An atom with an equal number of electrons and protons has no _____

An atom with an equal number of electrons and protons has no charge.

a scientist is comparing the outer layer of an onion cell to the outer layer of a human skin cell. what is unique about the outer layer of the onion cell compared to the skin cell?
a. it contains proteins.
b. it contains cellulose.
c. it contains carbohydrates.
d. it is selectively permeable.

Which organism diverged first?? *
Birds
Sharks
Rabbits
Primates

Check each of the following statements that are true with regard to Griffith’s experiments.a. ______ Griffith discovered transformation in bacteria.b. ______ Mice injected with smooth bacteria quickly became sick and died.c. ______ Encapsulated bacteria can become "naked" bacteria.d. ______ Bacteria that do not have capsules tend to be harmless.e. ______ Smooth bacteria develop a capsule only after exposure to the DNA of encapsulated (rough) bacteria.f. ______ Griffith’s transforming factor was the protein in the capsule.g. ______ Transformation allows bacteria to acquire new genes.h. ______ Enzymes that destroyed DNA would prevent transformation.

Which scientist devised tests that helped confirm that bacteria and other microorganisms cause a variety of diseases?
Robert Koch
Anton van Leeuwenhoek
Louis Pasteur
Alexander Fleming

1.La energía es la capacidad de un cuerpo para producir trabajo.

2.La energía se clasifica solamente en renovables.

3.Las ondas se pueden propagar en un medio o un espacio vacío.

4. Las ondas se pueden clasificar en longitudinales y transversales.

5. La energía cinética es aquella que se encuentra en movimiento.

6. El núcleo de la Tierra está formado
por metales, principalmente hierro y níquel, y en menor
cantidad por azufre y oxígeno.

7. La corteza terrestre está compuesta por rocas
8. La contaminación se puede
definir como la presencia o acumulación de sustancias en el medio ambiente
que afectan negativamente el entorno.

9. Los elementos de la tabla periódica se clasifican de acuerdo con sus propiedades y características
similares.

II. Escoge

1. Son fuentes de energías renovables:

2. Son fuentes de energías no renovables:

3. Partes de las ondas:
15. La ciencia que estudia los seres vivos es:

16. En la biotecnología se incluyen las áreas de:

17. Consiste en la liberación de sustancias químicas a la atmósfera que alteran su composición.

18. Se debe a la presencia de desechos en el agua. La contaminación de mares, ríos y lagos se produce por
las actividades del ser humano.

19. Se debe a la acción humana (los residuos y la basura arrojada en cualquier superficie terrestre).

20. Cuando el contaminante es una sustancia química que procede normalmente de los usos industriales.

21. Surge con la emisión de fluidos a elevadascontaminación.

22. La actividad humana produce mucho ruido, y los altos decibelios en un determinado lugar por encima de sus niveles naturales marcan la contaminacion.​

Where would you be likely to find the alpine tundra biome?
a. the Russian north woods
b. central plains of the United States
c. the southern most tip of Australia
d. a mountain range in Europe

Question 5
How do increases in the carrying capacity of Earth for people affect the carrying capacity of Earth for other species?
Select one:

It increases for most species.

It decreases for all species.

It decreases for most species.

It increases for all species.

In a swimming pool or lake, the water is a
liquid until the water temperature gets
down to 0 C or 32. F. Water in pools
stays liquid during Las Vegas winters,
with just a bit of ice forming if it gets really cold overnight. Even when it is
chilly in January and February (usually 15° C or 60° F), water stays liquid.
Then, when our area's temperature gets really hot in the summer (usually
about 40° C or 100. F), the water in the pool is still a liquid. It would have
to be 100. C or 212. F for the water in the pool to boil! Those
temperatures have never happened on Earth.
Remember, though, that water does not have to boil to turn to a gas.
Some of the water evaporates at all temperatures. Water temperature is a
measure of the average kinetic energy of its molecules. Some molecules
have more kinetic energy than others. The molecules that have enough
kinetic energy to break the bonds with other molecules can leave the
liquid and move off into the air. That is why you have to keep filling up the
swimming pool, even though it is not boiling.
Why does water stay liquid over a large range of temperatures? Hint:
Think about molecular structure.

Oil pollution in the ocean is mostly caused by

The MAP kinase pathway is activated by ligand binding to a transmembrane receptor, which switches Ras on via GEF (Guanine nucleotide Exchange Factor) that counteracts GAP (GTPase Activating Protein) activity. Ras-GTP in turn activates the downstream signaling intermediates (kinases), which are activated by sequential phosphorylation. Which drug CANNOT be used to target cancer cells that have elevated receptor activation

Space exploration can lead to money going to U.S.
businesses and universities.
What are two things NASA might hire U.S. businesses and universities to do?
A. Teach people to read
B. Improve athletic teams
C. Build complex equipment
D. Research new ideas

_____ is essential for all life within
an ecosystem.
A. Trophic
B. Water cycle
C. Predation

The color of a mineral when it is powdered is called the streak of the mineral. Several minerals have a black streak and make it difficult to identify the mineral with the streak test alone. But a red-brown streak is not very common. We would expect ________ to produce a red-brown streak. A) graphite B) hematite EliminateC) magnitite D) pyrite

A group of students burned three different kinds of food and
collected data.
Food
sample
Mass
Starting
temp.
Ending
temp.
1
100 g
20°C
24°C
2
50 g
20°C
30°C
3
110 g
20°C
27°C
6a. How many calories were contained in each piece of food? Remember:
cal = m XAT

Choose the option that best matches the description given.

the study of the frequency, distribution, cause, and control of disorders in populations:

which best describes the concept of natural selection?

A. an organism will always mutate to survive
B. The fittest organisms are selected for
C. Nature selects the organisms with the most Mutations
D. mutations make organisms more fit

Which of the following is NOT part of a chromosome?
A. genes
B. cells
C. nitrogen bases
D. DNA

I WILL GIVE BRAINLIEST AND EVERYTHING IF YOU HELP ME

In order to go through Mitosis, DNA is packaged into structures known as what.


a

Enzymes

b

Chromosomes

c

Double Helix strands

d

Nucleic Strands

Protein Synthesis and Codons Practice
DNA → T T C A A T G G T C T A G G G

RNA →

Amino Acids →

why are minerals important for our body? describe the 2 groups of minerals
​

difference between antigens and antibodies?​

In DNA, a sequence of three bases is a code for the placement
of a certain amino acid in a protein chain. The table shows some
amino acids with their abbreviations and DNA codes.
Which amino acid chain would be produced by the DNA base
sequence below?
C-A-A-G - T- T - A-A-A-T - T-A

(HELP IM CLUELESS) Biodiversity
542 500
450 400 350 360 250 200 150 160 60
Millions of years ago
Examine the graph that shows the changes in biodiversity over the past 500 million years. Analyze the graph at each of the yellow
triangles. Select the options below that correspond to the events occurring at the yellow triangles. Select ALL that apply.
A)
B)
C)
The change in biodiversity was most stable at the times indicated by the
yellow triangles.
There have been five mass extinction events, with the earliest occurring at
450 million years ago.
Species were evolving faster than the extinction rates, resulting in new
species forming quickly over time.
Humans were altering the environment too quickly with deforestation and
climate change, resulting in many lost species in a short period of time.
The environment was changing faster than the species were adapted at the
time points labeled by the yellow triangles, resulting in a loss of species.
D)
E)

2. Write one question that a
scientific experiment could
answer.

What happens to excess fatty acids and glycerol in the body?​

long time no see?? apple sauce

In the United States, there has been an increase in the number of people infected by mosquito spread diseases that were previously found only in countries
south of the United States. Scientists want to investigate the cause of the increase in mosquito-bome diseases. Scientists have predicted that the mosquitos
carrying disease have moved further north as global temperatures have increased. Which information would be most useful to their investigation?
O A. Meteorologists' annual temperatures of all the major cities in the US for the last ten years.
O B. Population data from the CDC that ranges over several years for mosquitoes that spread disease.
o
C. A report from the Center for Disease Control (CDC) of mosquito spread diseases and their symptoms.
OD. A collection of test results for different vaccines used to prevent mosquito carriab diseases.

What is accomplished during meiosis 1

HELP ASAP
Which of the following is an example of homeostasis?
Q. During a time of high stress, Justin's heart races, his muscles tense, and he feels
sweat dripping down his forehead.
R. Sick with the flu, Alison's body temperature rises to fever levels.
S. Boris doesn't drink very much water one day. To compensate his kidneys remove less
fluid from his blood, and produce less urine than normal.
T. As Grace races up the ten flights of stairs to her apartment, the muscle cells in her
legs produce excess lactic acid, causing a burning sensation in her legs.

1. the north polar constellation can be seen in the southern hemisphere.

true or false

2. the south polar constellation can be seen in the northern hemisphere.

true or false​