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Flashcards in Cell Biology Deck (79):
1

What is cell biology also known as?

Cytology

2

A cell is the most basic working unit of _______

life

3

New cells only arise how?

From existing cells, by cell division

4

What are the two basic types of microscopy?

Light microscopy, electron microscopy

5

What type of microscopy is dependent on on transmitted light to illuminate the biological sample of interest?

Light microscopy

6

What type of light microscopy is the conventional form of light microscopy, using visible light as the source?

Brightfield microscopy

7

Which type of microscopy depends on ultraviolet light to illuminate the specimen against a black background?

Fluorescence microscopy

8

What type of microscopy depends on an electron beam to bombard the specimen (which has normally been killed by chemical fixation prior to examination)?

Electron microscopy

9

What is the key advantage of electron microscopy over light microscopy?

A greater resolution (by at least 100x)

10

When an electron beam passes through an ultrathin, carefully prepared section of the specimen to reveal the contents of the cell which is "stained" with heavy metal it is __________

Transmission Electron Microscopy (TEM)

11

When a specimen remains intact, but gets coated with a thin film of heavy metal so that the beam is deflected off the contoured surface to yield a 3-d image it's called __________

Scanning Electron Microscopy (SEM)

12

What separates the cytoplasm of the cell from the cell exterior?

the cell (plasma) membrane

13

What accumulates as a protective matrix along the membrane's outer surface?

Biomolecules

14

The cytoskeleton in made of microfilaments of a protein called _____

Actin

15

Complexity, ex. possession of more types of organelles, is more common in _____ ____

eukaryotic cells

16

Which cells have no membrane bound nucleus?

Prokaryotic

17

Which cells are small and unicellular or occasionally colonial? (NEVER multicellular)

Prokaryotic cells

18

What is composed of a phospholipid bilayer with other components like protein channels that governs entry and exit of materials in the cell?

The cell membrane

19

The cell membrane represents the major, and usually only, membrane system of a ________ cell.

Prokaryotic

20

What does the cytoplasm of a prokaryotic cell contain?

a nucleoid region (DNA), and ribosomes

21

Prokaryotic cells rarely possess a vacuole lined by a membrane called ______

the tonoplast

22

Tonoplasts help to retain ___ _______

cell turgor

23

Prokaryotes also have external features like a cell wall, glycolayx, pili, and ________

flagella

24

The cell wall protects the cell membrane and _______

cytoplasm

25

What is secreted externally to the cell wall as a slime layer or capsule?

The glycocalyx

26

The glycocalyx enables the cell to adhere to substrates or to eachother (i.e. to form a ________)

colony

27

Short abundant extensions that assist in attachment to surfaces and even other cells are called ______

Pili (pilus singular)

28

What part of the cell is used for locomotion and possess proteins called microtubules which permit a flexible whip-like action?

Flagella (singular flagellum)

29

Which cells can be singular, colonial, or commonly multi-cellular?

Eukaryotic cells

30

Eukarya contains what four groups?

Fungi, Animalia, Plantae, Protista (often unicellular)

31

Eukaryotes all have what?

A membrane bound nucleus

32

What is typically the largest organelle in a eukaryotic cell representing 10-20% of it's volume?

The nucleus

33

Two phospholipd bilayers, an inner and outer, which enclose a perinuclear space surrounding the nulceus of a eukaryotic cell comprise the _________

Nuclear envelope

34

What is the semi-fluid substance filled with chromatin inside the nucleus?

Nucleoplasm

35

What stores, protects, organizes, and expresses most of the cell's hereditary information?

The Nucleus

36

Each nucleus may have one or more _________

nucleoli

37

What consists of two subunits of rRNA and proteins?

Ribosomes

38

Inside the cytoplasm, is the ___________ system.

endomembrane

39

What includes vacuoles, lysosomes, secretory vesicles, Golgi apparatus, endoplasmic reticulum, and even the cell membrane?

The endomembrane system

40

What has an extensive, membranous network of flattened cisternae which are narrow tubules that contain fluid in the lumen?

The Endoplasmic reticulum

41

The rough endoplasmic reticulum is characterized by ________ attached to the cisterna's outer surface.

ribosomes

42

What happens in the smooth ER?

synthesis of lipids and production of hormones.

43

The synthesis of glycoproteins by adding a carbohydrate is called _________

glycosylation

44

What happens in the rough ER?

Glycosylation and formation and sorting of proteins

45

What serves as distribution centre for proteins?

Golgi complex

46

When a secretory vesicle fuses with the plasma membrane, releasing the vesicle contents to the cell exterior it is called ___________

Exocytosis

47

The golgi complex can perform what three functions?

glycosylation, protein sorting, and secretion

48

If materials from outside the cell were incorporated into the vesicles it would be called __________

endocytosis

49

Pinocytosis is when cells "sample" solutes in the external environment that ______ nutrients

absorb

50

Lysosomes are membrane-bound organelles of _________ cells

animal

51

Lysosomes contain hydrolases which function optimally in their ____ environment

acidic

52

A defective organelle in the cytoplasm will become surrounded by a membrane and form an _________

autophagosome

53

an autophagosome will fuse with lysosomes and they will convert it to subunits for ________

recycling

54

When the vesicle with cargo pinches off from the cell membrane and enters the cell's cytoplasm where this endocytotic vesicle fuses with a lysosome and the cargo is broken down into simpler compounds which are released to the cytoplasm it is called ____________

endocytosis

55

What is it called when a large membrane-bound vesicle surrounds and engulfs a fairly large item (ex. bacterium), proceeds to fuse with lysosome whose acid hydrolases dismantle the bacterial cell?

Phagocytosis

56

A fluid-filled sac is called a _______

vacuole

57

What is the single membrane that lines the vacuole?

The tonoplast

58

What type of vacuoles are present in many plant cells and take up much of the volume?

Central vacuoles

59

A central vacuole provides what two things?

Storage, Turgor pressure

60

What type of vacuole is present in many protists, gradually increasing in volume and eventually expelling its aqueous contents?

Contractile vacuole

61

Food vacuoles have food for eventual _______

digestion

62

Cytoskeleton maintains cell's ______ and organelle _______, even a cell's own motility.

shape, movement

63

What size is the diameter of microfilaments?

5-7 nm

64

Diameter of intermediate filaments?

8-12 nm

65

Diameter of microtubules?

25nm

66

Microfilaments are assembled from what protein?

Actin

67

What are the functions of microfilaments?

Muscle contraction, movement of pseudopods, separation of cytoplasm during cell division, cytoplasmic streaming

68

Intermediate filaments only occur in _________ organisms

multicellular

69

Microtubules are a major part of what apparatus at cell division?

Spindle apparatus

70

Which motor proteins have intimate association with cytoskeleton?

dyneins, kinesins

71

What is short but numerous and produces beating movements leading to locomotion or circulation of fluids and debris over the cell surface?

Cilia (cilium)

72

Mitochondria and plastids are both what?

Semi-autonomous organelles (have their own DNA)

73

Both mitochondria and plastids have a _______ membrane

double

74

If it has a mitochondria, nucleus, nucleolus, and nuclear envelope, it is what type of cell?

Eukaryotic

75

What plastids have chlorophyll? Grana, And thylakoids in each granum surrounding a lumen?

Chloroplasts

76

What plastids have pigment crystals?

Chromoplasts

77

Which plastids are starchy and colourless?

Leucoplasts (amyloplasts)

78

The semi-autonomous, energy-transforming organelles of eukaryotic cells, namely mitochondria and chloroplasts, may have descended from free-living prokaryotic cells is the Theory of what?

Endosymbiosis

79

Like prokaryotes, semi-autonomous organelles divide by __________ ________-.

Binary fission