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3 years ago

If the net force an object at rest is zero the object will remain at rest. True or false

Biology

1 answer:

FromTheMoon [43]3 years ago

4 0

True

Explanation:

If the net force on an object at rest is zero, the object will remain at rest. This is one of the postulates of newton's law of motion.

Newton's first law of motion states that "an object will continue in its state of rest or uniform motion unless if it is acted upon by an external force. "

If no net force acts on a body, it will forever remain at rest.
The force on a body causes its motion and acceleration.
A body will continue in uniform motion if no external force acts on it.

Learn more:

Newton's law brainly.com/question/11411375

#learnwithBrainly

You might be interested in

_______ cause(s) populations to change over time.

vekshin1

The answer is B., Natural Selection.

Weather certainly doesn't change populations, and genes only caused individuals in a population to be slightly ( genetically-wise ) different from the others. It does cause change, but not change in the whole population over time.
Natural disasters don't change the populations over time either. Natural disasters only caused change in their environment, at most.

So, the only answer left is natural selection, and it makes sense too!
Natural selection is the process where the individuals with better traits suited to survive in that specific environment live on and give those good traits to their offspring.
The individuals with less suited traits to survive will die out, and will not be given an opportunity to reproduce and pass on their less suited traits, so over time, the population will increase of individuals with better suited traits to survive and the individuals with less suited traits will eventually die out, therefore making the entire population change.

Hope I helped you!

3 0

3 years ago

Scientists have successfully cloned animals, including mammals such as sheep. Which statement provides the most likely reason th

tigry1 [53]

Answer:

4) Some people consider human genetic experiments

unethical.

Explanation:

1) Humans have DNA that is structurally very different from

other mammals.

2) Cloning can only he performed on animals that normally

reproduce asexually.

3) Human genes are made of too many different types of

simple sugars.

4) Some people consider human genetic experiments

unethical.

The statement that provides the most likely reason that a human has not yet been cloned is that some people consider human genetic experiment unethical.

Option 1 is incorrect because human DNA is similar in structure to other living organisms with components such as a phosphate group, a deoxyribose sugar and purine/pyrimidine bases.

Option 2 is incorrect because cloning is not limited to asexually reproducing organisms only. Sheep, for example, produces only sexually and has been successfully been cloned.

Option 3 is incorrect because human genes, just like every other organisms is consist of DNA with deoxyribose pentose sugar being one of the components. The situation of too many different types of simple sugars doe not arise.

The correct option is 4.

6 0

3 years ago

What causes a star to shine brightly

yuradex [85]

Deep inside the core of the sun, protons can collide into eachother with enough speed that they stick together to form a helium nucleus and generate a big amount of energy at the same time.

8 0

3 years ago

Read 2 more answers

Three linked autosomal loci were studied in smurfs.

cupoosta [38]

Answer:

height -------- color --------- mood

(13.2cM) (14.5cM)

C=0.421

I = 0.579

Explanation:

We have the number of descendants of each phenotype product of the tri-hybrid cross.

Phenotype Number

pink, tall, happy 580

blue, dwarf, gloomy 601

pink, tall, gloomy 113

blue, dwarf, happy 107

blue, tall, happy 8

pink, dwarf, gloomy 6

blue, tall, gloomy 98

pink, dwarf, happy 101

Total number of individuals = 1614 = N

Knowing that the genes are linked, we can calculate genetic distances between them. First, we need to know their order in the chromosome, and to do so, we need to compare the phenotypes of the parental with the ones of the double recombinants. We can recognize the parental in the descendants because their phenotypes are the most frequent, while the double recombinants are the less frequent. So:

Parental)

Pink, tall, happy 580 individuals

Blue, dwarf, gloomy 601 individuals

Simple recombinant)

Pink Tall Gloomy 113 individuals

Blue, Dwarf, Happy 107 individuals

Blue Tall Gloomy 98 individuals

Pink Dwarf Happy 101 individuals

Double Recombinant)

Blue Tall Happy 8 individuals

Pink Dwarf Gloomy 6 individuals

Comparing them we realize that parental and double recombinant individuals differ in the position of the gene codifying for color. They only change in the position of Blue and Pink. This suggests that the position of the color gene is in the middle of the other two genes, height and mood, because in a double recombinant only the central gene changes position in the chromatid.

So, the alphabetic order of the genes is:

---- height ---- color ----- mood ----

Now we will call Region I to the area between Height and Color, and Region II to the area between Color and Mood.

Once established the order of the genes we can calculate distances between them, and we will do it from the central gene to the genes on each side. First We will calculate the recombination frequencies, and we will do it by region. We will call P1 to the recombination frequency between Height and color genes, and P2 to the recombination frequency between color and mood.

P1 = (R + DR) / N

P2 = (R + DR)/ N

Where: R is the number of recombinants in each region (the ones that have an intermediate phenotypic frequency), DR is the number of double recombinants in each region, and N is the total number of individuals. So:

Region I

Tall------ Pink--------happy (Parental) 580 individuals

Dwarf ---Pink------- Happy (Simple Recombinant) 101 individuals

Dwarf--- Pink-------Gloomy (Double Recombinant) 6 individuals

Dwarf----Blue-------Gloomy (Parental) 601 individuals

Tall ------Blue------- Gloomy (Simple Recombinant) 98 individuals

Tall ----- Blue------- Happy (Double Recombinant) 8 individuals

Region II

Tall------ Pink--------happy (Parental) 580 individuals

Tall-------Pink------- Gloomy (Simple Recombinant) 113 individuals

Dwarf----Pink------- Gloomy (Double Recombinant) 6 individuals

Dwarf----Blue-------Gloomy (Parental) 601 individuals

Dwarf ----Blue-------Happy (Simple Recombinant) 107 individuals

Tall ----- Blue------- Happy (Double Recombinant) 8 individuals

In each region, the highlighted traits are the ones that suffered recombination.

P1 = (R + DR) / N

P1 = (101+6+98+8)/1614

P1 = 213/1614

P1 = 0.132

P2= = (R + DR) / N

P2 = (113+6+107+8)/1614

P1 = 234/1614

P1 = 0.145

Now, to calculate the recombination frequency between the two extreme genes, height and mood, we can just perform addition or a sum:

P1 + P2= Pt

0.132 + 0.145 = Pt

0.277=Pt

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 every 100 meiotic products, one results in a recombinant product.

Now we must multiply each recombination frequency by 100 to get the genetic distance in map units:

GD1= P1 x 100 = 0.132 x 100 = 13.2 MU = 13.2 cM

GD2= P2 x 100 = 0.145 x 100 = 14.5 MU = 14.5 cM

GD3=Pt x 100 = 0.277 x 100 = 27.7 MU = 27.7 cM

To calculate the coefficient of coincidence, CC, we must use the next formula:

CC= observed double recombinant frequency/expected double recombinant frequency

Note:

-observed double recombinant frequency=total number of observed double recombinant individuals/total number of individuals

-expected double recombinant frequency: recombination frequency in region I x recombination frequency in region II.

CC= ((6 + 8)/1614)/0.132x0.145

CC=0.008/0.019

CC=0.421

The coefficient of interference, I, is complementary with CC.

I = 1 - CC

I = 1 - 0.421

I = 0.579

8 0

3 years ago

Is sharks and crocodiles closely related

VashaNatasha [74]

Answer:

More recent phylogenetic analyses, based on mitochondrial DNA, have suggested that the crocodile shark is closely related to either the megamouth shark or the sand sharks (Odontaspididae).

8 0

3 years ago