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irina1246 [14]
3 years ago
13

What important event in animal evolution marks the beginning of the Cambrian period?

Biology
1 answer:
Alenkinab [10]3 years ago
3 0

The appearance of fossils would the the answer.

Although there has been some scientific debate about what fossil strata should mark the beginning of this period, the "International Geological Congress" determined that the Cambrian period was approximately 543 million years ago of which the first appearance in the fossil record of worms that made horizontal burrows was discovered.

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Why does diabetes affect the most complex organism?
labwork [276]

Answer:

The effect of diabetes on the nerves and blood vessels can also lead to problems including: 1 Trouble with digestion. 2 Sexual dysfunction. 3 Slow wound healing.

Explanation:

4 0
3 years ago
Professional psychological associations require researchers to minimize infection, illness, and pain in animal subjects.
Vladimir79 [104]

Answer:

The correct answer D.  

Explanation:

The professional psychological association established some ethical regulation known as The APA ethics code that is an essential ethic code for psychological researchers to work.

It has many standards related to the clinical practice of psychology but main concerned ethical standard are taking consent, no use of non-primates and cat or dogs as animal subject and other like debriefing, deception and many other. It allows subjects like rats or mice for clinical purposes.

Thus, the correct answer is an option - D.

6 0
3 years ago
Read 2 more answers
Star-shaped cells that twine around nerve cells to form a supporting network in the brain & spinal cord is called ____(A) As
skelet666 [1.2K]

Answer:

Astrocytes

Explanation:

Astrocytes are the most abundant cells in the central nervous system that twine around nerve cells supporting the brain and spinal cord. They perform many functions; such as providing the nuerons with nutrients, control the blood brain barrrier and blood flow. Astrocytes are basically responsible for maintaining the central nervous system homeostasis.

3 0
2 years ago
1. What is the difference in the base pairing rules for DNA and RNA?
vladimir2022 [97]

Answer:

1.

DNA

A-T

G-C

RNA

A-U

T-A

G-C

2.

TAC CGA GAT GCA TTC

3.

AUG GCU CUA CGU AAG

8 0
3 years ago
Please match the following
Eva8 [605]

Answer:

1. Ovary

2. uterus

3. Testosterone

4. Ovum

5. Fallopian Tubes

6. Estrogen

7. Scrotum

8. Puberty

9. Reproductive system

10. Testis

Explanation:

The numbers correspond with the left column.

Hope This Helps!

8 0
2 years ago
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