C. a rise in blood carbon dioxide concentration
Explanation:
Negative feed back mechanism refers to the control mechanism in which a product of a particular pathway controls the switch on and switch off of that particular pathway.
Since breathing increases the blood oxygen concentration and lowers carbon dioxide concentration and pH. The sensors that regulate the breathing should respond to oxygen concentration as the carbon dioxide is the by-product of respiration and is responsible for increasing blood pH. Thus increased Carbon dioxide levels in blood is the only factor which will trigger breathing.
Answer:
Yes.
Explanation:
Yes, the statement is right because in chemical war, great damage occurs to all living organisms that has a bad effect on our environment. These chemicals are very dangerous so its usage in the war has long term effects on the environment and the organisms that live in it. Both the opponents receive great damage from this chemical war and the destruction of the natural beauty of the place vanished where this war occurs so this vanished of beauty and organisms is the defeat of both the opponents that fought this war.
Explanation:
The problem says that the hairless phenotype never breeds true. That means that it's not the result of a homozygous genotype (H₁H₁ or H₂H₂), so it is caused by the heterozygous genotype (H₁H₂).
The <u>expected </u>offspring from the cross between two Mexican hairless would be:
<h3>P
H₁H₂ x
H₁H₂</h3><h3>F1 1/4
H₁H₁, 2/4
H₁H₂ and 1/4
H₂H₂.</h3>
And the <u>expected</u> phenotypic ratio 3:1. However, the observed offspring shows a 2:1 ratio. What's happening?
If the observed phenotypic ratio in the offspring of a monohybrid cross (a single gene with two alleles) is 2:1, we can suspect that one of the genotypes is lethal in homozygosis and therefore does not appear in the progeny (the puppies are born dead).
If we proposed that the H₂ allele is lethal in homozygosis, then:
- The H₁H₁ genotype would cause normal puppies --> 1
- The H₁H₂ genotype would cause hairless puppies --> 2
- The H₂H₂ is lethal and causes the death of puppies --> 0
The phenotypic ratios change to 2:1, as observed in the experiment.
<span>A major difference between the eccrine sweat glands and the appocrine sweat glands is that eccrine glands empty into/onto the skin surface while apocrine glands empty into/onto the hair follicle.
There are two types of sweat gland, eccrine and apocrine. As the eccrine glands empty into the skin surface, they are present all over the body particularly on forehead, palms and feet. That's why we feel more sweat on these parts of the body. while apocrine glands empty into/onto the hair follicles so they are mostly armpits.</span>
Answer:
Class I: Hepaticopsida ( Liverworts)
Class II: Anthocerotopsida ( Hornworts)
Class III: Bryopsida ( Mosses)
Explanation:
Bryophytes are small plants that grows in moist and shady places.They don't attain great heights because of absence of roots, vascular tissues, mechanical tissues and cuticle. They are terrestrial but require external water to complete their life cycle. Hence they are called as the" amphibians" of the animal kingdom.
Class I: Hepaticopsida or Hepaticae
- Gametophytic plant body is either thalloid or foliose. If foliose the lateral appendages are without midrib.
- Rhizoids without septa
- Each cell in the thallus contain many chloroplasts
- Sex organs are embedded in the dorsal surface
- Capsule lacks columella
- Sporophyte may be simple having only one capsule or differentiated into root, seta and capsule
- It has 4 orders: Calobryales, Jungermanniales, Spherocarpales and Marchantiales
Class 2: Anthocerotae or Anthocerotopsids:
- Gametophytic plant body is simple, thalloid;thallus dorsiventra without air chambers shows no internal differentiation of tissues
- Scales are absent in the thallus
- Each cell of the thallus possess a single large chloroplast with a pyrenoid
- Sporophyte is cylindrical only partly dependent on gametophyte for its nourishment. It is differentiated into bulbous foot and cyclindrical capsule. Seta is meristematic.
- Endotheciumforms the sterile central column in the capsule. It have ony one order Anthocerotales
Class 3: Musci or Bryopsida
- Gametophyte is differentiated into prostrate protonema and an erect gametophores
- Gametophore ids foliose, differentiated into axis and lateral appendages like leaves but without midrib.
- Rhizoids are multicellular with oblique septa
- Elaters are absent in the capsule of sporangium
- The sex organs are produced in seperate branches immersed in a group of leaves.
- It has only three orders: Bryales, Andriales and Sphagnales
Bryophytes are used as a packaging material for fragile goods, glasswares etc.Mosses are good source of animal food in rocky and snow clad areas. Decoction prepared by boiling Sphagnum in water is used for the treatment of eye disease.