from a single DNA molecule that contains many genes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Which organelles are apart of the endomembrane system? (7)

A

the nuclear membrane, the endoplasmic reticulum, the Golgi apparatus, lysosomes, vesicles, endosomes, and plasma membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Who am I?
So thin cannot be resolved under a light microscope

A

Endomembrane system

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Function of the endomembrane system

A
  • fills the cell + divides it into compartments
  • provides surfaces for protein and lipid synthesis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Endoplasmic reticulum (ER)

A

largest of the internal membranes
composed of a lipid bilayer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Two parts of the ER

A

Rough ER -studded with ribosomes involved in protein synthesis
Smooth ER- lacks ribosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

ER membrane weaves in sheets through the interior of the cell, creating a network of membranous tubules and sacs called _______

A

ER membrane weaves in sheets through the interior of the cell, creating a network of membranous tubules and sacs called cisternae

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

Cisternae

A

network of membranous tubules and sacs called within the ER

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

Smooth ER

(4)

A
  • lacks ER
  • Synthesizes lipids
  • Metabolises carbohydrates
  • detoxification of drugs and poisons
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

Rough ER

(3)

A
  • contains ribosomes
  • Ribosomes are the site of protein synthesis
  • When proteins are made for export the amino acids (building blocks of proteins) are threaded through the rough ER into it’s internal space.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Give an example of a specialized cells that secrete proteins produced by ribosomes attached to rough ER

A

Cells in the pancreas secrete insulin, a hormone, into the bloodstream

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Most secretory proteins are ________, proteins that are covalently bound to __________

A

Most secretory proteins are glycoproteins, proteins that are covalently bound to carbohydrates

32
Q

How do secretory proteins leave the ER

A

Secretory proteins leave the ER wrapped in the membranes of vesicles that bud like bubbles from the ER. Such vesicles in transit from one part of the cell to another are called transport vesicles.

33
Q

How does rough ER grow

A

rough ER grows in place by adding proteins and phospholipids to itself

34
Q

Golgi structure and explain the process

(4)

A
  • has a front and a back, with different membrane compositions
  • front end = cis face ; is located near the ER
  • vesicles fuse with the cis face, emptying their contents into the interior or lumen of the Golgi apparatus
  • ER-synthesized molecules then pass through the channels of the Golgi apparatus until they reach the back called the trans face, where they are discharged in secretory vesicles
35
Q

Golgi apparatus

A
  • functions in the collection, packaging and distribution of molecules synthesized in one place in the cell and used at another
  • Golgi modifies and sorts proteins prior to export
36
Q

Membrane bound organelles

(11)

A

Plasma membrane, cytoplasm, nucleus, ER, Golgi, vesicles, lysosomes, peroxisome, mitochondria, chloroplasts, vacuoles

37
Q

Non membrane bound organelles

(8)

A

Nucleolus, ribosomes, cytoskeleton, centrosome, cilia, flagella, cell wall, extracellular matrix

38
Q

Lysosomes

A

membrane-bound sac of hydrolytic enzymes that an animal cell uses to digest macromolecules

39
Q

What cen lysosomes hydrolyze?

A

nucleotides, proteins, lipids, phospholipids–all the major classes of macromolecules

40
Q

How do lysosomes arise

A

The lysosomes arise from budding from the trans face of the Golgi apparatus

41
Q

Peroxisome

A
  • The peroxisome is a specialized metabolic compartment bounded by a single membrane
  • Contain enzymes that remove H atoms from various substrates and transfer them to O2
42
Q

Peroxisome function

A

break fatty acids down into smaller molecules that are transported to mitochondria and used as fuel

43
Q

Peroxisomes in the liver

A

peroxisomes in the liver detoxify alcohol and other harmful compounds by transferring hydrogen from the poisons to O2

44
Q

Mitochondria

A

Mitochondria are the cells’ power sources and are found in nearly all eukaryotic cells
Cellular respiration: Chemical energy in food (ex glucose) converted → ATP

45
Q

Chloroplast

A
  • Phosynthesis - production of glucose
  • Contains a green pigment - chlorophyll
46
Q

Chloroplast

they grow and occasionally ____________ reproducing themselves

A

they grow and occasionally pinch in two, reproducing themselves

47
Q

Like mitochondria chloroplast are surrounded by a __________

A

Like mitochondria chloroplast are surrounded by a double membrane

48
Q

Origin of Mitochondria and Chloroplasts, name

A

Serial Endosymbiosis

49
Q

Serial Endosymbiosis

A

mitochondria and chloroplasts, originated from the engulfing, incorporation and then coevolution of smaller prokaryotic organisms into the larger eukaryotic cell

50
Q

Symbiosis

A

Two different species living in direct contact with each other. In this case, the two partners became mutually beneficial.

51
Q

Endosymbiosis

A

Symbiotic relationship in which the smaller species live inside the larger species

52
Q

Vacuoles (what and function)

A
  • large vesicles derived from ER and Golgi apparatus
  • perform a variety of functions in different cells
53
Q

In plants, smaller vacuoles can hold reserves _____________ such as the proteins stockpiled in the storage cells in seeds

A

In plants, smaller vacuoles can hold reserves of important organic compounds, such as the proteins stockpiled in the storage cells in seeds

54
Q

Vacuoles may also help protect the plant against herbivores by ___________

A

Vacuoles may also help protect the plant against herbivores by storing compounds that are poisonous or unpalatable to animals

55
Q

Some plant vacuoles contain _____

A

Some plant vacuoles contain pigments

56
Q

Central Vacuole

(2)

A
  • The main function: to maintain turgor pressure in the cell
  • Turgor pressure is the pressure of the cell’s contents pushing against the cell wall; it is only found in cells that have cell walls, such as those of plants, fungi, and bacteria
57
Q

Central vacules - how they come to be and what it contains

A
  • Mature plant cells generally contain a large central vacuole which develops by the merging of smaller vacuoles
  • The solution inside the central vacuole, called cell sap, is the plant cell’s main store of inorganic ions
58
Q

The central vacuole can be up to what percentage of the plant cell volume

A

The central vacuole can be up to 90% of the plant cell volume.

59
Q

What happends if the vacuole is not filled

A

If the vacuole is not filled the plants wilt

60
Q

Where are ribosomes found

A

ribosomes are found free in the cytosol

61
Q

Cytoskeleton - what is it

A

network of fibers extending throughout the cytoplasm

61
Q
A
62
Q

The three molecular structures of the cytoskeleton

A
  1. microtubules
  2. microfilaments
  3. intermediate filaments
63
Q

Cytoskeleton - function

(2)

A
  • To give mechanical support to the cell
  • To maintain its shape (especially important for animal cells, which lack walls)
64
Q

Microtubules

(4)

A
  • thickest of the 3 types of fibers
  • hollow rods of protein called tubulin which is a dimer, a molecule made up of two subunits
  • Microtubules shape and support the cell and also serve as tracks along which organelles equipped with motor proteins can move
65
Q

Who am I

  • involved in the separation of chromosomes during cell division
  • Found in flagella and cilia
A

Microtubules

66
Q

Centrosome

A
  • microtubules grow out from a centrosome
67
Q

Where are centrosomes located

A

located near the nucleus

68
Q

Who am I?

considered a “microtubule-organizing center”

A

Centrosome

69
Q

Where are centrioles found

A

a pair of centrioles is found within the centrosome

70
Q

What is responsible for the beating of flagella and cilia

A

specialized arrangement of microtubules

71
Q

Flagella characteristics

A

longer and there is usually only one per cell

72
Q

Motile cilia usually occur in ______ numbers on the cell surface

A

Motile cilia usually occur in large numbers on the cell surface.

73
Q

Flagella and cilia beating patterns

A
  • Flagella: undulating motion that generates force in the same direction as the flagellum’s axis
  • Cillia: alternating power and recovery strokes generating force in a direction perpendicular to the cilium’s axis
74
Q

Found in plant cells not in animal cells

(3)

A
  • Cell wall
  • Central vacoule
  • Chloroplast
75
Q

Found in animal cells not plant cells

(2)

A
  • Centrosome
  • Lysosome
76
Q

Cell Wall of Plants - functions

(4)

A
  • Protects the cell
  • Maintains its shape
  • Prevents excessive uptake of water
  • Hold the plant up against the force of gravity
77
Q

Whats thicker? Plant cell walls or plasma membrane?

A

Plant cell walls

78
Q

What are plant cell walls made up of?

A

the polysaccharide cellulose

79
Q

What are membrane proteins attacted to

A

The cytoskeleton

80
Q
A