All categories

3 years ago

The Precambrian time period is segmented into very few parts because:

Biology

2 answers:

SashulF [63]3 years ago

6 0

the correct answer is a

konstantin123 [22]3 years ago

6 0

Answer:

A. the fossil record is scarce

Explanation:

The precambrian is the eon that encompasses more years on Earth and ended 542 million years ago.

During those years, most of the life on Earth was single-celled or soft-bodied in the case of being multicellular.

From there, numerous orogenic changes have occurred on the planet and due to this and the lack of hard structures in organisms, the probability of fossil generation is minimal.

You might be interested in

________ is a hormone that is released from the ________ to stimulate the production of red blood cells.

Alisiya [41]

Erythropoietin is a hormone that is released from the kidneys to stimulate the production of red blood cells.

8 0

4 years ago

Bob, a nutritionist who works for the university medical center, has been asked to prepare special diets for two patients, susan

abruzzese [7]

Answer and Explanation:

Possibly, you forgot to attach the table with the contents of each food. Therefore, I calculated the task with similar values.

1. Assume you have Food A, B, and C. Each has certain amount of Calcium, Iron, and Vit C.

Let's designate: Calcium → X oz , Iron → Y oz, vit C → Z oz

2. Assume you have following amount of Calcium in each food:

Food A = 30 mg/oz
Food B = 25 mg/oz
Food C = 20 mg/oz

3. Assume you have following amount of Iron in each food:

Food A = 1 mg/oz
Food B = 1 mg/oz
Food C = 2 mg/oz

4. Assume you have following amount of vit C in each food:

Food A = 2 mg/oz
Food B = 5 mg/oz
Food C = 4 mg/oz

Calculations:

→ You have 3 different food and each has Calcium in it. You need exactly 320mg of Calcium per day. Therefore, each food would comprise certain proportion of daily Calcium intake. We can come up with equation: 30X+25Y+20Z = 390 mg

Similarly, for iron and vitamin C, the next equations could be used:

X+Y+2Z=17 - Iron

2X+5Y+4Z=42 - Vit C

→ Now you have a system of equations:

30X+25Y+20Z = 390 (1)

X+Y+2Z=17 (2)

2X+5Y+4Z=42 (3)

→ Look for similarities! (1) and (3) seem to be similar. We can multiply the (3) by -5 to obtain: -10X-25Y-20Z=-210. We add the (1) and modified (3) equations.

30X+25Y+20Z = 390

-10X-25Y-20Z=-210

__________________

20X+0+0=180

20X=180

→ X=9 (oz of Calcium)

→ Now, we can put x=9 into equations above to ease our job:

270+25Y+20Z=390 → 25Y+20Z=390-270=120

9+Y+Z=17 → Y+2Z=17-9=8

18+5Y+4Z=42 → 5Y+4Z=42-18=24

→ Similarly, we can use Eq-s (2) and (3). We can multiply the (2) by -5 to obtain: -5Y-10Z=-40. We add the (3) and modified (2) equations.

-5Y-10Z=-40

5Y+4Z=24

__________________

-6Z=-24

Z=4

→ Z=4 (oz of vit C)

→ Now, we can take X+Y+Z=17 (2) and just put in known values(X=9 and Z=4) to obtain Y:

9+Y+4=17

→ Y=17-9-4=4 (oz of Iron)

That's all! So, if you have table values, you can just re-write the equations and doing it stepwise, as it is shown here, you can manage to calculate every value you need :)

3 0

3 years ago

Compare and contrast cell differentiation in plant and animal cells

balandron [24]

The cells are generally the same but animal cells don't have a cell wall and also there vacuole is smaller than plants

6 0

3 years ago

Sound waves can only travel through fluids TRUE or FALSE

Brrunno [24]

Answer:

false

Explanation:

Sound waves need to travel through a medium such as a solid, liquid, or gas. The sound waves move through each of these mediums by vibrating the molecules in the matter. The molecules in solids are packed very tightly. Liquids are not packed as tightly as solids. And gases are very loosely packed.

6 0

4 years ago

Read 2 more answers

White skin a recessive trait, So if a white person had children with a black person, would ALL of their children be black? No ma

My name is Ann [436]

If a white person had children with a black person, not all of their children would be black, but majority of them would. There is a 75% chance each time the parents have an offspring that the child will be black. It would not matter if the black person was the mother or the father, because either way they are the dominant trait, and according to the punnet square, that is all that matters and that will effect the outcome.

8 0

4 years ago