OCR Biology > 4.3 CLASSIFICATION/EVOLUTION > Flashcards

4.3 CLASSIFICATION/EVOLUTION Flashcards

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1
Q

Define binomial system

A
  • A system that uses the genus name and species name to name organisms
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2
Q

State the mnemonic for the modern classification system

A

Dear
King
Phillip
Cried
Out
For
Goodness
Sake

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3
Q

State the eight taxonomic classification levels

A

1) Domain
2) Kingdom
3) Phylum
4) Class
5) Order
6) Family
7) Genus
8) Species

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4
Q

State four advantages of the classification system

A

1) For our convenience
2) Makes studying living things more manageable
3) Easier to identify organisms
4) Help us identify relationships between species

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5
Q

Describe the domain classification level

A
  • There are three domains
    1) Archaea
    2) Eubacteria
    3) Eukaryotae
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6
Q

Describe the kingdom classification level

A
  • There are five kingdoms
    1) (Eukaryotes - have a nucleus) plantae, animalia, fungi, protoctista
    2) Prokaryotae (no nucleus/single celled)
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7
Q

Describe the phylum classification level

A
  • A major subdivision, contains all the groups of organsisms that have the same body plan (e.g backbone)
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8
Q

Describe the class classification level

A
  • A group of organisms that all posses the same general traits (e.g leg number)
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9
Q

Describe the order classification level

A
  • a subdivision relate to further information about the organism (e.g carnivora or herbivora)
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10
Q

Describe the family classification level

A
  • A group of closely related genra (e.g in carinivora there is cat family and dog family)
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11
Q

Describe the genus classification level

A
  • A group of closely related species
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12
Q

Describe the species classification level

A
  • Members capable of interbreeding, show some variation but are essentially the same
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13
Q

State the trend in relative ease of classification down the taxonomic levels

A
  • Becomes more difficult
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14
Q

State the binomial system name of humans

A

Homo sapiens

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15
Q

State three disadvantages of the common name method

A

1) The same organism may have a different common name in different areas/countries
2) The same common name may be used for different organisms in different areas/countries
3) Translation of languages may give an incorrect/different name

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16
Q

State the biological definition and phylogenetic definition of species

A

Biological = a group of organisms that can freely interbreed to produce fertile offspring
Phylogenetic = a group of individual organisms that are very similar in appearance, anatomy, physiology, biochemistry and genetics

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17
Q

Describe the features of prokaryotae in detail

A
  1. No nucleus
  2. Contain a loop of naked DNA
  3. No membrane bound organelles
  4. Smaller ribosomes
  5. Cells are smaller than eukaryotes
  6. Can be free living or parasitic
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18
Q

Describe the features of protoctista in detail

A
  1. EUKARYOTES
  2. Most are single celled
  3. Have autotrphic or heterotrophic nutrition
  4. Mostly free living
  5. Show a very wide variety of forms
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19
Q

Describe the features of fungi in detail

A
  1. EUKARYOTES
  2. Chitin walls
  3. Mostly free living and saprophytic
  4. Has many nuclei in the cytoplasm
  5. Can exist as single cells or mycelium (with hyphae)
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20
Q

Describe the features of plantae in detail

A
  1. EUKARYOTES
  2. Are multicellular
  3. Have cellulose cell wall
  4. Are autotrophic
  5. Contain chlorophyll
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21
Q

Describe the features of animalia in detail

A
  1. EUKARYOTES
  2. Are multicellular
  3. Are heterotrophic
  4. Able to move around
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22
Q

Define convergent evolution

A
  • When unrelated species look very similar because of the similar ways in which they have adapted to their environment
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23
Q

State which process causes slight differences in biological molecules between organisms

A
  • Evolution
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24
Q

Explain how the extent of similarity/difference in versions of the same biological molecules can determine evolutionary relationships

A
  • Two organisms with very different versions of the same molecules are less closely related because they have evolved separately for longer
  • Two organisms with very similar versions of the same molecules are more closely related because they have not evolved separately for long
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25
Describe the **evidence** that **cytochrome c** gives about **evolutionary relationships**
- If the **amino acid sequence** of **cytochrome c** is the **same**, the **two species** are **closely related** - If the **amino acid sequence** of **cytochrome c** is the **different**, the **two species** are **not closely related** - (the **more differences** the **less closely related**)
26
State and explain the **type** of **organsism** that **cytochrome c** is **present** in
- **ALL** organisms that **respire** because its the **protein** used in **respiration**
27
Define **genetic code**
- The **instructions** for producing **proteins**
28
Explain how **DNA** can be used as evidence for **evolutionary relationships**
- The more **similar** the **sequence** in a part of **DNA**, the more **closely related** the **two species** - Because they have **not** **evolved separaetly** for a **long time**
29
State the **three-domain classification** system
1) **Bacteria** 2) **Archaea** 3) **Eukaryotae**
30
State **structural differences** between the **bacteria** against **archae** and **eukaryotae** in the **three domain classification** system
**Bacteria** have: 1) A **different cell membrane strcuture** 2) **Flagella** 3) **Different organelles** 4) **No proteins** associated with their **genetic material** 5) A **different mechanism** for **DNA replication** and for **synthesising RNA** 6) **Different enzymes** used to **synthesise RNA**
31
State **structural similarities** between the **archae** and **eukaryotae** in the **three domain classification** system
**Archae** and **eukaryotae** both have: 1) **Similar** mechanisms for **DNA replication** and **synthesising RNA** 2) Production of **proteins** that are **associated** with their **DNA** 3) **Similar enzymes** used to **synthesise RNA**
32
Define **phylogeny**
- The study of **evolutionary relationships** between **organisms** (how **closely different species** are **related**)
33
Define **artificial classification** and **natural classification**
**Artificial classification** = classification based on a **few characteristics** for **human convinience**, in a way thats **easy** to **remember/find** **Natural classification** = classification that reflects the **real evolutionary relationships** between organisms (e.g the **modern classification system**)
34
Compare **four** features of **artifcial classification** against **natural classification**
**Artificial** classification: 1) Based on only a **few chracteristics** 2) Does **not** reflect **evolutionary relationships** 3) Provides **limited information** 4) **Doesnt change** **Natural** classification: 1) Based on **many chracteristics** 2) Reflects **evolutionary relationships** 3) Privides **useful information** 4) **Changes** alot with **advancing information**
35
Define **monophyletic species**
- A **group** of **species** that belong to the same **phylogenetic group** and **share** a **common ancestor**
36
State the **four** **observations** that **darwin** made
1) **Offspring** genrally appear **similar** to their **parents** 2) **No two individuals** are **identicle** 3) **Organisms** have the ability to produce **large numbers** of **offspring** 4) **Populations** in nature tend to **remain** a **fairly stable size**
37
State **darwins conclusions**
- There is **struggle** to **survive** - **Better adpated** individuals **survive** and pass their **characteristic** to the **next generation** - Overtime, a number of **changes** may give rise to a **new species**
38
Describe how **variation** leads to **evolution** according to **darwins research**
1) When too many young are produced, there is **competition** for **food/resources** 2) As **offspring** are **different**, some may be **better adapted** than others 3) The **better adpated individuals** obtain enough **food/resources** to **survive** long enough to **reproduce** 4) They then pass these **advantagous characteristics** onto the **next generation** 5) The population can **change/evole** to become **better suited** to its **environment**
39
State and explain the **two** pieces of **evidence** for **evolution**
1) **Fossil evidence** (**fossil species** are similar to **current** **species** but **current species** seem to be **better adpated**) 2) **Biological molecules** (If **one species** gives **rise** to **another** they are likey to have the **same biological molecules**/two **closely related** **species** will have only **separated** **relatively** **recently** so their **biological molecules** will be **identical** or **similar**)
40
Explain how **fossils** can give **evidence** for **evolution**
- **Fossils** show **change overtime** - There are **methods** to **date fossils** - They show **relationships** between **species/organisms** - **Fossil species** are similar to **current** **species** but **current species** seem to be **better adpated**
41
Expain how **biological molecules** can give **evidence** for **evolution**
- If **one species** gives **rise** to **another** they are likey to have the **same biological molecules** - Two **closely related** **species** will have only **separated** **relatively** **recently** so their **biological molecules** will be **identical** or **similar** - (e.g **Cytochrome C** and **DNA gene sequences**)
42
State and explain how **mitochondrial DNA** provides **evidence** for **natural selection**
- During **sexual reproduction** the **mitochondrial DNA** in the **egg** is **passed** down to the **offspring** - **ONLY** **maternal mDNA** is passed to **offspring**, **NEVER** the **paternal mDNA** - We can **trace back** an organisms **mDNA** to determine **migration patterns** (shows **change**)
43
Define **variation**
- The **differences** between **individuals**
44
State the **six** different forms of **variation**
1) **Interspecific variation** 2) **Intraspecific variation** 3) **Environmental variation** 4) **Genetic variation** 5) **Continuous variation** 6) **Discontinuous variation**
45
Define **intraspecific variation**
- The **variation** between members of the same **species** (e.g different **niches** for each **member**)
46
Define **interspecific variation**
- The **differences** between **different species** (e.g different **behaviour** between **cats** and **dogs**)
47
Define **enironmental variation**
- **Variation** caused by **response** to **environemntal factors** (e.g **light intensity**)
48
Define **genetic variation**
- **Variation** caused by the **possesion** of **different allele combinations** (e.g **blood group**)
49
Define **continuous variation**
- **Variation** where there is **two extremes** and a full range of **values inbetween** (e.g **human height**, **tree leaf length**, **flagella number** on **bacteria**)
50
Define **discontinuous variation**
- **Variation** where there are **distinct catergories** and **nothing inbetween** (e.g **sex**, **human blood groups**, weather **bacteria** have **flagella** or **not**)
51
State how to show **CONTINUOUS variation** in **data form**
- A **histogram**
52
State how to show **DISCONTINUOUS variation** in **data form**
- A **bar chart**
53
Give an example that describes how **environemtal factors** could be **limited** by **genetic factors**
- Regardless of how **nutritional** your **diet** is, you may be unable to grow **tall** is yout **height** is **limited** by your **genes/genetics**
54
Give an example that describes how **genetic factors** could be **limited** by **environemntal factors**
- Not all **genes** are **active** all the time, certain **environmental factors** can **active/deactivate gene expression**
55
Define **adaptation**
- A **characteristic** that **enhances survival** in the **habitat**
56
State **four** things a **well-adapted** individual will be able to do
1) Find **food**/**photosynthesise** well 2) **Defend** itself from **predators/disease** 3) **Survive** the **abiotic** factors of its **environement** (e.g **temperature/water availibility/pH/light**) 4) Resond to **changes** in its **environment**
57
State the **three** types of **adaptation**
1) **Anatomical** adaptations 2) **Behavioural** adaptations 3) **Physiological** adaptations
58
Define **anatomical adaptation**
- **Internal/external structural** features
59
Define **behavioural adaptation**
- The ways that **behaviour** (**response** to **change**) is **modified** for **survival**
60
Define **physiological adaptation**
- Ensuring **functioning** of **processes** are occuring at the **cellular level**
61
State and explain **five anatomical adaptations** of **marram grass**
1) **Long/widespread roots** - enables sufficient **water/nutrient absorbance** and **stabilises sand dunes** 2) **Curled leaves** - **reduces** the **SA** of the leaf that is **exposed** to the **wind** thus **moisture** builds up 3) **Waxy cuticle** - **reduces** the **water wavpour loss** by **evaporation** 4) **Hairs** on **lower epidermis** **reduces air** movement so **water vapour** is **retained** close to the **lower epidermis** 5) **Fewer stomata** means **less water vapour loss**
62
State and explain the **two behavioural adaptations** of **marram grass**
1) **Rolling** the **leaf** more **tightly** and **closing** the **stomata** when there is a **shortage** of **water** to **reduce transpiration** 2) When covered by **sand** it will **grow faster** to reach **sunlight**
63
State and explain **four biochemical (physiological) adaptations** of **marram grass**
1) **Specialised hinge cells** lose **water/turgidity** which allows for the **leaf** to **curl** up as a **response** to **low water availability** 2) **Guard cells** control opening and closing of **stomata** via **turgidity** 3) **Maintains** a **lower water potential** than normal plants to enable survival in **salty conditions** 4) **Leaves** contain many **lignified cells** that provide **support** when **turgidity** is **lost** so **leaf** stays **upright** even when **water** is **unavailable**
64
State the **similarities** of marsupial and placental **moles**
- **Cylindrical body** - **Small eyes** - **Strong front legs** - **Large claws** on **front legs** - **Short fur** - **Short tail** - **Tough skin nose**
65
Explain **covergent evolution**
- When **different species** occupy **similar environments** - Similar **selection pressures** - Results in **selection** for **similar adaptations** - Thus, the **different species** end up looking more **similar** than they **genetically** are
66
Outline the process of **natural selection**
1) **Mutations** create alternative **alleles** 2) This creates **genetic variation** between a **species** (**intraspecific variation**) 3) **Scarce resources** create **selection pressure** 4) Individuals with an **advantageous characteristic** will survive and **reproduce** 5) Their **offspring** then **inherit** that advantageous **allele** 6) The **next** **generation** will have a **higher proportion** of individuals with the **advantageous characteristics**
67
Give an example of a **selection pressure**
- Exposure to **pesticides**/**insecticides**/**antibiotics**
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