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aqa gcse bio 9-1d > 6. Cell Division & DNA > Flashcards

6. Cell Division & DNA Flashcards

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1
Q

Why does mitosis take place?

A
  • growth

* replace damaged cells

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2
Q

What has to happen before mitosis?

A

The chromosomes replicate

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3
Q

How many divisions are there in mitosis?

A

1

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4
Q

Are the cells haploid or diploid in mitosis?

A

Diploid (in mammals)

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5
Q

How many new cells are produced in mitosis?

A

2

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6
Q

Are the new cells identical or different in mitosis?

A

Identical

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7
Q

What does diploid mean?

A

Has a full set of chromosomes

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8
Q

What does haploid mean?

A

Half the number or chromosomes

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9
Q

What can meiosis also be referred to as?

A

Reduction division

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10
Q

Where does meiosis only happen?

A

In the cells of the reproductive organs

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11
Q

What does meiosis produce?

A

Gametes

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12
Q

Where are gametes produced in animals?

A

Ovaries and testes

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13
Q

Where are gametes produced in plants?

A

Ovule and anther

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14
Q

How many chromosomes do the gametes produced in meiosis have?

A

Half the number of the parent cell (humans - 23 chromosomes instead of 23 pairs of chromosomes)

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15
Q

How many copies of each chromosome do gametes have? Why?

A

One so when they fuse the zygote has the normal amount of chromosomes

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16
Q

Are gametes diploid or haploid?

A

Haploid

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17
Q

Are zygotes diploid or haploid?

A

Diploid

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18
Q

What happens to the zygote formed at fertilisation?

A

Divides by mitosis to produce more cells that differentiate as embryo develops

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19
Q

How does meiosis turn one cell into four new cells in humans?

A
  • diploid cell in ovaries or testes (46 chromosomes)
  • chromosomes replicate (still 46 chromosomes)
  • pairs of chromosomes line up at equator, thicken and spindles attach
  • chromosome pairs separate into two new cells and a nucleus reforms
  • spindles attach to the (2) duplicates of chromosomes and duplicates are pulled apart into separate cells
  • four new cells have formed (23 chromosomes)
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20
Q

How does meiosis turn one cell into four new cells in general?

A
  • diploid cell
  • chromosomes replicate
  • pairs of chromosomes line up at equator, thicken and spindles attach
  • chromosome pairs separate into two new cells and a nucleus reforms
  • spindles attach to the (2) duplicates of chromosomes and duplicates are pulled apart into separate cells
  • four new cells have formed
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21
Q

How many chromosomes are in a human cell produced by mitosis?

A

46

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22
Q

How many chromosomes are in a human cell produced by meiosis?

A

23

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23
Q

What are the two gametes produced by humans?

A

egg and sperm

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24
Q

How do mitosis and meiosis differ in terms of the number of daughter cells produced?

A

Mitosis produces two daughter cells whereas meiosis produces four daughter cells

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25
Q

How do mitosis and meiosis differ in terms of the number of cell divisions that occur?

A

In mitosis one cell division occurs whereas in meiosis two occur

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26
Q

How do mitosis and meiosis differ in terms of the nature of the cells they produce?

A

Mitosis produces genetically identical cells whereas meiosis produces cells that are all genetically different

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27
Q

How do mitosis and meiosis differ in terms of when it occurs?

A

Mitosis occurs during growth and asexual production whereas meiosis occurs during sexual reproduction

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28
Q

How do mitosis and meiosis differ in terms of the number of chromosomes that are passed on to their daughter cells?

A

In mitosis one copy of each chromosome goes to each of the new daughter cells, whereas in meiosis only half of the chromosomes go to each of the new daughter cells

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29
Q

How do mitosis and meiosis differ in terms of what other names they can be called by?

A

Mitosis is otherwise known as copying division whereas meiosis is otherwise known as reduction division

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30
Q

Why is important that the four daughter cells produced in meiosis contain half the number of chromosomes?

A
  • to restore the original chromosome number when they get fertilised
  • to prevent the doubling of the chromosome number
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31
Q

What is the difference between mitosis and meiosis?

A
  • in mitosis two daughter cells are produced; in meiosis four are produced
  • in mitosis there is one cell division; in meiosis there are two
  • mitosis produces genetically identical cells; meiosis does not
  • mitosis occurs during asexual production; meiosis occurs during sexual production
  • in mitosis one copy of each chromosome goes to each of the new daughter cells; in meiosis only half of the chromosomes go to each of the daughter cells
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32
Q

How do asexual and sexual reproduction differ in terms of how many parents are involved?

A

Asexual needs one parent whereas sexual involves the mixing of genetic information from two organisms

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33
Q

How do asexual and sexual reproduction differ in terms of fertilisation?

A

In asexual there is no fusion of gametes wheres in sexual gametes fuse

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34
Q

How do asexual and sexual reproduction differ in terms of their offspring?

A

In asexual offspring are genetically identical to that parent whereas in sexual offspring are genetically different from either parent

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35
Q

How do asexual and sexual reproduction differ in terms of genetic variation?

A

In asexual variation is caused by random mutations whereas in sexual offspring are genetically different from their parents

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36
Q

How many daughter cells are produced in mitosis?

A

2

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37
Q

How many daughter cells are produced in meiosis?

A

4

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38
Q

How many cell divisions occur in mitosis?

A

1

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39
Q

How many cell divisions occur in meiosis?

A

2

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40
Q

When does mitosis occur?

A

During growth and asexual reproduction

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41
Q

When does meiosis occur?

A

In the formation of gametes during sexual reproduction

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42
Q

What can mitosis also be referred to as?

A

Copying division

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43
Q

What can meiosis also be referred to as?

A

Reduction division

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44
Q

How many parents are involved in asexual reproduction?

A

1

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45
Q

How many parents are involved in sexual reproduction?

A

2

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46
Q

What process allows asexual reproduction to occur?

A

Mitosis

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47
Q

How is genetic variation caused during asexual reproduction?

A

Random mutations

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48
Q

Examples of asexual reproduction?

A
  • strawberry runners
  • potato runners
  • starfish
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49
Q

What are the female gametes in animals?

A

Egg cells (ova)

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50
Q

What are the male gametes in animals?

A

Sperm

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51
Q

Where are female gametes produced in animals?

A

Ovaries

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52
Q

Where are male gametes produced in animals?

A

Testes

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53
Q

What are the female gametes in plants?

A

Egg cell nucleus

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54
Q

What are the male gametes in plants?

A

Pollen grain nucleus

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55
Q

Where are the female gametes produced in plants?

A

Ovary of carpel

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56
Q

Where are the male gametes produced in plants?

A

Anther of stamen

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57
Q

What is the form of asexual reproduction in bacteria?

A

Binary fission

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58
Q

Advantages of sexual reproduction?

A

Variation in the offspring increases the chances of survival if circumstances change

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59
Q

Why does genetic variation increase chance of survival?

A

If circumstances change some individuals will survive the chance due to having different characteristics

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60
Q

Disadvantages of sexual reproduction?

A
  • slow

* finding a mate takes time and energy

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61
Q

Advantages of asexual reproduction?

A
  • only needs to be one parent so no energy or time is wasted finding a mate
  • large numbers of clones are produced when conditions are favourable
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62
Q

Disadvantages of asexual reproduction?

A

Vulnerable to extinction due to lack of variation - could easily catch disease

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63
Q

Which organisms can reproduce sexually and asexually depending on their circumstances?

A
  • mosquitoes (malaria)
  • fungus (releasing spores)
  • plants that produce seeds sexually but reproduce sexually
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64
Q

How does malaria reproduce sexually and asexually?

A

The parasite reproduces sexually when it’s in the mosquito and asexually when it’s in the human host

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65
Q

How does fungus reproduce sexually and asexually?

A
  • asexually-produced spores form fungi that are genetically identical to the parent fungus
  • sexually-produced spores introduce variation and are often produced in response to a change in the environment
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66
Q

How do plant species reproduce sexually and asexually?

A
  • produce their seeds sexually

* reproduce asexually e.g. daffodil bulbs - new bulbs divide off main bulb but each bulb grows into new identical plant

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67
Q

Where does the asexual reproduction of malaria take place?

A

In the human liver and red blood cells

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68
Q

Where does sexual reproduction of malaria take place?

A

In the mosquito, triggered by the lower body temperature

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69
Q

How does sexual reproduction of malaria occur?

A
  • in mosquitoes, triggered by lower body temperature
  • in 20 minutes the sexual forms develop and burst out of the RBCs and fuse to form a zygote
  • meiosis then occurs to form new asexual parasites
  • these go to infect human hosts
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70
Q

What chemical are chromosomes made of?

A

DNA

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71
Q

What is genetic information carried on?

A

Chromosomes

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72
Q

What is a section of DNA called?

A

A gene

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73
Q

What does DNA stand for?

A

Deoxyribonucleic acid

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74
Q

What is all the genetic material in a cell composed of?

A

DNA

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75
Q

What is DNA?

A

A polymer of nucleotides, made up of two stands forming a double helix

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76
Q

Where is DNA found in?

A

Chromosomes

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77
Q

What does a nucleotide consist of?

A

A common sugar and phosphate group with one of 4 different bases attached to the sugar

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78
Q

What are the four bases that DNA contains?

A

A, T, C and G

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79
Q

How many bases is the code for an amino acid?

A

3

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80
Q

What does three bases code for?

A

An amino acid

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81
Q

What does the order of bases control?

A

The order in which amino acids are assembled to produce a protein

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82
Q

Where are the genes controlling a certain characteristic located on a pair of chromosomes?

A

They are in the same location on each chromosome

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83
Q

What is the shape of a DNA molecule?

A

A double helix

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84
Q

What is a nucleotide?

A

A monomer which makes up DNA

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85
Q

What is complimentary base pairing?

A

When each base in a DNA strand links to a base on the opposite strand in the helix

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86
Q

What does A pair with?

A

T

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87
Q

What does T pair with?

A

A

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88
Q

What does G pair with?

A

C

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89
Q

What does C pair with?

A

G

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90
Q

What does each gene code for?

A

A particular sequence of amino acids which are put together to make proteins

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91
Q

How many amino acids are there?

A

20

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92
Q

How are proteins made?

A

Amino acids are put together in many different orders

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93
Q

How long is a gene?

A

Hundred or thousands of bases long

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94
Q

What is the genome of an organism?

A

The entire genetic material of that organism

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95
Q

Why does A and always pair with T and C with G?

A
  • bonds won’t form in the correct way

* physical size - bases are different lengths so there could be a bulge on the DNA if bases too long

96
Q

What has the study of the human genome allowed for?

A
  • the search for genes being linked to different types of disease
  • the understanding and treatment of inherited disorders
  • tracing human migration patterns from the past
97
Q

How does protein synthesis occur?

A
  • the code from DNA is copied to form a messenger molecule
  • this leaves the nucleus and moves to a ribosome
  • carrier molecules bring the code for specific amino acids to the ribosome and attach to the messenger molecules in the order determined by the sequence of bases
  • the amino acids are joined together in the correct order to form the protein
98
Q

What happens after a chain of amino acids has been assembled during protein synthesis?

A

It folds into a unique shape which allows the protein to perform its task

99
Q

What allows a protein to do its job?

A

It’s structure

100
Q

Examples of proteins?

A
  • hair protein (keratin)
  • hormones
  • collagen
  • enzymes
101
Q

Who discovered the structure of DNA?

A

Rosalind Franklin

102
Q

What is a mutation?

A

A random change in an organism’s DNA

103
Q

When do mutations occur?

A

All the time

104
Q

What is often the cause of mutations?

A

A mistake in the copying of DNA before a cell divides

105
Q

What arise due to mutation?

A

New forms of genes

106
Q

How can the chance of mutation be increased?

A

Exposure to some chemicals and radiation

107
Q

How can a mutation change the protein synthesised from that gene?

A
  • one of the amino acids may be substituted for another
  • this may change the intermolecular forces between the amino acids so the protein may change shape
  • it may lose function
108
Q

What do non-coding parts of DNA do?

A

Switch genes on and off

109
Q

What happens if there is a mutation to the non-coding areas of DNA?

A

It may affect how genes are expressed

110
Q

What are the different forms of a gene called?

A

Alleles

111
Q

How many alleles do gametes have?

A

1

112
Q

How many alleles do cells in an organism have, apart from gametes?

A

2 - 1 on each chromosome of a pair

113
Q

Why do we have two alleles in each cell?

A

We inherit half from our mother and half from our father

114
Q

What can an allele be?

A
  • dominant

* recessive

115
Q

What is a gamete?

A

A male or female sex cell

116
Q

What is a gene?

A

A length of DNA found on a chromosome that carries the instructions needed to make a protein

117
Q

What is a dominant allele?

A

An allele that is always expressed in the phenotype

118
Q

How is the dominant allele represented?

A

By a capital letter

119
Q

What does it mean when an organism is homozygous?

A

It has two alleles for a particular gene that are the same

120
Q

What is a genotype?

A

The alleles present for a particular gene in an organism (the letters)

121
Q

What is a chromosome?

A

A thread-like structure in the cell nucleus, made of a molecule of DNA, which carries genes

122
Q

What is an allele?

A

One of the different forms of a particular gene

123
Q

What is a recessive allele?

A

An allele that is only expressed in the phenotype if two copies are present

124
Q

How is the recessive allele represented?

A

a lowercase letter

125
Q

What does it mean when an organism is heterozygous?

A

It has two alleles for a particular gene that are different

126
Q

What is a phenotype?

A

The characteristic that is shown or expressed

127
Q

What do genetic diagrams show?

A

How certain characteristics are inherited

128
Q

What did Gregor Mendel experiment on?

A

Peas

129
Q

What was the pattern regarding sample size and the Mendelian ratio?

A

The bigger the sample size of peas, the closer to the Mendelian ratio

130
Q

Were Mendel’s results reproducible?

A

Yes

131
Q

What type of allele is polydactyly caused by?

A

Dominant

132
Q

What type of allele is cystic fibrosis caused?

A

Recessive

133
Q

What is polydactyly?

A

Having extra fingers or toes

134
Q

What is cystic fibrosis?

A

A cell membrane disorder

135
Q

Will the parent with the defective polydactyly allele also have it? Why?

A

Yes because the allele is dominant

136
Q

What is the purpose of embryo screening?

A

To detect inherited genetic disorders in embryos

137
Q

What are the two types of embryo screening?

A
  • pre-implantation genetic diagnosis (PGD)

* chorionic villus sampling (CVS)

138
Q

What happens in pre-implantation genetic diagnosis?

A
  • during IVF, a cell is removed from the embryo and its genes analysed
  • only embryos with ‘healthy’ alleles are implanted into the uterus
  • embryos with ‘faulty’ alleles are destroyed
139
Q

What happens in chorionic villus sampling?

A
  • sample of cells taken from placenta at 10-13 weeks and genes analysed
  • if the embryo has an inherited disorder, the parents can decide whether or not to terminate the pregnancy
140
Q

Arguments for embryo screening?

A
  • helps to stop people suffering from inherited disorders
  • treating disorders costs government so could reduce healthcare costs
  • during IVF most embryos are destroyed anyway
  • if an inherited disorder is diagnosed through CVS, the parents don’t have to terminate the baby
141
Q

Arguments against embryo screening?

A
  • there may come a point where everyone wants to screen their babies to pick the most ‘desirable’
  • implies that people with genetic disorders are ‘undesirable’ - could create predjudice
  • after PGD rejected embryos are destroyed - unethical
  • risk that CVS could cause miscarriage
  • expensive
142
Q

How many pairs of chromosomes are in every human body cell?

A

23

143
Q

What do the 23rd pair of chromosomes control?

A

The sex of a person

144
Q

What sex chromosomes do males have?

A

X and Y, XY

145
Q

What does the Y chromosome cause?

A

Male characteristics

146
Q

What sex chromosomes do females have?

A

Two X chromosomes, XX

147
Q

What does the XX chromosome cause?

A

Female characteristics

148
Q

Which organisms did Mendel study?

A

Peas

149
Q

What type of peas did Mendel cross in the first generation?

A

Round peas and wrinkled peas (RR and rr)

150
Q

What type of peas did Mendel cross in the second generation?

A

Round peas and round peas

151
Q

What did Mendel call what we now know to be genes?

A

Hereditary units

152
Q

Why wasn’t Mendel’s theory first accepted by other scientists?

A

They didn’t know about genes, chromosomes or DNA

153
Q

What are species?

A

A group of organisms that are able to interbreed to produce fertile offspring

154
Q

What is variation?

A

The difference in the characteristics of individuals in a population

155
Q

What can variation be caused by?

A
  • genetic causes
  • environmental causes
  • a combination
156
Q

Where do variants in a population arise from?

A

Mutations

157
Q

How often do mutations occur?

A

All the time however very rarely will it lead to a new phenotype

158
Q

What happens if a new phenotype is suited to an environmental change?

A

It can lead to a relatively rapid change in species

159
Q

What is evolution?

A

A change in the inherited characteristics of a population over time through a process of natural selection which may result in the formation of a new species

160
Q

What does the theory of evolution by natural selection state?

A

All species have evolved from simple life forms that first developed more than three billion years ago

161
Q

What happens if two populations of one species become so different in phenotype?

A

They can no longer interbreed to produce fertile offspring and have formed two new species

162
Q

When do two populations of one species become two different species?

A

When they become so different in phenotype that they can no longer interbreed to produce fertile offspring

163
Q

When does extinction occur?

A

When there are no remaining individuals of a species alive

164
Q

What are the causes of extinction?

A
  • environmental changes
  • new predator
  • new disease
  • competition
165
Q

What is the order of the general outline you need to use in a natural selection exam question?

A
  • variation
  • caused by mutation
  • which variation has an advantage and why
  • survive and breed
  • pass on advantageous genes to next generation
166
Q

What was Lamarck’s theory of evolution?

A
  • evolution of animals was caused by the inheritance of acquired characteristics
  • based on the idea that changes occur in an organism throughout it’s lifetime
167
Q

What was Darwin’s theory of evolution?

A
  • individual organisms within a species show a wide range of variation for a characteristic
  • individuals with characteristics most suited to the environment are more likely to survive
  • characteristics that have enabled these individuals to survive are passed on
168
Q

Why was the theory of evolution by natural selection only gradually accepted?

A
  • the theory challenged the idea that God made life
  • insufficient evidence to convince many scientists
  • mechanism of inheritance was not known until 50 years after the theory was published
169
Q

What does Darwin’s theory not include?

A

Ideas of genes/DNA

170
Q

Why do people have different ideas about how life began on earth?

A
  • religion
  • evidence - some theories have more than others
  • status of scientist
  • culture
171
Q

What are the conflicting theories of how life began on earth?

A
  • Darwin’s theory of natural selection
  • Lamarck’s theory of acquired characteristics
  • creationism
  • theory of intelligent design
172
Q

Why are there conflicting theories about how life on earth began?

A

Lack of evidence

173
Q

How do fossils produce evidence that species today have evolved from simpler organisms?

A
  • they are remains of organisms that lived a long time ago
  • they show changes over time
  • they have similar feature to present day species
174
Q

What are fossils?

A

The remains of organisms from many years ago

175
Q

How can fossils be formed?

A
  • from parts of organisms that have not decayed because one or more of the conditions needed to decay are absent
  • when parts of an organism are replaced by other materials as they decay
  • as preserved traces of organisms, such as footprints
176
Q

Example of fossils forming due to one or more of the conditions needed for decay being absent?

A

Insects in amber lacking oxygen for decay

177
Q

What does early forms of life being soft-bodied mean for our understanding?

A

They have few traces behind

178
Q

What are some sources of evidence for evolution?

A
  • fossils

* antibiotic resistance

179
Q

How does antibiotic resistance provide evidence for evolution?

A
  • bacteria evolve rapidly as they reproduce at a fast rate
  • bacteria can develop antibiotic resistance in a process of natural selection
  • mutations of bacterial pathogens produce new antibiotic resistant strains and the pathogens of the non-resistant strain are killed
  • population of resistant strain increases and spread
180
Q

Why do new species arise?

A
  • isolation - two populations of a species becoming separated
  • genetic variation
  • natural selection
  • speciation
181
Q

What is speciation?

A

When populations become so different that successful interbreeding is no longer possible

182
Q

What is selective breeding?

A

A process used by humans to produce different breeds of animals or varieties of plants

183
Q

How is selective breeding executed?

A
  • choosing parents with the desired characteristics from a mixed population
  • breeding these together
  • from the offspring, breed those with the desired characteristics
184
Q

Some examples of how selective breeding can be useful?

A
  • disease resistance in crops
  • animals which produce more meat/milk
  • domestic dogs with a gentle nature
  • large or unusual flowers
185
Q

What is inbreeding?

A
  • when future generations of selectively bred organisms share very similar genes
  • some diseases will be more dangerous as all the organisms would be affected
  • also there is increased risk of genetic diseases caused by recessive genes
  • also some genes would be lost, making more difficult to produce new varieties in the future
186
Q

What are some of the limitations of selective breeding?

A

Inbreeding:

  • more prone to disease
  • increased risk of genetic diseases
  • smaller gene pool
187
Q

What is genetic engineering?

A

A process which involves modifying the genome of an organism by introducing a gene from another organism

188
Q

What are the additional small pieces of genetic material in bacterial cells?

A

Plasmids

189
Q

What does the vector do in genetic engineering?

A

It is used to insert the gene into the required cells

190
Q

What is the vector usually during genetic engineering?

A

A bacterial plasmid or a virus

191
Q

Example of genetic engineering?

A

Gene for making human growth hormone inserted into sheep - so they will produce the hormone in their milk

192
Q

What are some current applications for plant genetic modification?

A
  • disease and pest resistant plants
  • keeping fruit and vegetables fresher for longer
  • plants that have increased nutritional benefits
  • producing soy with higher levels of anti-cancer proteins naturally found
193
Q

Advantages of genetic engineering?

A
  • treating diseases

* more efficient food production

194
Q

Disadvantages of genetic engineering?

A
  • long term effects e.g. changing genes could pass on problems to future generations
  • same with GM crops (changing genes may get into general circulation)
195
Q

Ethical issues of genetic engineering?

A
  • not a natural process and interfering with nature

* altering organisms for human gain seen to be against God’s will

196
Q

What is cloning?

A

When an identical copy of an organism is made

197
Q

What process is usually involved in cloning?

A

Mitosis (binary fission in bacteria)

198
Q

What are the four ways of cloning organisms?

A
  • cuttings
  • tissue culture
  • embryo transplants
  • adult cell cloning
199
Q

Advantages of using cuttings to clone plants?

A

They reproduce quickly and is quicker than tissue culture

200
Q

How is tissue culture used to clone plants? (process)

A
  • small tissue sample taken from parent plant and grown in agar with nutrients and hormones to form tissue
  • tiny identical plants are formed and then grown on
201
Q

What is an important condition that needs to be used when cloning cells using tissue culture?

A

The agar needs to be sterile so you don’t have bacteria contaminating it

202
Q

Advantages of using tissue culture to clone plants?

A
  • plants can be made very quickly
  • in very little space
  • all year round
203
Q

How are embryo transplants used to clone animals? (process)

A
  • each embryo is divided into individual cells and each cell grows into an embryo in the lab
  • embryos are transferred to host mothers
  • identical cloned calves are born
204
Q

In embryo transplants, what embryo is used initially?

A

From particular cattle e.g. a prized bull semen with a prized cow egg

205
Q

In embryo transplants, how does each cell grow into an embryo?

A

By mitosis

206
Q

In embryo transplants, who are the cloned organisms identical to?

A

Each other, but not the mothers that gave birth to them

207
Q

Advantages of embryo transplants to clone animals?

A

Produces hundreds of ideal offspring

208
Q

How is adult cell cloning used to clone animals? (process)

A
  • nucleus removed from unfertilised egg cell and nucleus from adult body cell is inserted into egg cell
  • electric shock stimulates egg cell to divide to form embryo
  • inserted into womb of an adult female
209
Q

Benefits of cloning?

A
  • lots of ideal offspring quickly produced with ideal characteristics
  • could help preserve endangered species
  • lead to a greater understanding of development of the embryo and age-related disorders
210
Q

Concerns of cloning?

A
  • cloned animals may not be as healthy as normal ones
  • reduced gene pool
  • may lead to cloning of humans
211
Q

What is the disadvantage if there is a reduced gene pool?

A

Fewer alleles available if there is an environmental change so if a new disease appeared, all might be wiped out

212
Q

What is classification?

A

When organisms are put into groups depending of their structure and characteristics

213
Q

What system did Carl Linnaeus develop?

A

The binomial system

214
Q

Who developed the binomial system?

A

Carl Linnaeus

215
Q

What did Linnaeus classify living things into?

A
  • kingdom
  • phylum
  • class
  • order
  • family
  • genus
  • species
216
Q

What is the mnemonic to remember the binomial system?

A

King prawn curry or fat greasy sausages

217
Q

What is the mnemonic to remember the binomial system? (and what they stand for!)

A
  • king - kingdom
  • prawn - phylum
  • curry - class
  • or - order
  • fat - family
  • greasy - genus
  • sausages - species
218
Q

What is the kingdom of humans?

A

Animalia

219
Q

What is the phylum of humans?

A

Chordata

220
Q

What is the class of humans?

A

Mammalia

221
Q

What is the order of humans?

A

Primale

222
Q

What is the family of humans?

A

Hominidae

223
Q

What is the genus of humans?

A

Homo

224
Q

What is the species of humans?

A

sapien

225
Q

What is the largest group in the binomial system?

A

Kingdom

226
Q

What is the newer model of classification?

A

The ‘three domain system’

227
Q

Who was the ‘three domain system’ developed by?

A

Carl Woese

228
Q

Why were new models of classification proposed?

A

Evidence of internal structures became more developed due to improvements in microscopes

229
Q

What are organisms divided into in the three domain system?

A
  • archaea
  • bacteria
  • eukaryota
230
Q

What are archaea?

A

Primitive bacteria usually living in extreme environments

231
Q

What do eukaryota include?

A

Protists, fungi, plants and animals

232
Q

What are the six kingdoms that organisms are classified into?

A
  • archaebacteria
  • eubacteria
  • protista
  • fungi
  • plantae
  • animalia
233
Q

What method is used to show how sciensts believe organisms are related?

A

Evolutionary trees

234
Q

What do evolutionary trees do?

A

Show how scientists believe organisms are related

235
Q

What do evolutionary trees use?

A

Current classification data for organisms and fossil data

236
Q

What is the importance of the binomial system for scientists around the world?

A

So all scientists use the same genus/species names so avoid confusion

aqa gcse bio 9-1d (7 decks)

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