Answer: Mouth.
Explanation:
The mouth is known to be performing both the tasks of chemical digestion and mechanical digestion.
The food is ingested through mouth and the teeth perform the process of mechanical digestion by breaking down the food particles into smaller particles.
Then the saliva gets mixed into the food and the enzymes(amylase) present in the saliva helps in the digestion of carbohydrates.
So, mouth is the organ that performs the process of both mechanical and chemical digestion.
Answer:
The correct answer is option D. Light and some other factors are necessary for chlorophyll production
Explanation:
By this experiment, it is clear that light is the major factor that helps in the production of chlorophyll in seedlings or plants. In this study, placing the seeds in the light turns 75 seedlings green which is possible by the production of the green pigment, chlorophyll only. So, it is proved that light is a key factor in the production of chlorophyll.
Besides light, there must be some other factors (mineral nutrition and chemical metabolites) that also play role in the production of chlorophyll or increase or decrease of the chlorophyll production as few seedlings did not turn green in the study.
Answer:
7
Explanation:
There are always half the chromosomes in sex cells.
Force required = F = ?
mass of the car = m = 1200 kg
initial velocity of the car = Vi = 10 m/sec
final velocity of the car = 0
time required to stop the car = t = 20 sec
Using Newton`s 2nd law of motion;
F = ma ………………………(1)
as a = Vf - Vi / t , put this value in equation (1)
F = m ( Vf - Vi /t ) ………………(2)
F = 1200 ( 0 - 10 /20) = - 600 N
here Negative sign shows that external force is acting in opposite direction of the motion to bring it to rest.
we can also calculate this force by using the relation
Rate of change of momentum = net force acting on the object …………(3)
m Vf - m Vi / t = net force acting on the object
m (Vf - Vi / t) = F
1200 ( 0 - 10 /20) = - 600 N = F
so, net force acting on the object =F = - 600 N
The correct answer is A. Experimental group
Explanation:
In experiments, the experimental group refers to the group of subjects that receives special treatment or in which the scientist or researcher intervenes. This is the opposite of a control group that does not receive treatment and therefore, it is used as a reference to measure the effect of the treatment.
This implies, in the experiment presented Group A is the control group as they do not have special treatment because they sleep normally and Group B is the experimental group as the researcher modifies their sleep time and reduces it two hours which means in this group there is a treatment or intervention.
