Answer:
ai) P= Red blood cell Q= Alveoli
ii)1. It gives the lungs a large surface area to volume ratio.
2. It is moist and thin.
b) P has a disc or biconcave shape which allows the O2 to bind to it with the help of a protein called haemoglobin for it to be transferred to various parts of the body.
c) Carbon monoxide will bind to the haemoglobin to form carboxyhaemoglobin causing oxygen disruption
The correct option is this: A STRONG WIND BLOW ACROSS A MIDWESTERN PRAIRIE.
A strong wind is an example of a natural force. The prairie refers to a land fill with grasses and that is a natural factor also. Thus, a strong wind that is blowing across a prairie is generating a natural form of energy. The energy flow in the other options given are examples of man made devices.
Answer: Stratigraphy and Biostratigraphy
Relative dating is a method of determination of age, in which one object or organism is compared with the other object or organism found in the heap of strata. It is a method for determining the relative order of the past events, without stating the absolute age.
Stratigraphy is a branch of geology that studies the relative position of the sediments and rocks in the strata with respect to the geological timescale. Biostratigraphy is the branch of stratigraphy which deals with the relative aging of fossils with respect to the strata in which these are found defining a particular period of geological time scale.
If we subtract the atomic number from the weight, we get the number of neutrons in the particle. This is because protons and neutrons each have a weight of 1, while electrons are 0. And since the atomic number is also the number of protons in the atom, subtracting it from total weight gives us the number iif neutrons.
Answer:
The correct answer is- Immune system
Explanation:
There are physical, chemical and immunological barriers present in our body which helps us to protect from the foreign antigen. They all assist each other and helps in pathogen removal from our body.
The physical barrier includes skin, gastrointestinal tract, respiratory tract, etc which do not allow the microbe to enter the body. Chemical barriers include tear, saliva, acid in the stomach which kills microbes on the body surface.
Immune cells like macrophages, B cells kills microbes when it gets in the body. Lymphatic system also contain immune cells and helps in microbe removal.
So the immune system is assisted by physical barrier, chemical barrier, and lymphatic system.
