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Elis [28]
3 years ago
13

Which of the following correctly describes the first animals that appeared according to science

Biology
1 answer:
IceJOKER [234]3 years ago
7 0
These were soft and boneless creatures I just took the test I hope this helps :D
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SO IS IT A OR B ??????!!!!!!!
maxonik [38]
It depends on what the question is, buddy
5 0
3 years ago
A gene has 2 alleles, R & B, List the possible genotypes? I also need help with questions 5, 6, 7 and 8 please help! Pls loo
irakobra [83]

Answer:

5.) The possible genotypes should be: RR RB BB ( if the could for the same proteins)

6.) Frequency of R: 0.5

7.)Frequency of R: 0.5

8.)Frequency of R: 0.375

Explanation:

5.) If R and B code for the different forms of the same protein then they are only a few possible out comes

6.) First calculate the total alleles in population

allele R= 40

Allele B=40

total allele = R+B= 40+40

=80

Now to find allele R frequency is:

(Total R alleles) / (Total allele in pop)

40/80=

0.5

7.)Calculate the total alleles

Alleles from for R

RR= 10

R=10x 2= 20

Multiply the value by 2 because there are 2 R alleles present in

RB=20

R=20

Number doesn't change there is only 1 R allele

Total R=20+20

=40

Alleles For B

BB=10

B=10×2

=20

Same thing here, two B alleles together so multiple by 2

RB=20

B=20

Total B= 20+20

=40

Total alleles in pop add

40+40

=80

Frequency of R

Total of R/Total Alleles

=40/80

=0.5

8.)Repeat the same thing in 7 but use different numbers

RR=10

R=10x2

=20

RB=10

R=10

Total R= 20+10

=30

5 0
3 years ago
Is the movement of water along the concentration gradient
Nuetrik [128]

Answer:

<em>- Is the movement of water along the concentration gradient: </em><em>Osmosis</em><em>. </em>

<em>- Is the use of energy to move the particles against the concentration gradient: </em><em>Active transport</em><em>. </em>

<em>- Is the movement of particles by diffusion without energy: </em><em>Simple diffusion</em><em>. </em>

<em>- Is the movement of particles along the concentration gradient: </em><em>Passive transport</em><em>.</em>

Explanation:

The mechanisms of cellular transport involve all the processes that the cell carries out to incorporate substances into its interior or send them to the extracellular space, through its semipermeable cell membrane.

<h3>- Osmosis</h3>

Is a type of transport that consists of the passage of water from a space with a lower concentration of solutes to one with a higher concentration, in order to reach equilibrium, following a concentration gradient.

The concentration gradient is given by the difference in concentration between two substances, which indicates the direction in which molecules, such as water, should move from one place to another.

<h3>- Active transport</h3>

Unlike passive transport mechanisms, which depend on a concentration gradient that determines the movement of particles, in active transport there are two characteristics that define it:

The passage of substances into the cell against a concentration gradient.

The use of energy to carry out this process.

In this case, the passage of substances through the cell membrane will be according to the requirements of the cell, or when they cannot pass through the membrane.

<h3>- Simple diffusion</h3>

According to the characteristics of the cell membrane, some substances can pass freely through it while others require special mechanisms. When a molecule is able to pass through the membrane without the use of special mechanisms or energy we speak of simple diffusion.

In a cell membrane, whose composition is by hydrophobic or non-polar lipid molecules, simple diffusion allows the passage of non-polar molecules, gases and alcohol.

<h3>- Passive transport</h3>

Refers to the mechanism of entry and exit of substances from the cell that does not require the use of energy.

The mechanisms involved in the passive transport of the cell are simple diffusion, osmosis, facilitated diffusion - which requires special conveyors or channels - and ultrafiltration, which depends on hydrostatic pressure. Examples of substances using this mechanism are lipid molecules, water and electrolytes.

Learn more:

Lipidic bilayer and cellular transport brainly.com/question/6955159

3 0
3 years ago
A scientist discovers a new organism that is related to clownfish. What can the scientist discover by using molecular clocks?
Sergeu [11.5K]
The amount of time that the 2 species have been evolving apart??
5 0
3 years ago
Read 2 more answers
7. A type of cell division that results in diploid cells: [meiosis / mitosis
White raven [17]

Answer:mitosis produces 2 diploid cells

Explanation:

4 0
3 years ago
Read 2 more answers
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