Answer:
The question lacks options, the options are:
parents?
A.100% red/white-feather chickens.
B.50% white-feather chickens and 50% red/white-feather chickens.
C.33% white-feather chickens, 33% red-feather chickens, and 33% red/white-feather chickens.
D.25% white-feather chickens, 25% red-feather chickens, and 50% red/white-feather chickens
The Correct answer is D
Explanation:
According to the question, the hybrid chicken has a mixture of red and white feather phenotypes expressed at the same time. This tells us that the red and white alleles are CODOMINANT in the chicken i.e. none is dominant or recessive over the other.
Let's assume that (R) allele is the red feather colour while (r) allele is for white feather colour. Therefore, the red/white feathered chicken will have a Rr genotype. In a cross between two red/white feathered chicken (Rr), the following offsprings will be produced RR, Rr, Rr and rr
RR- Homozygous red feather d chicken (1/4 × 100=25%)
Rr- Hybrid Red/White feathered chicken (2/4 × 100=50%)
rr- Homozygous white feathered chicken (1/4 × 100=25%)
Answer:
Cycads /ˈsaɪkædz/ are seed plants that typically have a stout and woody (ligneous) trunk with a crown of large, hard, stiff, evergreen and (usually) pinnate leaves. The species are dioecious, therefore the individual plants of a species are either male or female. Cycads vary in size from having trunks only a few centimeters to several meters tall. They typically grow very slowly[3] and live very long, with some specimens known to be as much as 1,000 years old.[citation needed] Because of their superficial resemblance, they are sometimes mistaken for palms or ferns, but they are not closely related to either group.
Cycads are gymnosperms (naked seeded), meaning their unfertilized seeds are open to the air to be directly fertilized by pollination, as contrasted with angiosperms, which have enclosed seeds with more complex fertilization arrangements. Cycads have very specialized pollinators, usually a specific species of beetle. Both male and female cycads bear cones (strobili), somewhat similar to conifer cones.
Cycads have been reported to fix nitrogen in association with various cyanobacteria living in the roots (the "coralloid" roots).[4] These photosynthetic bacteria produce a neurotoxin called BMAA that is found in the seeds of cycads. This neurotoxin may enter a human food chain as the cycad seeds may be eaten directly as a source of flour by humans or by wild or feral animals such as bats, and humans may eat these animals. It is hypothesized that this is a source of some neurological diseases in humans.[5][6]
Cycads all over the world are in decline, with four species on the brink of extinction and seven species having fewer than 100 plants left in the wild.[7] The plant has a very long fossil history, with evidence that they existed in greater abundance and in greater diversity before the Jurassic and late Triassic mass extinction events.
Explanation:
~Dr.Smiley~
(Jane)
The answer is ganglia. As indicated, they house many cell
bodies of afferent and efferent neurons.
Spinal ganglia are located in the dorsal (that contain cell bodies of afferent
neurons) and ventral roots (that house cell body
of efferent neurons) of a spinal nerve.
The incorrect among the choices is "<span>direct signaling involves the activation of g proteins"
This is incorrect because direct signaling does not involve the activation of g proteins rather it involves the activation of ion channels resulting to either an excitation reaction (depolarization of the membrane) or an inhibition reaction (hyperpolarization of the membrane); and this will ultimately affect the action of the organ the nerve is innervating.</span>
<u>Answer:</u>
<em>It is not true to say that common ancestors occurs only within a single species rather two species with similar traits might have a common ancestor. </em>
<u>Explanation:</u>
If the ancestor is same for both the species then it is said that both the species are closely related and share common ancestor with similar evolutionary relationship.
Phylogenetic tree are drawn and studies are done to understand the ancestor of a species. The evolution has occurred from the ancestor to the new species formed.