Close friend and supporter of Charles Darwin especially in his theory of evolution. 1868 examined samples of mud recovered from the deep-sea floor 11 years back to discover a surface layer of thick mucus-like material with small embedded particles on the samples. Bathybius haeckeliiafter famous naturalist Ernst Haeckel Subdivisions looked to move so he assumed they were a form of living protoplasm and he named the "organism".
The blood vessels farthest from the heart must have valves.
The valves which are present in the blood vessels prevent the backflow of the blood back into the specific organ.
There are different valves present in the heart are:
- The tricuspid valve is situated between the right atrium and right ventricle.
- The pulmonary valve is between the right ventricle and the pulmonary artery.
- The mitral valve is between the left atrium and left ventricle.
- The aortic valve is between the left ventricle and the aorta.
Other vales which are present in the blood vessels are in leg. Leg veins do require the valves. If not present the blood will go back down into the feet because of the gravity. Thus there are various valves present in the leg veins.
Valves in veins are bicuspid, meaning they have two flap-like structures that regulate blood flow in the vein.
To know more about the Valves, refer to this link:
brainly.com/question/12926213
#SPJ4
The statement that best describes a human influence on the biogeochemical cycles is : A. Increased eutrophication caused by high levels of nitrogen and phosphorous
In this process, the amount of nutrients in water will dramatically increased, creating abnormal growth for the algae
hope this helps
Answer by YourHope:
Which adaptation allowed gymnosperm plants to out-compete spore-bearing plants?
seeds
:)
Independent assortment states that all alleles are inherited independently of other alleles. This helps diversity because it helps to further the randomization of traits. If traits were always inherited together, as a "package deal", there would naturally be less diversity than the situation that exists. For example, one may never see a person with blue eyes and brown hair if the alleles for the two traits, hair and eye color, were inherited together. However, it is worth noting that there is "genetic linkage", meaning full or partial violation of independent assortment among certain trait groups.
There are 46 chromosome in a normal human diploid cell, 23 inherited from the mother's egg and 23 inherited from the father's sperm.
