Answer:
Option D
Explanation:
Options for the question
A)import seeds produced in the southern hemisphere.
B)plant the flowers out-of doors in november.
C)keep the plants in a warm growing environment.
D)expose the plants to an hour of light in the middle of each night until the end of april.
Solution
Since Chrysanthemum is a short-day plant, its flower mainly develop during night and hence they require long nights of 11 to 12 hours. Blackout system is sometimes used to induce flowering.Flowering can be delayed by regulating both light and temperature. this is done by exposing plants for a short period of time to light (can be artificial) and to some source of heat that produces 85° F or higher temperature.
Thus if flowers are required in month of may, flowering can be delayed by exposing Chrysanthemums plant to light and heat source during night time
Option D is correct
Answer:columnar describes cell shape.
Simple describe the number of layers
Explanation: epithelial tissues are one of the four major tissues of the body.the others being nervous, muscular, connective tissues.
Epithelial tissues are made up of thin cells that cover the external and internal surface of the body.
The cells may form one layer or more and they occur in several shapes.if they form one layer ,it is called simple.if they form several layers,it is called stratified.
Some are called pseudo-stratified because the cells occur with varying lengths and give the impression of stratified but they are actually made up of one layer.
Simple columnar epithelium is a single layer of tall, closely packed cells. They possess cellular extensions ,such as microvilli in the small intestine, or the cilia in the female reproductive tract.
Answer:
they are so for..
both of them are comprised of similar tissues working together to perform a particular task.
In human blood, there is a compound inside the RBCs called haemoglobin which ensures that the muscle will receive enough oxygen during exercise.
<h3><u>Explanation:</u></h3>
In human blood, the red blood corpuscles contain the haemoglobin. Haemoglobin is a iron chelated compound containing porphyrin ring and a globin tail which can establish co-ordinate covalent bond with both oxygen and carbon dioxide. The bonding element depends on the concentration of these two gases. In lungs, where the oxygen concentration is more than carbon dioxide, the haemoglobin bonds with oxygen and brings it to the tissues where carbon dioxide concentration is more. This makes the haemoglobin to release oxygen and bond with carbon dioxide which is brought back to lungs. This is the process by which each and every tissue including the muscles recieve oxygen.
In muscles there is Myoglobin which is another iron-porphyrin compound which has several times more affinity for oxygen than haemoglobin. This helps to extract more oxygen from haemoglobin in muscles.