Asymmetry is the lack of symmetry.
Answer:
Adaptive immune responses are triggered by activation of antigen-specific T cells that produce antibodies against foreign antigens such as, for example, harmful viruses. These immune responses are useful to eliminate dangerous molecules from the body. In a normal immune reaction, the antibodies produced by T-cells target antigen molecules in order to be subsequently absorbed by phagocytic macrophage cells.
Autoimmune diseases are triggered by the response of the adaptive immune system against self-antigen molecules. Since the immune system can not eliminate antigens from the own body, this immune reaction generates an excessive inflammatory response, and it may lead to the damage of tissues and organs.
Answer:
1. false
2. true
3. true
Explanation:
1. Annuals are the plants that complete their life cycle in one season or one year. These are the herbaceous plants that grow, flower and die in one season. Examples of annuals are geranium, marigold, etc.
2. In a flower, the whorl of petals is called corolla while the whorl of the sepal is known as calyx. In flowers, calyx and corolla together make perianth. The calyx is outer to corolla in a perianth.
3. The fruit is a matured and ripened ovary that provides protection to the seeds present in it. Fruits are formed after fertilization and may contain one or more seeds. Tomatoes are the simple berry fruits while cucumber is pepo, the modified berries. Broccoli is the flower head while celery is the edible leaf.
The answer is the 1st statement.
Answer:
The fusion of a egg and a sperm produces a zygote with 46 (2n) chromosome number.