Hi the T and B cells change after contact with the pathogen is a-- acquired-- immune response.
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Answer: Women are carriers for the disease hemophilia because hemophilia is an X-linked disease. The recessive allele for the disease is found on the X chromosome.
The sons of carrier women get hemophilia because males have one X chromosome and one Y chromosome. The sons of a carrier woman may inherit the affected X chromosome from their mother, and a Y chromosome from their father. They have only one X chromosome and one it's affected, will result in hemophilia.
Explanation: Women are carriers because in most cases, only one of their two X chromosomes are affected. The two female X chromosome is rarely affected.
Daughters of carrier women will not get the disease because they need two affected X chromosomes to manifest the disease. So even if they inherit one affected X chromosome from their mother, the second X chromosome they will inherit from their father will be normal. Therefore, daughters of carrier women can only be carriers.
Radioactive isotopes got scattered in the experiment which contained radion, however, the bacteria didn't have a high amount of radiation. You even eat radiation every day. For Example, a banana has approximately 1/1,000,000 sieverts. in order for that radiation to kill you, you would need the radiation of 2 sieverts, or 2 trillion bananas.
Sponges absent
Cnidarians not jointed (Aquatic organisms, all have tentacles with nematocysts - stinging cells, used to capture food.)
Roundworms absent (AKA nematodes are unsegmented, colorless and do not have appendages).
Annelids not jointed (With the exception of leeches, all annelids have chitonous hair-like structures projecting from their cuticle. These appendages fulfill different functions in different species.)
Mollusks not jointed (Invertebrates that lack hard appendages such as legs or antennae)
Arthropods jointed (the arthropods are the only invertebrates to have jointed appendages)
Echinoderms not jointed (Due to their radial symmetry, all echinoderms have appendages which point outward from the center of the body like the spokes on a wheel.)
and vertebrate jointed
Answer: Aristotle's and Linnaeus's classification systems both divided all life into two groups: plant and animal.