Answer:
Crossing two chickens heterozygous for the trait feather color, when brown feathers are dominant over red feathers, will produce offspring with brown and red feathers in a brown:red phenotypic ratio of 3:1.
Explanation:
Knowing that in chickens brown feathers are the expression of the dominant allele (B) and the recessive allele is red (b), crossing two heterozygous individuals (Bb) will result in offspring that are likely to have brown or red feathers.
The cross can be represented by a Punnett Square:
<u>Bb X Bb cross
</u>
alleles B b
B BB Bb
b Bb bb
Where the result is:
<u>Genotypes</u>:
<u>Phenotypes</u>:
- Brown feathers, 75%
- Red feathers, 25%.
In this case, the probability of having brown or red feathers is 3:1.
Option 1 is the correct answer
Answer:
D: They have restricted cell division.
Explanation:
Pre cancerous cells often act like cancer cells and will grow at abnormal rates but unlike cancer cells they are unable to invade other organs
Answer:
1. myosin ATPase
2. Ca2+-ATPase
Explanation:
ATPase activity of myosin head hydrolysis ATP and energize the myosin head. The energized myosin head forms cross bridges to facilitate the power stroke of muscle contraction. The fast-twitch oxidative-glycolytic fibers have the ability to produce ATP by aerobic respiration.
These fibers have the ATPase in their myosin heads that hydrolyze ATP three to five times faster than the myosin ATPase in slow fibers. This ensures the faster speed of contraction of these fast-twitch muscle fibers.
During their relaxation, Ca2+ ATPase pumps the calcium ions back to the sarcoplasmic reticulum. As the level of Ca2+ ions in the sarcoplasm decreases, calcium ions are released from troponin. Tropomyosin is allowed to cover the myosin-binding sites on actin and the muscle fiber relaxes faster.
