Answer:
The correct statement concerning the cell membrane lipid molecules is that "energy is not expended during diffusion" (Option d)
Explanation:
Biological membranes are formed by two lipidic layers arranged with their hydrophilic polar heads facing the exterior and the interior of the cells, and their hydrophobic tails against each other. Membranes are fluid, which means that molecules that form it have the capability to move through it.
Lipids can easily change places with other neighbor lipids by <u>lateral diffusion</u> in the same layer. This is passive diffusion, which means that it does not need energy to happen.
Lipids can also diffuse transversally to the other layer, but this kind of movement is not as easy as lateral diffusion.
There are also other lipidic movements as rotational diffusion that imply the rotation of the molecule.
Through this lipidic bilayer, there is also a passive transport of some particles from one side of the cell to the other which happens because of concentration differences.
Answer:
1500
Explanation:
Let's assume that the allele for yellow seed color is "Y" and the allele for green seed color is "y". Genotype of pure breeding yellow seeded plant would be "YY" and that of the green seeded plant would be "yy". A cross between YY and yy gives all heterozygous yellow seeded plants (Yy) in F1 progeny. Self pollination of two F1 plants (Yy x Yy) obtains F2 generation in 3 yellow: 1 green ratio.
The total population size of F2 generation = 2000
The proportion of yellow seeded plants in F2 generation = 3/4 (since the F2 phenotype ratio is given 3 yellow: 1 green)
Therefore, total number of yellow seeded plants in F2 progeny = 3/4 x 2000= 1500
Answer:
Treatments and Therapies. Anxiety disorders are generally treated with psychotherapy, medication, or both. Psychotherapy or “talk therapy” can help people with anxiety disorders.
Explanation:
Answer:
Human Activitys.
Explanation
The goods we use, travel around the world very quickly, and they often carry uninvited species with them.
Answer:
Let the "barred" allele be caller B and the "non-white" allele b. Since chickens use chromosomes 
and 
to determine sex, hens would have chromosomes 
, and roosters would have chromosomes 
. A Z-linked gene is represented as a superscript on the chromosome, 
for the dominant allele and 
for the ressesive allele.
A barred hen would have a copy of B on its Z chromosome, a non-barred rooster would have both copies of b on both Z chromosomes. Using Punnet squares to represent the crosses we get the following cases:
That is a ratio of two barred heterozygote roosters to two non-barred hens. Crossing them we get:
That is a ratio of one barred heterozygote rooster to one barred hen to one non-barred rooster to one non barred hen.
