A. umbilical cord is the answer
Cell maintain homeostasis through diffusion in isotonic solution. Isotonic means that the concentrations are the same on either side of the membrane, maintaining homeostasis.
<h2>The answer is:</h2>
B) All organisms that cannot synthesize their food by means of photosynthesis or chemo synthesis are heterotrophic.
<h2>Explanation:</h2>
All those organisms that cannot manufacture their own food and instead obtains its food and energy by taking in organic substances in the process of photosynthesis usually in the animals and plants. All animals, protozoans, fungi, and most bacteria are heterotrophs.
I hope that it is correct
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.