Answer:
Earliest- gametophyte dominance, sporophyte dependence
Middle- sporophyte dominance, gametophyte independence
Recent- sporophyte dominance, gametophyte dependence
Explanation:
The life cycle of plant alternates between the two phases: the haploid gametophyte which produces gametes and the diploid sporophyte which produces spores. The evolution of land plants shows how these are dependent on each other in terms of the requirement of nutrition.
In bryophytes, the gametophyte is the dominant phase on which the sporophyte depended. Later in pteridophytes, the sporophyte became dominant which is present in the later evolved groups namely the gymnosperms and the angiosperms. The gametophyte was independent on the sporophyte but in angiosperms and gymnosperms, it is dependent.
Water is a unique molecule which contains inter-molecular forces like vandar wall's forces and hydrogen bonding that results in extremely strong bonding forces among water molecules.
Cohesion and adhesion are the properties of water which refer to the fact that water molecules are not only very strongly attracted to water molecules but also to other polar molecules of any type.
This is the cohesive nature of the water which makes water a water drop and it is the adhesive nature of water due to which water takes the shape and available space in a glass or jar of water .
How these properties are a result of bonding between atoms?
Cohesive properties:
- We are well aware of the fact that water is composed of one atom of oxygen and two atoms of Hydrogen.
- The two hydrogen atoms align themselves in such a way that oxygen is in middle of them. Due to great electronegativity difference Oxygen gets a partial negative charge while Hydrogen atoms get partial positive charges.
- Now one oxygen atom of one one water molecule attracts the partial positive charged hydrogen atom of another water molecule, and this attraction causes the bonding. This type of inter-molecular forces of atom gives water cohesive properties.
Adhesive properties:
- If we talk about adhesive properties through which water is attracted to other materials of polar nature, these adhesive properties are also due to same nature of bonding.
- Any polar compounds can easily get bonded with water due to polar nature of water molecules. You can see the attached figure for better understanding of bonding properties of water.
Hope it help!
Answer:
Troponin
Explanation:
This is a complex of three proteins (Trop C, I, T) that are responsible for muscle contraction of the skeletal and cardiac muscles . its binds with protein tropomysin to lie in the grove between the actin filaments. its prevents contraction by blocking myosin crossbridge in a relax muscles.Inorder to aid contractions calcium ions binds with troponin, which leads to confrontational change.This exposes myosin on actin filaments, leading to formation of crossbridge and therefore contraction of muscles.
Therefore if there is a mutation in the gene that encoded Troponin, as explained above, calcium ion will not be able to bind with tropinin, and there will be no exposure of myosin on actin filaments, no binding of myosin on actin to cause crossbridge, and consequently no muscle contraction,
Thus the intercoastal muscle and diaphragm will not contract leading to death of the baby.