Complete question:
In Drosophila the anterior-posterior axis is established by
a. The distribution of the RNA-binding transcription factor called bicoid and the protein nanos localized in the anterior and posterior poles of the embryo, respectively
b. The distribution of a gene that codes for an RNA-binding protein called nanos localized in the anterior pole of the embryo and a transcription factor called bicoid localized in the posterior pole of the embryo
c. The distribution of a gene that codes for an RNA-binding protein called nanos localized in the posterior pole of the embryo and a transcription factor called bicoid localized in the anteror pole of the embryo
d. The distribution of the RNA-binding transcription factor called bicoid and the protein nanos localized in the posterior and anterior poles of the embryo, respectively
Answer:
c. The distribution of a gene that codes for an RNA-binding protein called nanos localized in the posterior pole of the embryo and a transcription factor called bicoid localized in the anterior pole of the embryo
Explanation:
When the Drosophila zygote develops, it goes through different stages until it gets to the blastula stage. At this point, there are pole cells that determine the axis of the organism -the anteroposterior and the dorsoventral axis-.
A two hours old embryo has already determined its two axes. A ten hours old embryo has already determined its body segments. And from there, each of them develops a structure that turns to be their identity.
Different genes determine the polarity of the egg.
Dorsoventral genes place in the superior and inferior parts of the egg and determine the development of dorsal and ventral tissues.
The same happens with anteroposterior genes.
The BICOID genes place in the anterior part of the egg and activate the hunchback genes that determine the development of the head and the thorax. The Bicoid mRNA distributes in the anterior region of the egg.The NANOS gene reprimes the hunchback genes, which promoted the development of the posterior structures of the body. The Nano mRNA places in the posterior region of the egg, and Nano proteins distribute in this area.The polarity genes of the egg are genes of maternal effects.
While the bicoid and nano genes are expressed in the ovary, the hunchback gene is expressed in the embryo. This last one is activated or inhibited by the foreign ones.
Bicoid and nano genes gradient regulate the expression of the gap, pair-rule, and segment polarity genes.
Consider the following alleles: X1, X2, X3. The different alleles encode enzymes with slightly different ratesof reaction, but are otherwise identical. Consider a population that is sampled for these alleles at two different times. Below are the genotypes for each individual in this population at time 1. For the Time 1 population calculate the allele frequencies and genotype frequencies.(4points)
Complete question:
Consider the following alleles: X1, X2, X3. The different alleles encode enzymes with slightly different rates of reaction, but are otherwise identical. Consider a population that is sampled for these alleles at two different times. Below are the genotypes for each individual in this population at time 1. For the Time 1 population calculate the allele frequencies and genotype frequencies.(4points)
Time 1: Genotypes for each individual in this population
1XX1, X1X2, X2X2, X2X3, X2X2, X2X2, X1X3, X2X2, X1X1, X2X2, X3X3, X2X3, X2X3, X2X3, X2X3, X1X3, X1X1, X1X2, X1X3, X1X2, X1X2, X1X3, X1X1, X2X1, X1X1, X1X3, X3X3, X2X2, X3X3, X2X2
Answer:
allelic frequencies
• p = 0.34
• q = 0.4
• r = 0.27
genotypic frequencies
• X1X1 = 0.17
• X1X2 = 0.17
• X1X3 = 0.17
• X2X2 = 0.23
• X2X3 = 0.17
• X3X3 = 0.1
Explanation:
Due to technical problems, you will find the complete explanation in the attached files
Which of the following is *true* of the placenta? Question 18 options: 1) It fully develops six months after birth. 2) It forms during the seventh month of prenatal development. 3) It is the fluid-filled sac that houses the developing embryo and fetus. 4) It allows the exchange of nutrients between the embryo and the mother, while at the same time filtering out harmful material.
Answer:
4) It allows the exchange of nutrients between the embryo and the mother, while at the same time filtering out harmful material.
Explanation:
The placenta is an organ present in all mammals. She is confirmed between the 6th and 8th week of pregnancy and has as main function the exchange of substances between the mother and the fetus. Among these substances are nutrients, gases and even secretions. The placenta also has the function of fighting infections and promoting immunity to the fetus, in addition, it can act as the lung, the intestine and the liver, while the fetus does not develop its organs.
Use the information and model to answer the following question.
Answer:
The Answer is A...............
can somebody please help me? :)
Determine the conditions when a long tail would be an adaptation
Which of the following is NOT a rapid (fast) change in Earth's surface? *
1 point
landslides
volcanoes
deltas
earthquakes
HELPPPPP PLZ NEED IT BY TODAY PLLZZZZZZ 10 PIONTS
Answer:
delta
Explanation:
deltas take time to cause changes in the earth's surface as it takes time for water to erode and change things. volcanoes takes minutes to burn and ruin anything in its path, and landslides destroys everything in its path as well immediately.
A rapid or fast change can be defined as one that occurs quickly within a short amount of time.
Among the given example of changes, the types of changes are as follows:
Landslides - It is a result of imperceptive downslope movement and can occur within 10 seconds.Volcanoes - The eruption of volcanoes takes only a few seconds.deltas - The slow and steady flow of rivers form deltas and may take up to thousands of years.Earthquakes - It occurs within a few seconds after the fault ruptures and the ground shakes.Thus, the change that is not rapid is the formation of deltas.
https://brainly.com/question/20639139
is a archaebacteria cell wall present or absent
Answer:
Archaebacteria have cell wall made of complex composition of peptidoglycan
Please help i am giving brainliest
What is homeostasis?
A. the ability of an organism to maintain a relatively stable internal environment.
B. the production of a hormone by an endocrine gland that works on another endocrine gland
C. a series of events that monitor how hormones work in the body
D. a process in which a change in the environment causes a response that returns conditions
to their original status
No dam links
Answer:
A
Explanation:
Homeostasis is basically the organism being able to live without need of an outside source
Answer:
ok i answered the last one and yess i got it
What is homeostasis and how is it maintained?
Homeostasis refers to the body's ability to maintain a stable internal environment (regulating hormones, body temp., water balance, ect.). Maintaining homeostasis requires that the body continuously monitors its internal conditions.
Explanation:
hope it helps
Cold air usually pushes warm air because cold air has a _____________.
A. higher density
B. lower density
C. lower pressure
D. higher molecule speed
The sequence of mRNA is AGUACA. Which of these is the sequence of
tRNA? *
UCAUGU
AGTACA
AGUACA
TCATGT
Answer:
I think the answer is ucaugu
Three reasons why food self sufficiency Is
important ?
Answer:
FSS has become increasingly important to the political agenda in several countries, especially after the high volatility of food prices between 2007 and 2008 crisis [29-33]. Countries considered self-sufficient at the national level may have a percentage of their population with problems of hunger and malnutrition.
Explanation:
What is the ratio of the offsprings physical appearance
Answer:
1:2:1Explanation:
Hope this helps you :)
Which of the following sources of noise pollution has the greatest likelihood of leading to hearing loss
for exposed individuals in an urban area?
Your answer:
car horns
conversation
pneumatic drills
trains passing by
O traffic on a residential street
Answer:
traffic on a residential street
The relationship between the remora is and the shark is an example of
Answer:
An example of mutualism is the relationship between remora and shark.
Explanation:
Remora depends on sharks for food and locomotion. It has a sucking mouth that helps it to attach itself to the shark.
What are two things you would do to protect wetlands?
Answer:
Household Plants and Gardens. By practicing a little care in our gardens, we can help the wetlands immensely
Help Wetland Wildlife.
Explanation:
Those are two things, but there's more if you need any, just comment and I'll list them to you.
Which of the following is a function of the nucleus?
stores DNA
builds protein
stores sugars
packages proteins
Answer:
Stores DNA
Explanation:
Regulates activities in the cell and carries heredity information which is contained by genes and structures.
(06.04 LC)
Fertilization usually occurs in the (3 points)
A. End of the Fallopian tubes B. Vagina
C. Ovaries
D. Uterus
Answer:
A
Explanation:
ATP is chemical energy that all cells use.
O True
O False
Answer:
true
Explanation:
Adenosine triphosphate is broken into adenosine diphosphate, giving off energy in the process. This occurs during both cellular respiration and photosynthesis.
Answer:
TRue
Explanation:
ATP is the energy carrying molecule that is found in the cells of all living things
Population density is a measure of the number of individuals
per unit area.
A.True
B.False
When the cells start multiplying at an abnormal rate it leads to complications in our body.What could be the reason for this?Find Out
Answer:
the reason is often cancer.
Explanation:
cancer cells multiply rapidly and cause tumors
Normal red blood cells slide easily through narrow blood vessels. In sickle cell disease, many red blood cells change to a crescent shape like a slender moon. Crescent-shaped blood cells cause blockages in blood vessels. These blockages decrease the transport of oxygen. People with sickle cell disease often have sharp pains due to the lack of oxygen in parts of the body.
(Will mark Brainliest when someone answers)
The sickle cell version of the gene that causes sickle cell disease is recessive. Suppose that two parents with no symptoms have a child with sickle cell disease. What genes did the child inherit from the parents?
Answer:
C- the child must have inherited the gene from both parents.
Explanation:
Both parents could carry the trait and have no symptoms, but both parents passed it down to their child causing the child to have sickle cell anemia.
4
Select all the correct answers.
Which three human activities lead to a loss of terrestrial habitat?
conservation
farming
deforestation
construction
Reset
Next
Answer:
farming, deforestation, and construction
Explanation:
all of these options except conservation lead to poor environmental health. it's not conservation because to conserve means you are not wasteful and you conserve your resources.
Answer:
Farming, deforestation and construction all lead to the loss of terrestrial habitat. Conservation would be protecting terrestrial habitat.
Explanation:
Which part of a molecule provides energy for life processes? *
(1) carbon atoms
O (2) oxygen atoms
(3) chemical bonds
(4) inorganic nitrogen
Answer:
I believe the answer is #3, chemical bonds.
Answer:
I think option 3 chemical bonds is right answer
write the compliment triplets for the DNA sequence in each box in the following “ATG, ATC, GCA, AGT, AGC, GCC, GAT, AAG, TTG, CAG, TAG
Answer:
The complementary DNA sequence of each triplet is as follows:
ATG - TAC
ATC - TAG
GCA - CGT
AGT - TCA
AGC - TCG
GCC - CGG
GAT - CTA
AAG - TTC
TTG - AAC
CAG - GTC
TAG - ATC
Explanation:
A double-stranded DNA molecule is made up of two strands of DNA whose sequence are complementary to one another and linked by hydrogen bonds. According to the complementary base pairing rule as postulated by Chargaff, Adenine base will always hydrogen pair with Thymine base while Guanine base will always hydrogen pair with Cytosine base i.e. A-T, G-C
Based on the above explanation, the following triplets of DNA will have the following complementary sequences:
ATG - TAC
ATC - TAG
GCA - CGT
AGT - TCA
AGC - TCG
GCC - CGG
GAT - CTA
AAG - TTC
TTG - AAC
CAG - GTC
TAG - ATC
A student is studying the levels of organization in living things and creates a table to give examples of the different levels.
Which of these should the student write as an example of the organism level of organization?
human
stomach
connective tissue
food, water, and air
What do homologous and analogous
structures have in common?
1. Which of the following most accurately complete the statement below -
An increase in biodiversity result in
A. More competition for abiotic factors
B. Less competition for biotic factors
C. An increase in the sustainability of an ecosystem
D. A decrease in the sustainability of an ecosystem
Answer:
The correct answer is - C. An increase in the sustainability of an ecosystem.
Explanation:
Biodiversity is the variety of different biological species and populations on the earth or in an ecosystem. Biodiversity helps in maintaining health by providing food and other resources. Higher biodiversity healthier the earth.
Sustainability is the ability to maintain the ecological process and its structure and function in case of external stress for a longer time. The more sustainability of an ecosystem the healthier the ecosystem. The biodiversity of an ecosystem provides sustainability to the ecosystem. An increase in biodiversity will lead to a more sustainable ecosystem.
List developmental changes in animals
Mutations that change the structure or number of chromosomes are called
chromosomal mutations. ¿What is the difference between
inversion and translocation?
An inversion is pretty much when the chromosome breaks and rearranges itself, and translocation is when a part of a chromosome is transferred to another chromosome. hope it helped :)
A controlled experiment was conducted to analyze the effects of darkness and boiling on the photosynthetic rate of incubated chloroplast suspensions. The dye reduction technique was used. Each chloroplast suspension was mixed with DPIP, an electron acceptor that changes from blue to clear when it is reduced. Each sample was placed individually in a spectrophotometer and the percent transmittance was recorded. The three samples used were prepared as follows.
Sample 1 – chloroplast suspension + DPIP
Sample 2 – chloroplast suspension surrounded by foil wrap to provide a dark environment + DPIP
Sample 3 – chloroplast suspension that has been boiled + DPIP
On the axes provided, construct and label a graph showing the results for the three samples.
Answer:
where's your data? tho, i think we're answering the samee thingggg. here's mineee