Brainscape's Knowledge GenomeTM

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


See full index

Science 2024 > B1 > Flashcards

B1 Flashcards

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

Who and when first described cells

A

1665 Robert Hooke

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

Who and when was the first living cell absorbed

A

1674-1683 Anton van Leeuwenhoek first to observe bacteria and protoctista from pond water samples

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

Who and when was the first person to observe a nucleus

A

1831 and Robert Brown

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

Who created the universal theory?
What is it?
Who made it?

A

1839-Matthias Schleiden
All plant materials is composed of cells
The scientist credited for theory is Theodor Schwann-he proposed all living things composed of cells

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

Who and when was spontaneous generation disproved

A

1861-Louis Pasteur
He disproved as he demonstrated that bacteria will only grow in sterile nutrient broth after exposed to air

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

Who and when demonstrated evidence for the origin of new cells

A

1852-Robert Ramek observed cell division in animal cells-findings were not accepted at the time
Rudolf Virchow published the findings as his own to show new cells form from existing ones

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

When were light microscopes first developed

A

16th century

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

Limitations of light microscopy

A

Lower magnification and resolution compared to others
Maximum magnification of a light microscope is ×1500 +resolution is 200nm

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

Benefits of light microscope

A

Can observe sub-cellular structures/organelles e.g nucleus, mitochondria and chloroplasts

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

Resolution definition

A

The ability to distinguish between objects that are close together

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

How do electron microscopy work

A

Use a beam of electrons in a vacuum with a wavelength of less than 1nm to visualise specimen

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

Advantages of electronic miscroscopy

A

See more detail
Produce images called electron micrograph
Magnification of ×500,000
Higher resolution of 0.1nm
More stains can be used other than methylene blue which is only used for light microscopy

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

Magnification calculation

A

Size of image/actual image

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

How many nanometers is in a micrometre

A

1000

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

How many micrometers is in a millimetre

A

1000

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

How many millimetres is in a metre

A

1000

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

What is a prokaryotic cell

A

Single-celled organisms
Much smaller than eukaryotic
Bacteria cells
DNA is not contained in a nucleus

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

What is in a prokaryotic cell

A

Cell wall, capsule, ribosomes,nucleoid and plasmid

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

Cell wall structure and definition

A

Made of peptidoglycan +protects and supports cell

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

Capsule

A

Slippery layer outside cell wall of some species of bacteria+
Protects the cell and prevents dessication

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

Ribsomes

A

Smaller than ones in eukaryotic
Consist of two subunits and not surrounded by membrane

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

Nucleoid

A

Irregular shape that holds nuclear material without a nuclear membrane + holds genetic material
The Dna forms one circular chromosome
It is where genetic info can be found and controls cells activity

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

Plasmid

A

Small loops of DNA
They carry genes that benefit the survival of organism

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

Function of bacterial cells

A

Transcription proceess- RNA is formed (molecule with long chain of nucleotides) as it is paired with DNA containing a genetic code and when paired the hydrogen bond breaks

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

What is the practical for bacterial cells

A

Gram stain

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

What does gram stain identify

A

Bacteria that causes infections to enable them to decide most effective treatment

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

What r the two groups of bacteria gram stain can identify

A

Gram positive and negative

28
Q

How can they tell the difference between both groups

A

Have different cell wall structures and respond differently to antibiotics

29
Q

What happens during the staining technique

A

Bacterial smear is violet and safranin
Two stains are added to these bacterial
If there is a purple stain under the microscope it is positive
If there is a pink safranin stain then the bacteria is negative
As they have thinner walls and lipid membranes allow ethanol to wash off the purple stain and to retain the pink safranin stain

30
Q

What is a eukaryotic cell

A

Multi cellular organisms like plants or animals. Complex cells with a nucleus and membrane-bound organelles

31
Q

What is in an animal cell

A

Plasma membrane, cytoplasm, nucleus, nucleolus, rough ER, smooth ER, Golgi apparatus, vesicles, lysosomes , ribosomes,mitochondria and centrioles

32
Q

Plasma membrane structure and function

A

Composed of phospholipid bilayer, with proteins embedded in the layer
Permeable and regulates the transport of materials in and out of cell
Involved in cell signaling

33
Q

Cytoplasm

A

Thick, gelatinous, semi transparent fluid and maintains cell shape plus stores chemicals needed for the cell for metabolic reactions

34
Q

Nucleus

A

Largest organelle which has nuclear pores to allow movement of molecules through it
Nucleus contains chromatin
It controls and regulates cellular activity plus houses genetic material called chromatin, DNA and protein

35
Q

Nucleolus

A

Dense spherical structure in the middle of the nucleus
Makes RNA and ribsomes

36
Q

Rough ER

A

Network of membrane bound flattened sacs called cisternae studded with ribsomes
Protein synthesis takes place on ribsomes and newly synthesised proteins are transported to golgi apparatus

37
Q

Smooth Er

A

Network of membrane bound flattened sacs called cisternae studded with no ribsomes
Responsible for synthesis and transports lipids and carbohydrate
Involved in carbohydrate metabolism

38
Q

Golgi apparatus

A

A stack of membrane bound flattened sacs
Newly made proteins received from rough er
Modifies them and packages the proteins into vesicles to be transported where needed

39
Q

Vesicles

A

Small perusal membrane bound sacs with fluid inside
Used to transport materials inside the cell and secretory vesicles transport proteins to surface membrane

40
Q

Lysosome

A

Small spherical membrane bound sacs containing hydrolytic enzymes
Break down waste material including old organelles

41
Q

Ribosomes

A

Attached to rough er/free floating in cell
Consist of two sub units and are not surrounded by membrane
Protein synthesis occurs

42
Q

Mitochondria

A

Have two membranes
Inner membrane folded to form cristae and central is called the matrix
Can be seen as long in shape or spherical depending on the angle
Final stages of cellular respiration
Aerobic respiration lots of atp energy needed
Dna replication
Protein synthesis

43
Q

Centrioles

A

Small tubes I’d protein fibres and form spindle fibres during cell division

44
Q

Function of animal cell

A

Exocytosis which is the process of vesicles fusing with plasma membrane and secreting contents

45
Q

What is in a plant cell

A

All cellular components of an animal apart from centrioles.
Cell wall, chloroplast, vacuous, tonoplast, amyloplast, plasmodestmata, pits

46
Q

Cell wall plant

A

Made of cellulose
Protects and supports cell

47
Q

Chloroplast

A

Double membrane filled with fluid stroma
Inner membrane has flattened sacs called thylakoids. A stack of thylakoids is called a grana. Grana contains chlorophyll
Site of photosynthesis

48
Q

Vacuole

A

Membrane bound sacs in cytoplasm that contains cell sapphire
Maintains turgor to ensure rigid framework

49
Q

Tonoplast

A

Partially permeable membrane of vacuole
Allows small molecules through

50
Q

Amyloplast

A

Double membrane bound sacs containing starch
Responsible for synthesis and storage of starch

51
Q

Plasmodesmata

A

Microscopic channel which cross the cell wall of plant cells
Enables transport and communication between individual plant cells

52
Q

Pits

A

Pores in cell wall of cytoplasm
Allows water to enter and leave xylem vessels

53
Q

What is l dopa

A

Precursor for dopamine

54
Q

What does l dopa do

A

Increase dopamine stored in/released by presynaptic neuron

55
Q

What does increase of dopamine lead to

A

Normal levels of dopamine to stimulate postsynaptic neuron

56
Q

What does gram negative bacteria have

A

Two double pips membranes
S.g
Outer celle membrane/ a cell membrane that surrounds the cell wall

57
Q

Due to plaque building up in lumen what happens

A

Cells in artery wall in response

58
Q

How do vacuoles help photosynthesis

A

Push chloroplasts to edges
Store water
Short diffusion for carbon dioxide

59
Q

What’s on rough ers surface

A

Ribsomes

60
Q

What’s the difference between sperms and eggs nucleus

A

Sperms has half chromosomes than egg 23

61
Q

Qhat are myelinated axons and how do they impact conduction

A

Myelin sheath wrapped around axons which is made out of shwann cells, they are flattened and mainly called lipid membrane. Insulates the axon and prevents loss of ions. As ions can leave an enter the cell, nodes contains ion channels so impulse jumps from node to node so therefore faster transmission than when action potential occurs along the whole length

62
Q

Why are gram negative more resistant than positive

A

Because they have a larger impermeable cell wall

63
Q

What does penicillin do and for what bacteria

A

Antibiotics and only works on gram positive bacteria

64
Q

What is the bacteria responsible for mrsa and acn

A

Examples of positive bacteria whilst those responsible for Lyme disease and pneumonia are examples of gram negative

65
Q

Unicellular and multicellular definitions

A

Life forms consist of only one cell and life forms rhat are made of many cells

66
Q

What is 4um equivalent to 1mm

A

0.04mm

Science 2024 (10 decks)

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