1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
mrs_skeptik [129]
3 years ago
6

A spherical bacterial cell has a radius of 3 pm. The human egg cell has a radius of 100 pm.

Biology
1 answer:
lara [203]3 years ago
7 0

Answer:

<u>The bacterial cell because it has the largest surface-to-volume-ratio.</u>

Explanation:

The rate of diffusion in and out of a body depends on surface area to volume ratio. The higher the ratio the greater the rate of diffusion and the lower the ratio, the lower the rate of diffusion.

This implies that small organisms like the bacteria cell expose a large surface area to the surrounding when compared to big organism cells. Therefore, small organisms depend on diffusion as a means of transport of foods, respiratory gases and waste products.

Large organisms, in addition to diffusion have trasnport systems to increase the efficiency of diffusion.

You might be interested in
Antibodies:
alex41 [277]
A) remain in the body after production
B) flag antigens for destruction
C) are an important part of the immune system
D) all of the above

D) ALL ARE CORRECT!!
4 0
3 years ago
A scientist uses materials in her lab to cut a DNA sample into fragments. What process is this called?
Studentka2010 [4]

The right answer is The digestion of DNA by restriction enzymes.

The fragmentation of the DNA is done by bacterial enzymes called restriction enzymes.

Restriction-enzymes (or endonucleases) recognize and cut the DNA into a specific sequence. These enzymes are naturally produced in bacteria as a defense against bacteriophages - viruses that infect bacteria. The bacterial restriction enzymes cut the DNA of the invasive bacteriophage while leaving the bacterial genomic DNA healthy and safe through the addition of methyl groups.

These enzymes are used in practice at the laboratory level to explore DNA.

7 0
3 years ago
Read 2 more answers
Which subdivision of anatomy involves the study of organs that function together?
zloy xaker [14]
It is the macroscopic anatomy with a systemic approach.
There are two levels of the human body: macroscopic (gross anatomy) and microscopic level. For each of the two levels, there is a separate subdivision of anatomy.
There are two approaches for gross anatomy:
1. Regional approach-human body is divided into regions like arm, forearm, wrist etc. Structures within that region are studied simultaneously.
<span>2. Systemic approach-the body is divided into organ systems like skeletal system, or nervous system and structures belonging to one system are studied together.</span>
3 0
3 years ago
Check all statements that are true about nuclear radiation.
Darya [45]

Answer:

All these are true statements.

Alpha radiation is a helium nucleus.

Beta radiation can be stopped by thick wood or a sheet of aluminum.

electrons are beta radiation.

Alpha radiation is easily stopped by paper or clothing.

Explanation:

Alpha beta and gamma radiations are the examples of ionizing radiations. When an atom is an excited state and having high energy, the atom is in unstable state. The excess of energy is released by the atom to get the stability. The released energy is in the form of radiations which may include alpha, beta, gamma, X-ray etc.

Beta radiations:

Beta radiations are result from the beta decay in which electron is ejected. The neutron inside of the nucleus converted into the proton an thus emit the electron which is called β particle.

The mass of beta particle is smaller than the alpha particles.

They can travel in air in few meter distance.

These radiations can penetrate into the human skin.

The sheet of aluminium is used to block the beta radiation

⁴₆C → ¹⁴₇N + ⁰₋₁e

The beta radiations are emitted in this reaction. The one electron is ejected and neutron is converted into proton.

Properties of alpha radiation:

Alpha radiations are emitted as a result of radioactive decay. The atom emit the alpha particles consist of two proton and two neutrons. Which is also called helium nuclei. When atom undergoes the alpha emission the original atom convert into the atom having mass number less than 4  and atomic number less than 2 as compared to parent atom the starting atom.

Alpha radiations can travel in a short distance.

These radiations can not penetrate into the skin or clothes.

These radiations can be harmful for the human if these are inhaled.

These radiations can be stopped by a piece of paper.

₉₂U²³⁸   →   ₉₀Th²³⁴  + ₂He⁴  + energy

Gamma radiations:

Gamma radiations are high energy radiations having no mass.

These radiations are travel at the speed of light.

Gamma radiations can penetrate into the many materials.

These radiations are also used to treat the cancer.

Lead is used for the protection  against gamma radiations because of its high molecular density.

The lead apron are used by the person when treated with gamma radiations.

Lead shields are also used in the wall, windows and doors of the room where gamma radiations are treated, in-order to protect the surroundings.

False statements:

Gamma radiation is an electron (false)

Gamma radiation can be stopped by clothing, (False)

Alpha radiation is a high energy electromagnetic wave (False)

Stable and non-stable nuclei can give off radiation. (false)

only unstable nuclei give off radiations to get stability.

8 0
4 years ago
Organisms composed of fungi and algae are called
Temka [501]
<span>Lichen is your answer

</span>
5 0
4 years ago
Read 2 more answers
Other questions:
  • Explain Newton’s 1st Law of Motion and give an example.
    5·2 answers
  • When you notice that someone has unusually blue eyes, you've noticed their
    5·2 answers
  • What is the sugar in deoxyribonucleic acid (DNA)?
    6·2 answers
  • Natural depression on the earths surface
    15·1 answer
  • How does oxygen concentration affect the fish that live in the pond
    6·1 answer
  • Organic sediment on lake bottoms and the ocean floor is broken down by microbes into inorganic forms of phosphorus in a process
    7·2 answers
  • Stickleback fish exhibit variation in a morphological trait known as gill rakers. Fish with long gill rakers are very good at ea
    10·1 answer
  • Very young children tend to breathe predominantly with their diaphragm because: Select one: a. their chest wall and ribs are ver
    6·1 answer
  • Which of the following living things has a prokaryote type cell?
    12·2 answers
  • Two different species of single-celled Eukaryotes conduct Cellular Respiration. The first species lives in an oxygenated environ
    5·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!