Answer:
Porifera or Sponges
Explanation:
Porifera is the phylum of the simplest multicellular marine animals. Their body is composed of two cell layers (something like tissues) and mesophyl between them. The body is in direct contact with surrounding water through the large number of pores and channels. What makes Sponges so simple is that their cells are unspecialized and that they don't have nervous, digestive or circulatory systems.
The answer is A-Sand
I took a test with that same question and I got it right!.
Answer:
2.447 × 10⁴ years
Explanation:
Step 1: Given data
- Half-life of the radioactive atom (t1/2): 3,500 years
- Parent-daughter ratio ([A]/[A]₀): 1:127 (1/127)
Step 2: Calculate the rate constant
Radioactive decay follows first-order kinetics. We can calculate the rate constant (k) using the following equation.
k = ln2 / (t1/2) = ln2 / 3,500 y = 1.980 × 10⁻⁴ y⁻¹
Step 3: Calculate the time elapsed (t)
For first-order kinetics, we will use the following expression.
ln ([A]/[A]₀) = -k × t
t = ln ([A]/[A]₀)/ (-k)
t = ln (1/127) / (1.980 × 10⁻⁴ y⁻¹) = 2.447 × 10⁴ y
Answer:
B. identifying the regions of human DNA that are transcribed into RNA
C. identifying the regions of human DNA that bind to proteins
D. analyzing the regions of human DNA that vary among individuals
Explanation:
The double helix structure of the deoxyribonucleic acid (DNA) molecule was characterized and published in April 1953 by Francis Crick and James Watson. Moreover, the Human Genome Project was a project aimed at completing mapping and sequencing of the human genome. This project was completed and published in April 2003. Nowadays, scientists are focused on identifying which genes are expressed (i.e., transcribed into RNA) in specific cell types/tissues. For this purpose, it is imperative 1-to identify the promoter and enhancer regions that bind to specific proteins (transcription factors) in order to activate gene expression, and 2-to understand how genetic variation is related to gene expression patterns in specific cell types and/or in response to specific environmental stimuli.
