| Keyword | CPC | PCC | Volume | Score | Length of keyword |
|---|---|---|---|---|---|
| arthropods have a closed circulatory system | 1.99 | 0.4 | 4970 | 30 | 43 |
| arthropods | 0.65 | 0.1 | 1492 | 18 | 10 |
| have | 1.5 | 0.2 | 4617 | 7 | 4 |
| a | 1.42 | 1 | 3069 | 11 | 1 |
| closed | 1.68 | 0.5 | 7052 | 66 | 6 |
| circulatory | 1.94 | 0.1 | 6177 | 3 | 11 |
| system | 1.65 | 0.1 | 998 | 86 | 6 |
| Keyword | CPC | PCC | Volume | Score |
|---|---|---|---|---|
| arthropods have a closed circulatory system | 1.96 | 0.8 | 7132 | 58 |
| do arthropods have closed circulatory systems | 0.48 | 0.9 | 7953 | 39 |
| arthropods closed circulatory system | 0.12 | 0.3 | 6715 | 79 |
| do arthropods have a open circulatory system | 0.59 | 0.8 | 2676 | 93 |
| do arthropods have a circulatory system | 1.72 | 0.4 | 2395 | 13 |
| arthropods possess an open circulatory system | 0.15 | 0.5 | 4561 | 27 |
| arthropoda open or closed circulatory system | 0.87 | 1 | 7895 | 46 |
| arthropods have closed or open circulation | 0.09 | 0.1 | 5726 | 32 |
| circulatory system of arthropods | 1.36 | 0.1 | 6878 | 78 |
| open circulatory system in arthropods | 1.12 | 0.6 | 3020 | 17 |
| cephalopods have a closed circulatory system | 0.85 | 0.6 | 1349 | 42 |
| do arthropods have a respiratory system | 1.78 | 0.1 | 1784 | 19 |
| do amphibians have closed circulatory system | 0.28 | 0.9 | 8765 | 44 |
| amphibians closed or open circulatory system | 1.28 | 0.9 | 2749 | 35 |
| do cephalopods have a open circulatory system | 1.09 | 1 | 2445 | 10 |
| respiratory system of arthropods | 1.4 | 0.5 | 4647 | 45 |
| cephalopods open or closed circulatory | 1.69 | 0.6 | 5773 | 20 |
