Answer:
body size
more
circulatory system
egg deposition
Explanation:
Because of their large <em>body size</em> , ancestral amphibians likely faced challenges supporting themselves out of the aquatic environment.
Although there was far <em>more</em> oxygen available to gills in air than in water, the delicate structure of gills couldn't be supported in the terrestrial environment.
The costs of locomotion on land and greater oxygen demand from enlarged muscles led to modifications of the heart and <em>circulatory system</em>
These early amphibians could not venture too far away from water because <em>egg deposition</em> was restricted to moist environments.
Answer:
A)11,460 years
Explanation:half of a radioactive element represent the time take for half of it's components to dissociate or disintegrate.
For carbonn14 that undergo an emmision to form a stable carbon 14,it moves thus
14C(1 part) ______14C(0.5 parts)_____14C(0.25parts)
i.e it undergo two radioactive decay which means two half lives .
Since each half life is 5780 years ,the age will be 2×half lives= 2×5780=11,460 years
Hey there!!
There are three points which help us to identify a plant cell
( 1 ) Check whether chlorophyll is present
( 2 ) The vacuoles would be large
( 3 ) The cell wall would be present
Hope helps!
Answer:
Point mutations are a broad category of mutations that describe a change in a single nucleotide of DNA, such as a substitution for another nucleotide, deletion of a nucleotide, or insertion of a single nucleotide into the DNA, resulting in DNA that differs from the normal or wild type gene...
or you can say:
Point mutations are a large category of mutations that describe a change in single nucleotide of DNA, such that that nucleotide is switched for another nucleotide, or that nucleotide is deleted, or a single nucleotide is inserted into the DNA that causes that DNA to be different from the normal or wild type gene ...
Answer:
Channel proteins form hydrophilic channels to passively transport substances down the concentration gradient.
Carrier proteins bind to substances to transport them actively against the concentration gradient. They do not form channels.
Explanation:
Channel proteins are the membrane proteins that serve in transport of small polar molecules and/or ions by making a hydrophilic pore across the membrane. These molecules diffusion through the pore and exhibit facilitated diffusion.
Carrier proteins are the membrane proteins that transport the substances across the membrane by binding to them. They do not form the hydrophilic channels. Carrier proteins serve in the active transport of molecules against the concentration gradient.
