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Flashcards in Unit 2 Deck (118):
1

What are classed as the smallest unit of life

Cells

2

What are cells

Building blocks of life

3

When can cells be seen

Only using a microscope as they are microscopic

4

What is the cells function

Cells of the same type work together to make tissues

5

What is the function of tissues

Work together to make an organ

6

What is organs function

Work together to make an organ system

7

What is systems function

Work together to make an entire organism

8

What is ment by unicellular

Organism made from only 1 cell

9

What is made from multicellular

Organism made from more than one cell

10

What does a animal cell contain

Nucleus
Ribosome
Cytoplasm
Cell membrane
Mitochondria

11

What is the structure of an animal cell

Blobbly

12

What is the structure of a plant cell

Well structured

13

What does a plant cell consist of

Vacuole
Ribosome
Cell wall
Cell membrane
Nucleus
Chloroplasts
Cytoplasm
Mitochondria

14

What is the function is nucleus

Contains DNA
Controls cells activities

15

What is the function of the cytoplasm

Where chemical reactions take place

16

What is the function of the cell membrane

Controls what enters and leaves the cell- selectively permeable
Transport across the membrane by osmosis , diffusion or active transport
Protects cell contents from environment

17

What is the function of the ribosome

Site of protein synthesis

18

What is the function of the cell wall

Made from chemical cellulose gives the cell support/ structure

19

What is the function of the vacuole

Regulates water concentration in the cell and supports for the cell

20

What is the function of the chloroplasts

Contain chlorophyll
Traps sunlight for photosynthesis

21

What is the function of the mitochondria/ ion

Site of respiration energy

22

What does the bacterial cell consist of

Flagellum
Cytoplasm
Cell membrane
Cell wall
Circular chromosome DNA
Ribosome
Plasmids

23

What does the bacterial cell wall consist off

Made from different substances

24

Function of the plasmid

Are DNA contains genes to make things

25

Function of the flagellum

Locemotion

26

What is diffusion

Passive movement
Particles in a liquid or gas move from a high area to area of low concentration
Down a concentration gradient
Until concentration is equal
Oxygen can enter cell by diffusion

27

What is osmosis

Special case of diffusion
Movement of water molecules from area of high water concentration to an area of low water concentration across a selectively permeable membrane
Passive process
Will happen until water concentration is equal on each side

28

What does the fungal cell consist of

Mitochondrian
Cytoplasm
Cell wall
Ribosome
Cell membrane
Nucleus

29

What is the cell membrane composed of

Phospholipids and proteins

30

How are the phospholipids arranged

In a bilayer

31

How are proteins arranged

In a bilayer with phospholipids

32

What do phospholipids do to the bilayer

Provide membrane with fluidity

33

What do proteins do for the bilayer

Structure and support and aid transport of substances across membrane

34

What happens in animal cell in dilute solutions

Burst(lysis)

35

Why do animal cells burst(Lysis)

As water moves into the cell until the cell membrane can not contain the contents

36

What happens with plants cells in dilute water

Turgid

37

Why do plant cells become turgid

Do not burst because cell wall prevents further uptake of water intake

38

What will happen to animal cell in a low water concentration

Shrink

39

What will happen to animal cells in solution with same water concentration

Normal

40

What will happen to plant cells in a concentrated solution

Plasmolysed

41

What will happen to plant cells in normal water concentration

Isotonic

42

Why do we calculate percentages

Start at different times , weight so it's fair

43

What is passive transport

Doesn't require energy
Osmosis and diffusion
Moves down a concentration gradient

44

What is active transport

Movement of substance from an are of low concentration to an are of high concentration
Against a concentration gradient

45

What does active transport require

Energy in the form of ATP
And is facilitated by carrier proteins in the cell membrane

46

What are chromosomes

Thread like structures composed of DNA that are found in the nucleus of all cells

47

What is the chromosome complement

Chromosomes contain genes and each species has a characteristic number of chromosomes

48

Explain diploid

All body cells contain 46 chromosomes

49

Explain haploid

Gametes contain 1 set of chromosomes 23 in total therefore gametes are called haploid cells

50

What is gametes

Sex cells
Sperm and eggs
Pollen and ovule

51

Chromosome complement

Humans have 23 different chromosomes but since we have 2 sets we have 46 in total

52

How much of each chromosome do we posses

2 copies
One from mum and one from da

53

What name is given to cell division

Mitosis

54

How are the number of chromosomes accurate

Before a cell divides it must make a copy of its genetic material so that each cell is identical

55

Importance of mitosis

Daughter cells produced by mitosis are genetically identical to the mother cell necessary as it ensures there is no loss of genetic material so the daughter cell contains all the necessary genes and carry out cell functions

56

Mitosis explanation

Parent cell at rest
Chromosphere become visible under the microscope
Chromosomes become condensed
Nucleus dislikes and chromosomes line up along the equator spindle fibres attach to each centromere
Spindle fibres contract and begin to separate the chromatids
Chromatically are pulled to each pole of the cell once there are called chromosomes again
Nuclei reform around each set of chromosome
Cytoplasm divides forming 2 genetically identical daughter cells

57

Contract

Become shorter

58

Condensed

Shorter and thicker

59

DNA

Deoxyribonucleic acid

60

Where is DNA found

Inside the nucleus of most cells

61

What are chromosomes made from

DNA

62

Wha does DNA contain

All instructions ( genes) needed for an organism to carry out all of its cells functions and processes

63

What instructs the cell

Genes instruct the cell to make specific proteins

64

What is a protein

Substance made by a cell

65

What are the four bases

Thymine
Guanine
Cytosine
Adenine

66

What are the base pairing rules

Adenine only bonds with thymine
Guanine only bonds with cytosine

67

What does the sequence of bases in DNA determine

The order of the bases of the amino acids in proteins made by cells

68

What do the different combinations of bases produce

Different genes Which code for different proteins

69

What does DNA contain

The genetic code ( genes)

70

What are genes

Sequences of DNA that contain the instructions (code) which allows cells to make proteins

71

In order for proteins to be assembled what occurs

A copy of DNA which has instructions needs to be transported from the nucleus to the ribosome

72

What chemical carries the genetic code and to where

mRNA to the ribosome

73

What does mRNA do

Provides the corrects sequence which codes for a particular sequence of amino acids and proteins

74

Functions of protein

Enzymes
Antibodies
Hormones
Structural
Receptors

75

Impact of limiting factors

If one factor affects rate of photosynthesis is limiting then plant makes less glucose than it would under optimum temp
Cell growth slows down and less food is stored as starch

76

Limiting factors examples

Light
Temperature
Carbon dioxide concentration

77

What is glucose

Carbohydrate

78

What do carbohydrates contain

Elements carbon, hydrogen and oxygen

79

What can glucose do

Be used in respiration to generate energy ATP
Stored as starch ( storage carbohydrate)
Made into structural carbohydrate cellulose as part of the cell wall of plant

80

products of photosynthesis

Oxygen (waste)
Glucose (useful)

81

Raw materials photosynthesis

Water
Carbon dioxide

82

Equation photosynthesis

Carbon dioxide plus water plus light energy absorbed by chlorophyll turned into oxygen and glucose

83

Stage 1 photosynthesis

Light reactions
Light energy trapped by chlorophyll and converted to chemical energy in form of ATP
Some light energy used to split water into oxygen and hydrogen
Oxygen diffuses out of plant as a by product
Hydrogen and ATP are passed on to stage 2 cannot happen without these
Occurs in chloroplasts

84

Stage 2 photosynthesis

Carbon fixation
Controlled by enzymes in the form of a cycle
Occurs in chloroplasts
Carbon dioxide from air diffuses into leaf and reacts with hydrogen from stage 1 to form glucose
The energy needed for this reaction is produced by ATP from stage 1

85

What is photosynthesis

Process in which plants make their own food

86

What do chloroplasts contain

A green pigment which gives green plants their green colour

87

What can a respirometer do

Used to measure rate of respiration
Rate of oxygen uptake and carbon dioxide output can be analysed and a rate of respiration can be calculated

88

What does respiration require

Oxygen

89

What does respiration produce

Carbon dioxide data about the rebate of oxygen uptake and carbon dioxide output

90

In plant and yeast cells what is pyruvate converted to

Carbon dioxide and ethanol in the cytoplasm

91

How much ATP are generated in fermentation

2 ATP

92

Does aerobic respiration require oxygen

Yes

93

Does fermentation require oxygen

No

94

How is glucose broken down in fermentation

Partially

95

How is glucose broken down in aerobic respiration

Completely

96

End products aerobic respiration

Carbon dioxide and water

97

End products fermentation

Ethanol and carbon dioxide in plants and lactate in animals

98

Where does fermentation occur

Cytoplasm

99

Where does aerobics respiration occur

Begins in cytoplasm and is completed in mitochondria

100

Fermentation equation plant and yeast cells

Glucose to carbon dioxide and ethanol and 2 ATP

101

Why 37 degrees

At which an enzyme is at its most active it's optimum temp

102

Degradation

Some enzymes promote breakdown of complex molecules into simpler ones

103

Synthesis

Some enzymes promote reactions which bring about the building up of complex molecules from simpler ones

104

Denatured

High temp change shape of enzyme
Do not destroy it
When it cools down does not go back to original shape

105

What can proteins such as enzymes be damaged by

pH and alkalis

106

What is the working range

Shows the range of pH that enzyme is able to work within

107

What is a catalyst

Speed up the rate of chemical reactions

108

What happens at the active site

Enzyme plus substrate
Enzyme substrate complex
Enzyme plus product

109

Why are enzymes so specific

Members with only the exact right shape will bind together to the enzyme and react
These are the reactant or substrate molecules

110

What is the active site

Very specific shape and the most important part of the enzyme
Substrate binds

111

Aerobic respiration equation

Glucose plus oxygen into carbon dioxide plus water plus 38 ATP

112

Why do neurones need so many mitochondria

Transmitting impulses

113

Why do muscle cells need so many mitochondria

Contracting

114

Why do sperm cells need so many mitochondria

For swimming

115

Aerobic respiration

Food broken down to pyruvate stage 1
From breathing and is needed for stage 2 to occur in mitochondria
Produced in stage 2 and released from the cell as a waste product
Useful product 2 produced in stage 1 36 ATP produced in stage 2 need for cell activities

116

Fermentation in plant and yeast cells

Pyruvate converted into carbon dioxide and ethanol in the cytoplasm
Root cell in waterlogged soils are deprived of oxygen
Fermentation results in only 2 ATP being generated

117

Stage 1 in aerobic respiration

Occurs in cytoplasm
Glucose is broken down to 2 molecules of pyruvate by enzymes
2 molecules of ATP per molecule of glucose
Oxygen is not needed

118

Stage 2 aerobic respiration

Occurs in mitochondria
Pyruvate from stage 1 diffuses into cell from the cytoplasm into the mitochondria and enzymes break it down further into carbon dioxide and water
36 ATP generated
Only occurs when oxygen is present