BIOLOGY HIGH SCHOOL

Select the best answerWhich of the following events define the Proterozoic eon?

-eukaryotic cells first seen
-stable continents
-first bacterial fossils
-Cambrian explosion
-oxygen builds up in atmosphere

Answers

Answer 1
Answer: proterozoic eon - oxygen builds up in atmosphere. 
Answer 2
Answer:

Eukaryotic cells first seen

oxygen build up

stable continents

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Why do naturalists suggest that we plant more trees?
How is the process of natural selection involved in evolution?
A child gets a severe blow to the head from an accident. Although her eyes are still fully functional, she can no longer see. Based on this information, her doctor determines that the brain area most likely damaged in the accident is the ________ lobes.

What are the different blood types

Answers

There are four blood types they are A, B, AB, and O

How are salts formed?A) By the covalent bonding of neutral atoms.

B) By the covalent bonding of oppositely charged ions.

C) By the ionic bonding of a cation and an anion.

D) By intermolecular hydrogen bonding.

Answers

the answer would be C by thr ionic bonding

What is semen? an exocrine gland near the opening of the urethra a structure located on the outside of the male body a combination of sperm and other reproductive fluids a production of fluid that gives the sperm nourishment.

Answers

Semen is a combination of sperm and other reproductive fluids. Semen is a complex fluid that plays an important role in male reproduction. Hence option c is correct.

What is semen?

Semen is a fluid that is ejaculated from the male reproductive system during sexual intercourse or other forms of sexual activity. It is composed of a mixture of fluids, including seminal fluid and spermatozoa (sperm cells).

The seminal fluid, which makes up the majority of semen, is produced by three glands: the seminal vesicles, the prostate gland, and the bulbourethral gland. These glands secrete fluids that provide nutrients and protection for the sperm, as well as a suitable environment for them to survive and function properly.

The seminal fluid contains various substances such as fructose, amino acids, enzymes, and prostaglandins, which help nourish and protect the sperm as they travel through the female reproductive tract.

The spermatozoa are produced in the testes and are responsible for fertilizing the female egg during sexual reproduction. The semen acts as a transport medium for the sperm, enabling them to reach the female reproductive system and potentially fertilize an egg.

Therefore, option c is correct.

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Answer:

C

Explanation:

On e2020

Which mutation would be most beneficial to an elephant and its descendents?A.
a mutation of the hemoglobin allowing better oxygen-carrying capacity

B.
a mutation of the tail fur so it becomes course and thick

C.
a mutation of the skin color resulting in an albino (white) elephant

D.
a mutation of the tusk size and length resulting in smaller and shorter tusks

Answers

The correct answer is (a.) a mutation of the hemoglobin allowing better oxygen-carrying capacity. The mutation of the hemoglobin that allows a better oxygen-carrying capacity would be the most beneficial to an elephant and its descendants. 

Answer:

What was the answer

Explanation:

Was the answer A or D?

Buffer zones _A. Can help regulate the aciditiy of aquatic ecosystems
B. Help increase erosion rates
C. Are set up around natural resource areas
D. All of the above

Answers

C. Are set up around natural resource areas

the answer is c. Are set up around natural resource

What three components make up nucleotide?

Answers

The three components make up nucleotide are nitrogenousbase, sugar, phosphate group.

Nitrogenous Base: A nucleotide'sidentity is determined by the nitrogenous base, which is a crucial component. Adenine (A), cytosine (C), guanine (G), and thymine (T) are the four different nitrogenous bases that can be found in DNA.

A nucleotide contains a five-carbon sugar molecule as its sugar. The sugar is referred to as deoxyribose in DNA and ribose in RNA. The sugar molecule joins the nitrogenous base to the phosphate group and gives the nucleotide structural stability.

PhosphateGroup: The phosphate group is a nucleotide's third constituent. It is made up of four oxygen atoms joined by a phosphorus atom.

Thus, these are the three components make up nucleotide.

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Like DNA, RNA polymers are make up of chains of nucleotides *. These nucleotides have three parts: 1) a five carbon ribose sugar, 2) a phosphate molecule and 3) one of four nitrogenous bases: adenine, guanine, cytosine or uracil.
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