B. J. is a 5-year-old boy who has suffered from repeated upper respiratory infections since he was 16 months old. At 4 years of age, he was diagnosed with allergic asthma. The following winter, at age 5, he was admitted to the hospital twice for acute asthma with a secondary bacterial pulmonary infection. At the second admission, a complete blood count, sputum culture, and immune status work-up were ordered. Laboratory Data

Assay Patient Results Reference Range
Hemoglobin 13.5 g/dL 11.5-14.5 g/dL
Hematocrit 40% 33-43%
Total WBC count 16.2 x 10^9/L 4-12 x 10^9/L
Lymphocyte Count 4.3 x 10^9/L 2.7-5.4
T lymphocytes 2.4 x 10^9/L 2.7-5.3
B lymphocytes 1.0 x 10^9/L 0.6-1.4

Required:
What is the etiology of this patientâs recurring infections?

regulation of gene expression. gene expression can be regulated by various cellular processes with the aim to control the amount and nature of the expressed genes. these regulatory proteins bind to dna and send signals that indirectly control the rate of gene expression

explanation:

brain development. a child's brain undergoes an amazing period of development from birth to three—producing more than a million neural connections each second. the development of the brain is influenced by many factors, including a child's relationships, experiences and environment.

explanation:

the answers are as following:

1. c. double helix, nucleosome, coil, supercoil, chromosome

2. b. g2 phase, preparation for mitosis

3. d. interphase consists of the g1, s, and g2 phases

4. c. metaphase

5. a. chromosomes are duplicated before cell division so that each new daughter cell has a complete set