Banded iron formations provide evidence of oxygen in the atmosphere. Banded iron formations are sedimentary rocks composed of alternating thin layers formed of iron oxide minerals, such as magnetite and hematite and silica rich minerals such as, chert and iron silicates. Most geologists agree that banded iron formations were precipitated from sea water when oxygen, produced by cyanobacteria, reacted with iron dissolved in sea water.
Hey frnd
Muscular to pump blood over long distance;
- Myogenic cardiac muscles which contract and relax rhythmically without fatigue; hence heart continues pumping;
- Cardiac muscle fibres interconnected to form a network of fibre to ensure rapid and uniform spread of excitation throughout the walls of the heart;
- Heart divided into 4 chambers which are hollow to accommodate more blood;
- Ventricles have thicker walls than auricles to generate higher pressure to drive blood over long
distance into more elaborate circulation/to the lungs and to all body tissues
Also can you you mark me BRAINLIST if I ANSWER? its D
The size of our brains has increased since we became tools users.
Explanation:
Researches have shown that since we became tool users, the size of our brain has increase significantly. This is an evolutionary footprint in us. Our brain size has not always been the same.
- The earliest humans use very crude tools in their hunting.
- Modern man is full of technology and advanced tools.
- To get here, the brain has constantly been changing over time to accommodate more innovative faculties.
From this excerpt, one can deduce that the commentary is trying to prove Susan wrong by linking how the body part of humans have changed to adapt to the environment.
The second option presents the most logical explanation for this.
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Fossils brainly.com/question/12790206
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The are coded in the arrangement of either chromosones or DNA.
