C.elegans is a model organism and was the first eukaryotic organism to have its genome sequenced. The free-living nematode is often used in laboratories investigating nervous system development with all 302 of its neurons and their effectors categorized. Interesting control mechanisms have been investigated with reproduction, particularly with egg-laying in the nematode. There are 16 muscles, 2 types of neurons, and multiple receptors involved in the process of laying eggs in C.elegans, and there are mutations in all of those structures for the study of the process. One particular mutation that prevents the laying of eggs by the worm is rescued by the neurotransmitter, serotonin. That rescue suggests that the mutation is most likely in which of the following?
A. one of the muscles needed for egg-laying
B. a receptor for serotonin on cells needed for egg-laying
C. a pre-synaptic neuron involved in egg-laying
D. a post-synaptic neuron involved in egg-laying

Answer:

C. a pre-synaptic neuron involved in egg-laying

Explanation:

Serotonin (5-HT) is a neurotransmitter, i.e., a molecule that binds to specific receptors and thus transmits signals from one pre-synaptic neuron to another target cell. In humans, serotonin is involved in many physiological functions including sleep, mood, emotions, appetite, digestion, etc. Moreover, Caenorhabditis elegans is a model organism widely used in neuroscience research in order to understand neuromodulation at the level of individual neurons. In C. elegans, serotonin modifies behavior by regulating neuronal excitability and synaptic efficiency. Moreover, also in C. elegans, it has been shown that serotonin induces egg-laying and also provides a feedback regulatory mechanism by inhibiting the activity of the pre-synaptic neurons that release it. In consequence, in this case, it is expected that serotonin rescues the loss of function of serotonin receptors required for egg-laying by providing a regulatory feedback loop that contributes to serotonin adaptation.

(d) A conservation group with a long-term goal of preserving species believes that all at-risk species will disappear whenever land inhabited by those species is developed. It has an opportunity to purchase land in an area about to be developed. The group has a choice of creating one large nature preserve with an area of 45 square kilometers and containing 70 at-risk species, or 5 small nature preserves, each with an area of 3 square kilometers and each containing 16 at-risk species unique to that preserve. Which choice would you recommend and why

whether falling dominoes form a wave and how do you now ​

A scientist is studying an aquarium ecosystem that contains water, plants, and fish that eat those plants. The aquarium
has glass walls so light can get in, but it is sealed so no material can move into or out of the tank. When the scientist
turned the aquarium's light on, carbon dioxide in the water started decreasing. How is carbon moving and what is
happening to the amount of carbon in the living things inside the aquarium? Explain your thinking as completely as
possible

__________mutations can cause the
reading frame to be moved one direction
or the other.
A. Point
B. Inverted
C. Frameshift

how can oil wells affect the environment?

Question 3 of 10
What is the product of meiosis Il?

Which two processes allow water to enter the atmosphere?

evaporation and transpiration
precipitation and condensation
condensation and evaporation
transpiration and precipitation

Which organelle is labeled a

Which of the following is an example of a trade-off?
O A. Selecting a bag that can be recycled over
one that cannot
B. Selecting a bag that produces less waste
over a bag that is more expensive
C. Selecting a bag that takes a lot longer to
break down in a landfill than the alternative
O D. Selecting a bag that produces less waste
over a bag that is more convenient

A scientist investigated DNA replication in two groups of cells, labeled A and B. She injected radioactively labeled nucleotides into cells of each group and allowed DNA replication to begin. When replication was halfway completed, she injected a drug into the cells to stop replication. She then examined the cells to determine the distribution of the newly-synthesized DNA. She found each cell of group A had many segments of new DNA in its nucleus, while each cell of group B had a single segment of new DNA in its cytoplasm.

What can the researcher conclude about the cells?

A.
Group A cells are prokaryotic because they must have many origins of replication.
B.
The cells in group B are prokaryotic because they replicate their DNA in the cytoplasm.
C.
Group B cells are eukaryotic because they must have a single origin of replication.
D.
The cells in group A are eukaryotic because they replicate their DNA in the cytoplasm or nucleus.

When baking an empty pie crust
o poke holes in it
o weigh it down
o both choices

what makes the Earth center act like a magnet

Which plant adaptation is most common in the Deciduous Forest biome?

A.
Leaves change due to changes in climate in the Fall and Spring.

B.
Plants can begin to grow under snow, grow close to the ground, and flower quickly.

C.
Roots that can store a lot of water grow.

D.
Some plants in this biome start growing on leaves due to a lack of sunlight on the ground.

What is the most current theory for the formation of Earth's moon?
arth

how the rabbit population changed over the course of 10 years.

what is the center of a cell called

Which of these does not represent a direct transfer of carbon

1.Air to trees
2.Giraffe to tree
3.Tree to Giraffe

A ___________ is a part of a chromosome that is inherited from the parent(s).

a
virus
b
trait
c
mutation

About how many days pass between a new moon and a 3rd quarter moon?

PLEASE, PLEASE, PLEASE HELP!!! REAL ANSWERS ONLY!!! NO LINKS OR I WILL REPORT!!! NO BOTS EITHER!!!
Respond to the question: How do things move across a cell membrane? Give two examples. (5-8 sentences)
https://www.khanaca demy.org/gclassroom/test-prep/mcat/cells/transport-across-a-cell-membrane/v/how-do-things-move-across-a-cell-membrane
That is the video. Remove the space to make it work.

Inhibition of enzyme X by eutricoline prevents dehydration synthesis reactions
from occurring between DNA nucleotides. Describe the effect this has on the
replication process. Explain why eukaryotic cells treated with eutricoline do not
increase in number over time

Which of these is the most serious impact to an ecosystem after a tornado?

A. an increase in biodiversity

B. soil erosion along with water pollution

C. the growth of plants in newly cleared areas

D. animals relocating to different habitats

cichlids fish evolution, as seen in lake victoria in africa, is an example of ______ equilibrium.

According to the theory of natural selection, some individuals in a population survive while others die.he proposed that survival is due to the

A. Possession of structures developed through use
B. Possession of adaptions suites to the environment
C. Lack of competition within the species
D. Ability to change their genes

WHAT IS WRONG WITH THIS PROBLEM. HELP ASAPPP

Explaining hardy Weinberg equilibrium and the eastern squirrel/ how many in the population have the following genotypes

2
From the thousands that sprout, why will only 1 or 2 healthy
trees grow into the available space between other existing
trees?
Small sprouts will flourish as there is plenty of space on Earth for plants
to grow
Small sprouts will compete for resources as usual, volcanic eruptions do
not effect plants
Small sprouts will never survive in the soil mixed with volcanic dust.
Small sprouts will compete for the remaining space that has adequate
sunlight

Which of the following observations is qualitative and not quantitative?
A. surveying the size of a good population.
B.observing the nocturnal behavior of coyote populations.

C.recording the date when goose migrations begin every year.

D.counting the number of goose nests that are robbed of eggs in an area.

it’s environmental conditions change over time it is most likely a population of organisms in the environment will survive if??? HELP

Can someone please help me!!