Answer:
1. Ends of the respiratory branches are called alveoli.
2. C. To control blood flow to different areas of the body depending on activities
Explanation:
1. The trachea divides into left and right primary bronchi which in turn divide multiple times upon entering the lungs and make the bronchial tree.
The final branches of the bronchial tree are the terminal bronchioles that lead to alveoli. The alveoli are the balloon-shaped structures and serve as the site of gas exchange between the blood and inhaled air.
2. The opening and closing of sphincters of capillary beds regulate the direction of blood flow. The opening of sphincters allows the blood to flow into associated branches of capillary beds while closed sphincters direct the blood from arterioles to venules via thoroughfare channel.
This local change in blood flow is responsible for the autoregulation of blood flow to different tissues to match their respective metabolic demands. For example, during physical activity, more blood is directed to skeletal and cardiac muscles.
In plants, transpiration is a process which is inevitable but potentially harmful, because it can cause loss of water. Loss of water can lead to wilting and eventual death of the plant. Even a little stress can interfere with the plant's growth process.
But, at the same time, transpiration is necessary because of a number of reasons - the transpiration stream aids the processes of mineral absorption, water absorption, energy exchange, helps provide the plant with optimum turgidity, it helps the exchange of gases and so on.
Answer:
b. The herbicide-resistance gene is cloned into the T-DNA region of the Ti-plasmid.
Explanation:
Ti-plasmid has the ability to introduce part of its DNA (t-DNA) into the genome of host plants. This is very important for the relationship of genetic manipulation in maize plants, with the aim of inducing a gene that promotes herbicide resistance. In addition, T-DNA has many genes that code for the production of plant growth phytohormones, which is extremely important for the cloning process to work. In this case, we can assume that the correct answer for yours is the letter B.
Answer:
G1 - S - G2 (may be is option D)
Explanation:
The interface begins with phase G1 where the cell increases its volume and the mass is doubled.
Then, we continue with the S phase where DNA and histones are synthesized.
Afterwardsy we reach the G2 phase where the chromosomes are duplicated.
Finally we reach, the begining of mitosis.
