All categories

2 years ago

A common element among all the river valley civilizations was:

Biology

2 answers:

Free_Kalibri [48]2 years ago

8 0

Answer:

A common element among all the river valley civilizations was irrigation systems that moved water to crops and settlements

Explanation:

River Valley civilizations where the civilizations that were found on the banks of the river like the Mesopotamia ,Indus valley civilization.

These civilization where agriculture based civilization as they depended on river for drinking water and irrigational activities

slega [8]2 years ago

3 0

Answer:

Explanation:

Answer:

A common element among all the river valley civilizations was irrigation systems that moved water to crops and settlements

Explanation:

River Valley civilizations where the civilizations that were found on the banks of the river like Mesopotamia, Indus valley civilization.

This civilization where agriculture-based

based civilization as they depended on river for drinking water and irrigational activities

You might be interested in

Which of these elements is likely to be found in an organic compound?

Anettt [7]

Answer:

it could be B or A

Explanation:

hope it helps

5 0

2 years ago

4) A homozygous groucho fly ( gro, bristles clumped above the eyes) is crossed with a homozygous rough fly (ro, eye abnormality)

docker41 [41]

Answer and Explanation:

A homozygous groucho fly ( gro, bristles clumped above the eyes) is crossed with a homozygous rough fly (ro, eye abnormality).

The F1 females are testcrossed, producing these offspring: groucho 518 rough 471 groucho, rough 6 wild-type 5 1000 a) What is the linkage distance between the two genes? B) Plot the genes on a map c) If the genes were unlinked and the F1 females were mated with the F1 males, what would be the offspring in the F2 generation?

1st cross:

Parental) grogro ro+ro+ x gro+gro+ roro

F1) gro+gro ro+ro

2nd cross:

Parental) gro+gro ro+ro x grogro roro

Gametes) gro+ro+ gro ro

gro+ro gro ro

gro ro+ gro ro

gro ro gro ro

Punnet square)

gro+ro+ gro+ro gro ro+ gro ro

gro ro gro+gro ro+ro gro+gro roro grogro ro+ro grogro roro

F2)

0.518 grogro ro+ro (518 individuals)

0.471 gro+gro roro (471 individuals)

0.006 grogro roro (6 individuals)

0.005 gro+gro ro+ro (5 individuals)

Total number of individuals 1000

Note: These frequencies were calculated dividing the number of individuals belonging to each genotype by the total number of individuals in the F2.

To know if two genes are linked, we must observe the progeny distribution. If individuals, whos genes assort independently, are test crossed, they produce a progeny with equal phenotypic frequencies 1:1:1:1. If we observe a different distribution, that is that phenotypes appear in different proportions, we can assume that genes are linked in the double heterozygote parent.

In the exposed example we might verify which are the recombinant gametes produced by the F1 di-hybrid, and we can recognize them by looking at the phenotypes with lower frequencies in the progeny.

By performing this cross we know that the phenotypes with lower frequencies in the progeny are groucho, rough and wild-type. So the recombinant gametes are gro+ro+ and gro ro, while the parental gametes are gro+ro and gro ro+.

So, the genotype, in linked gene format, of the double heterozygote individual in the F1 is gro+ro/gro ro+.

To calculate the recombination frequency we will make use of the next formula: P = Recombinant number / Total of individuals. The genetic distance will result from multiplying that frequency by 100 and expressing it in map units (MU). One centiMorgan (cM) equals one map unit (MU).

The map unit is the distance between the pair of genes for which one of every 100 meiotic products results in a recombinant product.

The recombination frequency is:

P = Recombinant number / Total of individuals

P = 6 + 5 / 1000

P = 11 / 1000

P = 0.011

The genetic distance between genes, is 0.011 x 100= 1.1 MU.

Genetic Linkage Map:

Parental Phenotypes)

-----gro+------ro---- -----gro------ro+----

----- gro ------ro---- ---- gro------ ro ----

Recombinant phenotypes)

-----gro+------ro+---- -----gro------ro----

----- gro ------ ro---- -----gro------ro----

If the genes were unlinked and the F1 females were mated with the F1 males, the offspring in the F2 generation would have been

4/16 = 1/4 gro+gro ro+ro

4/16 = 1/4 gro+gro roro

4/16 = 1/4 grogro ro+ro

4/16 = 1/4 grogro roro

Their phenotypic frequencies would be 1:1:1:1 related.

7 0

2 years ago

How many bacterium can fit into an animal cell

Bingel [31]

As much that can fit.

3 0

2 years ago

A reflex arc consists of

s2008m [1.1K]

Answer:

All of the above.

Explanation:

Reflex arc may be defined as the neural pathway that control the function of the reflex system of the body. Two main types of reflex arc are somatic reflex arc and autonomic reflex arc.

The afferent neuron carries signal from the receptors to the integrating center via the interneuron. The efferent neuron carries signal from the integrating center to the effector organ via the inter neuron.

Thus, the correct answer is option (e).

3 0

3 years ago

The weather map shows air pressures in millibars.

dmitriy555 [2]

The weather map shows air pressures in millibars. 1008 1004 1.004 1008 21004 1008 1004 Logs -1000 1000 1000T 1-004 19.00 1000 2008 996 T004 2004. 2004 1008 Which set of conditions best describes the weather at the area of lowest air pressure? O A.) Bright sun with no wind O B.) Partly cloudy with no wind O C.) Mostly sunny with light winds O D.) Overcast skies with strong winds - did not match any image results.

Suggestions:

Make sure all words are spelled correctly.
Try different keywords.
Try more general keywords.
Try fewer keywords.

6 0

2 years ago