Answer:
Contracting muscle fibers do not always shorten.
Explanation:
Skeletal muscle fibers may be defined as the fiber that contain the single muscle cell that is cylindrical in nature. The connective tissue present in muscle is epimysium.
The contraction of the skeletal muscle fiber helps in the movement of the body. The contraction of the muscle fiber do not means that the muscle fiber gets shorten. The thick and thin filaments remains in their original length and the sarcomere shortens only.
Thus, the correct answer is option (C).
Answer:
Land plants evolved from a group of green algae, perhaps as early as 850mya
Answer:
Chromosome number variation: B. Down syndrome
Loss-of-function allele : D. PKU
Physiological trait
: E. Lactose metabolism
Discovery-based science
: A. Human Genome Project
Genetic cross: C. Model organism
Explanation:
Down syndrome is a condition in which there is an extra copy of the chromosome number 21. Hence, it is a chromosome number variation.
Physiological traits refers to any function of a body. Hence, it matches with lactose metabolism.
Human Genome Project was a project under which the whole genome of the humans were sequenced. Hence, it is a discovery based science.
A genetic cross is made between model organisms to test for the offsprings that would be produced from a cross. Hence, genetic cross and model organism math with each other.
1. The stem should be cut at least three to four inches above the ground surface level.
2. The stem should be fixed tightly into the glass capillary.
3. The connection should be made air-tight, using paraffin wax.
4. Initial and final mercury levels should be carefully noted.
5. The experiment should be preferably performed in the morning time.