Hi there!
A prezygotic isolating mechanism is a mechanism that causes something to happen, not allowing the organisms to breed before fertilization. I'll explain each one for you.
A - That is postzygotic because the organisms were not stopped before fertilization. The result is a sterile organism.
B - Again, that is postzygotic because the organism was produced.
C - This is prezygotic! The sperm dying shows that something is in action to prevent fertilization, meaning that it cannot happen.
D - Fertilization was successful, so it is postzygotic.
ANSWER:
C - the sperm dies when it reaches the female tract
If you need help with any more problems, feel free to message me and I'd be more than happy to help you work through them and provide explanations.
Hope this helps!! :)
If there's anything else that I can help you with, please let me know!
Acting as levers for movement is a function of: bones.
Movement can be defined as a process through which several skeletal muscles in the body systems act together as a group, in order to cause a change in the motion of a body part.
Basically, bodily movement are produced when skeletal muscles exerts a force on the tendons, which in turn pull on the bones (levers) and other supporting structures such as the skin.
In the body of living organisms, bones act as levers for movement by enhancing limb speed or power of limb movements while joints act as a fixed point of movement (fulcrum).
Read more: brainly.com/question/24279781
Answer:
Eukaryotes are organisms whose cells have a nucleus enclosed within a nuclear envelope. Eukaryotes belong to the domain Eukaryota or Eukarya; their name comes from the Greek εὖ and κάρυον. The domain Eukaryota makes up one of the domains of life in the three-domain system; the two other domains are Bacteria and Archaea. Eukaryotes represent a tiny minority of the number of living organisms; however, due to their generally much larger size, their collective worldwide biomass is estimated to be about equal to that of prokaryotes. Eukaryotes evolved approximately 1.6–2.1 billion years ago, during the Proterozoic eon.
Explanation:
Answer: DF508 mutation. A Genetic, Hereditary, Autosomal and Recessive Mutation.
Explanation:
Cystic fibrosis (CF) is a recessive autosomal lethal disease, it is most common on Caucasoid populations. Its diagnosis is suggested by the clinical features of chronic obstructive pulmonary disease, persistent pulmonary colonization (particularly with mucoid Pseudomonas strains), meconium ileus, pancreatic insufficiency with or familiarity history of the disease. The FC gene is large, with about 250 Kb of genomic DNA, 27 exons representing about 5% of genomic DNA; encodes a 6.5 kb transcribed mRNA. This mRNA is transcribed into a protein of 1480 amino acid called CFTR (Regulator Transmembrane Conductance Cystic Fibrosis). When a three-base pair deletion, adenosine-thymine-thymine (ATT) identified in the CFTR gene, exon 10, it results in the loss of a single amino acid phenylalanine at position 508 of the protein. This mutation is called DF508; “D” stands for deletion and “F” for phenylalanine amino acid.
Answer:
Water is polar and oil is nonpolar so the substances won't mix.
Explanation:
Water is polar covalently bonded within the molecule. This unequal sharing of the electrons results in a slightly positive and a slightly negative side of the molecule. oils are nonpolar, so they will remain separate from molecules of a polar solvent such as water.
