Question

Living organisms and non-living systems have numerous characteristics in common, but only organisms -
A have the ability to move
B are composed of cells
C have the ability to self-replicate
D have the ability to utilize energy
E are composed of atoms
This question was asked already but didn't have an actual answer, so anyone who can help me out please do!!

Answer 1

I think it's D because non-living systems can't utilize energy for actual movement. I'm not entirely sure that's the right answer, though.

Answer 2

haha i might just have to take the chance and put D because i cant figure it out either.

Answer 3

It's not D.

Answer 4

We're looking for the one choice that could ONLY apply to living things.

D isn't true because there are non-living things that actually can utilize energy.
Light bulbs, for example. That's electrical energy, right there.

There's a much better choice on that list, that could only apply to living things.

Answer 5

Oh I think I know what it is now... I totally forgot one key concept :P

Answer 6

Yeah you probably know which one it is now.

Answer 7

@downhilladdict

What about you? Still need help?

Answer 8

yes :( @InYourHead

Answer 9

is it E?

Answer 10

We'll eliminate one choice at a a time.

You wanna start with E? Made of atoms?

Do you know what is made of atoms?

Answer 11

Everything.

Answer 12

Everything in our world is made of atoms.

Make sense?

Answer 13

Now....if EVERYTHING in our world is made of atoms....then could option E apply only to living things?

Answer 14

if we go by eliminating options a d and e is eliminated. B and C creates the confusion

Answer 15

I'll explain that in a little while.

Answer 16

Are cars made of atoms?

Answer 17

Remember, I DID say "everything."

Cars ARE made of atoms.
The metal that we use, to build cars, is made of atoms.

Are cars living? Are they alive?

Answer 18

is it cells?

Answer 19

Is it?

shrutipande9 made a good point.

After we eliminate all the choices, then it could be B or C.

Answer 20

This is a tricky question. B or C?

If you know the answer, then you'll probably do better on your next test or homework assignment.

You want me to explain?

Answer 21

If you wouldnt mind.

Answer 22

No I wouldn't mind.

B. made of cells.
C. ability to self replicate.

Which one could ONLY apply to living things?

-----------

Let's talk about C.
The ability to replicate.

Have you learned about mitosis yet?
You know that DNA can copy itself, right?

Answer 23

yes and yes.

Answer 24

Well, DNA can copy itself.

But it isn't ALIVE.

DNA is a type of molecule.
It belongs to living things.

But the smallest unit of life...is a cell.

The smallest thing, in the world, that could be considered living, is a cell.
And DNA is smaller than a cell.

Answer 25

So, choice C CANNOT be applied only to living things.

That leaves us with B.
And a very true fact: ONLY living things can be made of cells.

A cell is a unit of life.
So there's no non-living thing that could be made of cells.

Answer 26

Okay, I get it now. Very helpful thank you. I'm glad you actually explained the answer to me!

Answer 27

I'm glad you wanted to hear an explanation. That way I actually feel that I've helped.

No problem too.

Answer 28

@InYourHead you have an amazing ability to explain a point efficiently. but i have a doubt how can non living systems be self replicating? if u could give an eg?

Answer 29

Eggs are living actually. They're a type of cell.

An exception would be the type of unfertilized eggs that we eat for breakfast. I'm pretty sure they're non-living.

Answer 30

Sorry, am I missing your point?

The thing is...not ALL non-living things can self replicate.
Only some can.

But it's enough so that C wouldn't be the answer we're looking for here. You know?

Answer 31

now the options come down to B and C right. so why is it exactly c and not b. like u said nonliving sys do consume energy eg bulbs. so do u have any eg of self replicating non living systems.

Answer 32

The answer was B, actually.

I didn't explicitly say that it was B, in my explanation.
But I did say that only living things can be made of cells.

I hope that was clear.

@downhilladdict
Did you understand that I was trying to say B is the answer?

Answer 33

haha yes, i fully understand why the answer is B.

Answer 34

Okay good.

Answer 35

I did use an example of something non-living, that can self replicate. That was DNA.

Viruses can also self replicate.

There are some scientists out there who might argue that viruses ARE alive.

But to me, and others, viruses are non-living.
They don't meet all the requirements for life.

Answer 36

He's asking for an example of something non living that self replicates. and you said DNA, its non living and replicates itself, right?

Answer 37

Yes.

Answer 38

oh, see there it is. @shrutipande9

Answer 39

i am convinced. ty @InYourHead
@downhilladdict i am she not he...:-P

Answer 40

ha whoops!

Answer 41

No problem.

Answer 42

i am sorry i may sound very annoying. but after we discussed this ques a whole set of new ques emerged in my mind. firstly can we consider dna as non living? next dna requires a whole set of enzyme machinery to replicate. it cannot do this on its own. so obviously when it is inside the cell or externally provided with the enzymes then only it can replicate.

Answer 43

No you're right. DNA can't strictly replicate on its own.

Truth be told, I can't think of anything that can replicate itself, without the help of something else.

If we're gonna look so deeply, then I can't think of anything that could "self replicate," really. I honestly thought of the same thing, last night.

---------

When we consider living things, we have to look at the criteria for life.

The first point tells us that "living things are made of cells."

And when we look at the definition of "cell,"
we see that it's " the basic structural, functional and biological unit of life."

A cell is also "the smallest unit of life."

What that means is that cells are the smallest level of organization where life begins.

Here are the levels of organization, from smallest to largest:

>Atom
>>Molecule
>>>Cell
>>>>Tissue
>>>>>Organ
>>>>>>System
>>>>>>>Organism

You see, atoms and molecules are smaller than cells.
That's why they can't be considered living.

DNA is a type of molecule.

Answer 44

I m convinced about the cell part. So now we have 2 correct answers for this ques. I also tried to think of a self replicating structure but could not find anything. @inyourhead ty for answering that.

Answer 45

Which two correct answers do you mean?

Answer 46

Made up of cells and self replicating

Answer 47

Well we were looking for the answer that could ONLY apply to living things.

If we consider that DNA needs all of its enzymes to replicate,
then we can strictly say that DNA can't replicate on its own.

Now, if living things COULD self replicate,
then cells would certainly be able to self replicate.

But here's the thing:
cells cannot replicate until DNA has replicated itself.

And if DNA cannot self replicate,
then cells can't strictly self replicate either.
They would also depend on all the enzymes and reactions that DNA needs.

Answer 48

Honestly I do think that the best answer for this question would be B.
That only living things are made of cells.

When we look at C, it gets pretty deep.

If we accept the existence of self-replication,
then we can say that self replication can happen for both living and non-living things.

But if we look deeper, at all the proteins and chemical reactions,
then we might say that NOTHING has the ability to TRULY self replicate.
And that in order to replicate, everything depends on something else.