Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Core Principles Eduqas Biology A Level > Cells > Flashcards

Cells Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

Give a brief description of cells

A

Cells are the basic unit of all living things and they contain many specialised organelles each of which carry out a particular function.

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

Nucleus

A

The nucleus contains the nucleolus and and is surrounded by the nuclear envelope which has nuclear pores in. It contains DNA which codes for protein synthesis

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

Nucleolus

A

Carries out the synthesis of r RNA and ribosomes

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

Nuclear pore

A

Allows transport of mrna out of the nucleus

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

Nuclear envelope

A

Separates the DNA from the cytoplasm

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Cell membrane

A

Uses selective permeability to control substances entering and leaving the cell

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

Cytoplasm

A

Site of chemical reactions within the cell

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

Mitochondria purpose

A

Contains DNA and ribosomes, site of aerobic respiration ands the synthesis of ATP.

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

Mitochondria structure

A

Mitochondria have two membranes that are separated by a narrow fluid-filled intermembrane space. They are 1 to 10 micrometres in diameter. The inner membrane is is folded to create a greater surface area. The folds in the membrane are called cristae and this is where part of the respiratory process takes place. The interior matrix contains enzymes.

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

Rough endoplasmic reticulum RE r

A

Transport proteins synthesized by attached ribosomes. The re r is a system of flattened sacs (cisternae) continuous with the nuclear membrane and sometimes linking to the Golgi apparatus

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

Smooth endoplasmic reticulum s e r

A

The synthesis and transport of lipids. It forms a system of flattened sacs (cisternae) , is continuous with the nuclear membrane and is sometimes linked to the Golgi apparatus. It has no ribosomes unlike the rough endoplasmic reticulum

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

Golgi body / apparatus

A

It is similar to the endoplasmic reticulum but more compact and surrounded by vesicles. It chemically modified proteins, produces lysosomes, produces glycoproteins and packages proteins for secretion out of cell.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Centrioles

A

Used in spindle formation – microtubules - in Cell division. They are 2 hollow cylinders that are perpendicular to one another.

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

Ribosomes

A

Synthesise proteins. They are are two subunits made from r r n a ( ribosomal ) and protein. There is one large subunit and one small.

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

Lysosome

A

1 micrometer diameter. They are small vacuoles formed when small portions of Golgi body are pinched off. They contain and isolate digestive enzymes. They can release and destroy organelles. They manage the digestion full of material taken in to cell for example white blood cells engulf bacteria by phagocytosis and then lysosomes are used in the digestion of that bacterium

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

Vesicles in plants - large permanent vacuole

A

large membrane-bound organelles surrounded by a tonoplast (membrane). They store ions and organic molecules for example proteins and they maintain osmotic pressure

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

Vesicles in animals

A

They are small membrane bound organelles. They act as a contractile vacuole to maintain osmotic pressure.

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

Chloroplast structure

A

They are 2 to 10 micrometres in diameter and 1 micrometres thick. They have a double membrane. In chloroplasts there is a fluid called Stroma which contains ribosomes , lipids, circular DNA and starch granules . There are stacks called granum in chloroplasts. These stacks are of flattened sacs called thylakoids. They contain photosynthesis pigments such as chlorophyll. between the thylakoid form lamellae…?

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

Chloroplast function

A

They are the site of photosynthesis

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

Cell wall

A

Provides strength and support and is freely permeable to water . it is made of cellulose microfibrils in a polysaccharide Matrix

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

Plasmodesmata

A

These are seen between two plant cells. It is a narrow thread of cytoplasm that passes through cell walls of adjacent plant cells. They allow the exchange of large organic materials via cytoplasmic streaming. They allow communication between adjacent cells.

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

What organelles are present only in animal cells?

A

Lysosomes and centrioles

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

What organelles are present only in plant cells?

A

Large permanent vacuole, chloroplast, cell wall , plasmodesmata and smooth endoplasmic reticulum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

What are prokaryotes

A

They include bacteria and were the first living thing on the planet.

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

What are the similarities of prokaryotes and eukaryotes?

A

They share ribosomes, cytoplasm, cell membrane and DNA

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

What are the differences of prokaryotes and eukaryotes?

A

Prokaryotes have 70s ribosomes and eukaryotes have 80s ribosomes. Prokaryotes have no membrane bound organelles. Prokaryotes don’t have a nucleus but eukaryotes do. The DNA in prokaryotes is circular, where is it is linear and bound to histo proteins in eukaryotes. The cell wall in prokaryotes is made of peptidoglycan but the cells are made from cellulose in plant cells, chitin in fungi and don’t exist in animal cells.

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

What do eukaryotes include?

A

Plant animal and fungus

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

What is magnification?

A

The number of times larger an image is compared with the real size of the object

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

magnification =

A

Size of image ÷ by actual size of specimen

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

magnification =

A

Size of image ÷ by actual size of specimen

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

What is a virus?

A

Genetic material encased in a protein capsid. It is non-cellular and cannot self replicate

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

What is a tissue

A

Groups or layers of similar cells working together to perform a specific function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Organ

A

A collection of different types of tissues working together to perform a specific function

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

What do plasma membranes do?

A

The control entry and exit of substances as they are selectively permeable. They have specialised roles depending on the location.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

Where can one find plasma membranes?

A

On the external of a cell in both prokaryotes and eukaryotes. Within cells in eukaryotes for their membrane-bound organelles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

What does it mean to be hydrophobic?

A

A substances nonpolar and nonionic, is soluble in organic solvents, likes other hydrophobic molecules, hate anything that is hydrophilic including water.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

What does it mean to be hydrophilic ?

A

Something likes water, is water soluble, is polar or charged, likes other hydrophilic molecules and hates anything that is hydrophobic. Hydrophilic substances are attracted to water and polar, ionic or charged substances.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

What are the 4 types of epithelium?

A

Ciliated columnar, cuboidal, squamous glandular

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

What are the three types of muscle?

A

Skeletal (striated), smooth , cardiac

40
Q

How quickly do epithelial cells divide?

A

Quickly

41
Q

Structure of squamous epithelium

A

cells are thin and smooth, cells are packed closely together and have a smooth lining to reduce friction. They have a basement membrane on the bottom

42
Q

Function of squamous epithelium

A

Allow gas exchange to take place as thin cells mean a short diffusion distance. They are lining tissue and cover the surface of organs cavities and tubes

43
Q

Locations of squamous epithelium

A

Alveoli and blood vessels

44
Q

Location of cuboidal epithelium cells

A

Small intestine, kidney tubules and other tubes, glandular ducts

45
Q

Location of of columnar epithelium tissue

A

Organs and tubers, small intestine ( microvilli)

46
Q

Location of ciliated epithelial tissue

A

Organs and tubules, trachea and bronchi

47
Q

Location of glandular epithelium tissue

A

Digestive system e.g. salivary glands

48
Q

Function of glandular epithelium

A

To contain mucous secreting goblet cells, secrete enzymes, hormones,, mucus

49
Q

Function of cuboidal epithelium cells

A

Involved in absorption or secretion

50
Q

Function of ciliated epithelium cells

A

To support cilia function. The cilia waft to move dust and dirt out of air passages and the

51
Q

Function of columnar without cilia epithelial cells

A

To support the microvilli as they increase surface area for absorption

52
Q

What is the structure of cuboidal epithelial cells

A

They are cube like box shaped cells with a prominent nucleus. They sit on a basement membrane.

53
Q

What is the structure of of columnar epithelial cells without cilia ?

A

They are column shaped and have microvilli and a basement membrane on the bottom

54
Q

What is the structure of ciliated epithelial cells?

A

The column shaped and have a basement membrane on the bottom and have cilia on the top

55
Q

What is the structure of glandular epithelial cells?

A

The secretory epithelial cells organised themselves into gland shapes. There are some columnar epithelial cells embedded amongst the epithelium tissue.

56
Q

Describe epithelial tissue in general

A

They are lining tissue and cover the surface of organs, cavities and tubes . the cells are packed closely together and rest on and basement membrane

57
Q

Describe muscle tissues in general

A

They can all contract to shorten their length, there are three types of muscle tissue , inside the cells are protein fibres made of actin and myosin which slide past each other to shorten the cell

58
Q

What is connective tissue made out of

A

Collagenous fibres and elastic fibres

59
Q

What is the structure of connective tissue

A

All the connective tissues except for blood contain the protein collagen in the extracellular material

60
Q

What’s the function of connective tissue

A

Connects other tissues together and supports the body

61
Q

where can connective tissue be found in the body

A

Everywhere for example blood bone cartilage. These are all forms of specialised connective tissue

62
Q

What is the structure of skeletal muscle

A

Muscle cells are joined together to form fibres. The striations ( Stripes) are caused by overlapping protein molecules in the cells

63
Q

What is the function of skeletal muscle

A

These muscles are used to move whole organisms or parts of them. For example skeletal movement, moving bones, maintaining posture and other body positions, supporting soft tissues.

64
Q

Where are skeletal muscles located in the body

A

They are attached to bones by tendons

65
Q

What is the structure of Smooth muscles

A

They are unclstriated, individual cells which can shorten in length

66
Q

What is the function of Smooth muscle cells

A

They work automatically and are involved in many housekeeping functions of the body

67
Q

Location of Smooth muscle tissues in the body

A

In the walls of the intestine and blood vessels, Iris, gastrointestinal tract, bladder, walls of hollow organs EG stomach

68
Q

What is the structure of the cardiac muscle

A

Fibres are striated and branched. They are attached at the ends to adjoining fibres by thick plasma membranes called intercalated discs

69
Q

Function of cardiac muscle

A

Rhythmic contraction pump blood through the heart

70
Q

Location of cardiac muscle

A

Only in the heart

71
Q

What does the term endosymbiotic mean

A

Two or more or organisms are in a mutually beneficial relationship….?

72
Q

What prokaryotes came together to form cells as we know it

A

Engulfing bacteria, photosynthesising bacteria, respiring bacteria

73
Q

How did chloroplasts come into existence

A

Engulfing bacteria engulf the photosynthesising bacteria

74
Q

How did mitochondria come into existence

A

Engulfing bacteria engulfed respiring bacteria

75
Q

What is the evidence of how chloroplasts and mitochondria came into existence?

A

The ribosomes are all 70s and genes in the DNA are similar in prokaryotes and mitochondria and chloroplasts. All three are self-replicating. The inner membrane of chloroplasts is similar to photosynthetic cells. The inner membrane of mitochondria is similar to respiring cells. The outer membrane is similar in structure between mitochondria, chloroplasts and the engulfing cell.

76
Q

What is the structure of a glycoprotein?

A

Carbohydrate attached to a protein

77
Q

What are intrinsic proteins

A

Proteins that are embedded in the phospholipid bilayer and are present the whole way through

78
Q

What are extrinsic proteins

A

Proteins embedded in the phospholipid bilayer that are only in one layer of phospholipids

79
Q

how wide is the phospholipid bilayer

A

7 nanometres

80
Q

Are phosphate heads hydrophilic or hydrophobic?

A

Hydrophilic

81
Q

What is the structure of a glycolipid

A

A polysaccharide attached to a phospholipid

82
Q

What are the two types of intrinsic protein?

A

Channel protein and carrier protein

83
Q

Describe the structure of cholesterol in the phospholipid bilayer

A

They are the smallest constituent and are embedded between fatty acid tails….?

84
Q

Are fatty acid tails hydrophobic or hydrophilic?

A

Hydrophobic

85
Q

What structure do intrinsic proteins have?

A

Tertiary structure 3D globular…..?

86
Q

Describe chemically a hydrophilic head and hydrophobic tail

A

The hydrophilic head has a glycerol molecule which is bonded to to a phosphate group. The glycerol molecule is then bonded to one saturated fatty acid and one unsaturated fatty acids which make up the hydrophobic tails.

87
Q

What are the roles of plasma membranes within cells

A

To separate cell components from cytoplasm in a process called compartmentalization. To hold components of metabolic pathways in place e.g. mitochondria

88
Q

What are the roles of plasma membranes on the surface of cells?

A

Two separate cell contents from the outside environment, for cell recognition and signalling, to regulate transport of materials into or out of cells

89
Q

What is the fluid mosaic model of a plasma membrane and why is it called that?

A

This model was suggested in 1972 to by singer and Nicolson. They stated that molecules are not bonded together so there is some movement but the membrane is relatively stable because of the nature of the phospholipid. It is called the fluid mosaic model because the phospholipids and proteins move around each other so they are fluid and and the arrangement of proteins within the phospholipid bilayer is like a mosaic.

90
Q

How can the fluidity of the plasma membrane be proved?

A

Proteins can be marked, a photo taken and then another photo taken having left the marked proteins. By this time the proteins will have move proving membrane is fluid.

91
Q

what is the function of the phosphate head?

A

To interact with the water external to the cell and in the cytoplasm.

92
Q

What is the function of the hydrophobic tail

A

To allow the passing through of hydrophobic substances

93
Q

What is the the purpose of intrinsic proteins?

A

To allow the passing through of hydrophilic substances.

94
Q

What is the purpose of the phospholipid bilayer

A

To selectively enable substances to pass in and out of the cell by being a selectively permeable membrane

95
Q

What does the term polar mean?

A

It means a molecule has inner charges resulting in a positive part and a negative part

96
Q

How is diffusion affected by an increasing concentration difference across the membrane?

A

The rate of diffusion will increase

97
Q

How is the rate of diffusion affected in facilitated diffusion as the concentration difference across the membrane is increased?

A

At first there is an increased rate of diffusion. It is faster than in simple diffusion because the proteins are specific to the molecules they are transporting. Then the rate of diffusion will no longer increase despite an increasing concentration gradient. This is because the channel carrier proteins act as limiting factors as they fully saturated at one time.

Core Principles Eduqas Biology A Level (8 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions