Answer:
a. sexual dimorphism was developing over time in these species
Explanation:
Sexual dimorphism is an evolutionary change that occurs over time in species, which could be as a result of sexual selection which makes both sex of a species develop a systematic difference in form, which can manifest in terms of body size, color, secondary sex characteristics, and size of some structures such as larynx size which accounts for deeper voices in males in relation to levels of testosterone. This is later passed across from generation to generation over time.
In general, each species of fruit fly in the Hawaiian archipelago is restricted to a single island. One hypothesis to explain this pattern is that new species formed after a small number of flies colonized each new island. This mechanism is called:
Answer:
Geographical isolation
Explanation:
The formation of new species by a small number of fruit flies colonized each new island. This mechanism is called geographical speciation or allopatric speciation.
The geographical speciation takes place when some members (biological populations) of the same species become isolated due to geographical changes such as mountain building or migration. Due to isolation, the organisms prevents two or more groups from mating with each other on regular basis. The gene flow between them is greatly reduced which eventually causing that formation of new species.
The Minnesota Department of Natural Resources has introduced regulations that require the use of approved firewood in state parks, state forests and wildlife management areas. There is specific approved firewood for each area which can't be used in other protected areas. What is the most likely reason for these restrictions? A) To clear excess wood from trees that have fallen or been removed in the parks. B) To avoid the introduction or spread of insects or disease that damage native trees. C) To generate revenue for the department by restricting the sale of firewood by outside vendors. D) To eliminate the use of highly flammable firewood that might lead to uncontrolled forest fires.
Answer:
The correct answer is option B) "To avoid the introduction or spread of insects or disease that damage native trees".
Explanation:
The regulations introduced by the Minnesota Department of Natural Resources include the proper handling of firewood, which prohibits the use of firewood from one protected area into other protected areas. The reason behind this regulation is to avoid the introduction or spread of insects or disease that damage native trees. Each tree in each protected location is adapted to its local fauna. Serious environmental damage could arise from introducing insects from a protected area to another by improper handling of firewood.
Insulin is a protein that is produced by pancreatic cells and secreted into the bloodstream. Which of the following options correctly lists the order of the structures through which insulin passes from its production to its exit from the cell?
The question can be answered on the basis of general transport of proteins.
Answer:
The endomembrane system is present in the eukaryotes that includes the cell organelle that divides them into the structural and functional unit of the cell. This helps in the protein sorting and its transport.
The insulin is the hormone that made of the alpha and beta peptide through the disulfide linkage. The protein must enter in the rough endo plasmic reticulum for the signal recognition and modification of protein. Then the protein moves into the golgi through the vesicles and finally into the endocytosis through the cell membrane.
sulcus The extra bones that sometimes develop between the flat bones of the skull are called bones. Small bones occurring in some tendons in the hand or foot are called bones. The cranium and facial bones compose the . The bone supports the tongue. The at the inferior end of the sacrum is composed of several fused vertebrae. Most ribs are attached anteriorly to the .
Explanation:
Sutures are a type of fibrous joint that binds two bones together into a solid, immobile expanse of bone. We are most familiar with sutures in the skull that connect the different cranial bones Sesamoid bones are small bones embedded in tendons where they pass over a joint. The most prominent sesamoid bone is the kneecap, officially known as the patella. tSurrounding your brain is the part of your skeleton known as your skull. Your skull is made of bone and cartilage, or firm tissue; its job is to protect your brain. Some of the bones surrounding the brain, and some of the bones are facial bones. Facial bones are bones like the jaw and cheekbonesThe hyoid bone is small, U-shaped bone in the throat. It is located in the front, middle of the throat between the lower jaw and the larynx, which is also called the voice box. The hyoid bone is involved in several functions of the throat, including breathing, swallowing, and talkingThe coccyx is a small bone at the base of your spine.Our spines are made up of 24 small bones in our back that support the weight of our bodyThe sternum is one of the largest flat bones in the human body. It located in the center of the chest, which is why it is often called the breastboneSutural bones develop between the flat bones of the skull. Sesamoid bones occur in tendons and protect them. The skull consists of cranial and facial bones.
Explanation:The bones that sometimes develop between the flat bones of the skull are called sutural bones. These bones form irregularly shaped bones that fill the gaps in the cranium's flat bones.
Small bones occurring in some tendons in the hand or foot are called sesamoid bones. They function to protect tendons from excessive wear and tear and aid in tendon function.
The cranium and facial bones together compose the skull. The skull consists of cranial bones and facial bones that support the structures of the face and protect the brain.
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If a horticulturist breeding gardenias succeeds in having a single plant with a particularly desirable set of traits, which of the following would be her most probable and efficient route to establishing a line of such plants?A) Backtrack through her previous experiments to obtain another plant with the same traits.B) Breed this plant with another plant with much weaker traitsC) Clone the plant.D) Force the plant to self-pollinate to obtain an identical one
Explanation:
To clone a plant means to create an identical copy of an adult plant. These identical copies become young plants that in turn become adult plants that can be cloned again. This process can go on indefinitelyThe most common method of cloning plants and the one that has been used for a very long time is that of taking cuttings from an adult plant. A cutting is a stem or leaf that is cut from an adult plant. The cutting is then planted into moist soil or other moist growing media. The cutting will produce roots of its own and then become a whole new plant identical to the original adult plant. Not all plants can be cloned via cuttings, thoughVegetative proliferation works in light of the fact that the finish of the cutting structures a mass of non-particular cells called a callus. With karma, the callus will develop, gap and structure different specific cells (roots, and so on.), in the end framing another plantHence, the right answer is option C "Clone the plant"
Which groups in the domain archaea require high salt concentrations for survival?
Answer:halophiles
Explanation:archaea and bacteria are the types groups of prokaryotes.prokaryotes are organism which lacks membrane bound organelle including the nucleus.as a result,they contain their chromosomes in the nucleoid;a poorly defined region in the cytoplasm.
Archaea and bacteria have several differences including in their cell wall.the cell wall of archaea contains isoprene while that of bacteria contains fatty acid chains.
Archaea are found in extreme environment. The methanogens are obligated anaerobes that produces methane gases and lives in swamps and sewage treatment plants.
The halophiles only lives in water with high salt concentration .
Some lives in acidic and sulphur hot springs and also in ocean depths
The apoplast in plant tissues consists of:________. a. cell walls, extracellular spaces, and vessel elements b. cell walls, extracellular spaces, and plasmodesmata c. vessel elements, plasmodesmata, and extracellular spaces d. cell walls, plasma membrane, and cytosol
The correct answer is a. cell walls, extracellular spaces, and vessel elements.
Here's why the other options are incorrect:
* b. cell walls, extracellular spaces, and plasmodesmata: Plasmodesmata are specialized channels connecting the cytoplasm of adjacent cells, and they are considered part of the symplast, not the apoplast.
* c. vessel elements, plasmodesmata, and extracellular spaces: As mentioned above, plasmodesmata are part of the symplast. Additionally, vascular elements like xylem and phloem contain internal lumens, which are considered part of the apoplast, but not vessel elements themselves.
* d. cell walls, plasma membrane, and cytosol: The plasma membrane and cytosol are inside the plant cell, while the apoplast refers to the extracellular space outside the plasma membrane.
Therefore, the apoplast encompasses the non-living spaces outside the cell walls, including the cell walls themselves, the intercellular spaces between cells, and the internal lumens of xylem and phloem elements.
Bobby touches his newborn brother's palm, and his little brother takes hold of Bobby's finger and will not let go. This is known as the __________ reflex.
Answer: conditioned
Bobby touches his newborn brother's palm, and his little brother takes hold of Bobby's finger and will not let go. This is known as the conditioned reflex.
Explanation:
A conditioned reflex is a response or behaviour learned after birth. So, once the newborn acquires this learned response, they can perform them even without thinking about it.
Thus, Bobby's brother (the newborn) holding on to his finger and not letting go shows that it is a conditioned reflex
What is hypoxia why is it dangerous to the nervous system
Answer:
hypoxia is the absence of enough oxygen in the tissues to sustain bodily functions
Explanation:
The brain could cease to function and if it continues death or permament brain damage starts in few minutes
"Jasmine is trying to lose weight. She has decided to try a diet that lets her eat unlimited amounts of protein. The protein that Jasmine eats that is above and beyond what she needs is _____."
Answer:
converted into fat and stored in adipose tissue
Explanation:
When protein is taken in excess amount, because it cannot be stored in the body, it can be broken down to amino acids, which is further used as carbon skeletons to synthesize fats, which is then further stored in the adipose tissues.
When the body is not receiving enough calories from other nutrient sources like carbohydrates and fats, the available protein is the used as energy to meet the body's energy demands, by converting it to fat.
Note that, excess intake of protein can be harmful to the body.
____________ is a process that can completely catabolize an organic energy source to CO2 using the glycolytic pathways and TCA cycle with O2 as the terminal electron acceptor for an electron transport chain.1. Aerobic respiration2. Anaerobic respiration 3. Catabolism4. Anabolism
Explanation:
Aerobic respiration utilizes Oxygen.Aerobic breath happens in most cells.The measure of energy discharged is high which is around 36-38 ATP atoms. The stages engaged with aerobic respiration are glycolysis, krebs cycle, electron transport chain.The items which are formed in aerobic respiration are Carbon dioxide, Water and ATP.The reaction's site of aerobic respiration are Mitochondria and Cytoplasm. The reactants included are glucose and oxygen.The ignition is complete.The process which complete catabolizes an organic energy source to CO2 using glycolytic pathways and TCA cycle with O2 as the terminal electron acceptor is Aerobic respiration, a process that uses oxygen to breakdown glucose into water and carbon dioxide, releasing ATP in the process.
Explanation:The process described that can completely catabolize an organic energy source to CO2 using the glycolytic pathways and TCA cycle with O2 as the terminal electron acceptor for an electron transport chain is called Aerobic respiration.
Aerobic respiration is the process by which organisms like animals and plants break down glucose into water and carbon dioxide in the presence of oxygen, releasing high-energy molecules (ATP) as a result. The process happens in three major steps: glycolysis, the Krebs cycle (or TCA cycle), and the electron transport chain. Oxygen acts as the terminal electron acceptor in the electron transport chain, resulting in the formation of water molecules.
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Two birds who are identical twins (i.e., have exactly the same genotype), are raised in different zoos. One of them has a red crest as an adult and the other has a yellow crest. What is the most likely conclusion you can draw regarding the heritability of crest color?
Answer: The crest color was determined by the environment
Explanation:
Identical twin birds having the same genotype shows that the genetic material is same in the cells of both. However, the difference in crest color is based on each bird adaptation to its environment
Thus, environment, just as genotype imparts the traits of an organism.
Phylogenetic trees constructed from evidence from molecular systematics are based on similarities in _____.
Answer:
mutations to homologous genetic loci
Explanation:
Phylogenetic tree, which is a diagrammatic representation of evolutionary relationship among organisms, can be constructed from evidence from molecular systematic with regard to the similarities in the mutations to homologous genes.
Homologous genes are genes that are inherited by two species from a common ancestor having similar DNA sequence. An example of homologous gene is Orthologous gene, which is said to have be brought about by speciation.
In a laboratory experiment, one group of people consumes an amount of pure water, a second group an equal amount of beer, and a third group an equal amount of concentrated salt solution that is hypertonic to their blood. Their urine production is monitored for several hours. At the end of the measurement period, which group will have produced the greatest volume of urine and which group the least?
Answer:
Salt solution
Explanation:
The body releases salt and water that the body doesn't need .. therefore the body would get rid of the salt solution the most from the added salt
Global warming has been hypothesized to cause many plants to flower earlier. If bees search for food earlier in response to this, this would represent ________ within the community.
Coevolution
Explanation:
Coevolution is the phenomena in which two interacting species evolve under the influence of each other.
Global warming caused a drastic rise in temperature. The temperature condition during the original flowering season became higher than the optimum flowering temperature. So, the flowering plants began to flower earlier.
This created a food crisis for bees who were adapted to collect food during the flowering season. However, they evolved along with the flowering plants and started searching food earlier.
So we can say that evolution of flowering plant caused the evolution of bees.So it is a coevolution.
Dorothy Peterson was diagnosed with breast cancer. She and her doctor agreed upon treating this surgically with a/an . This is a procedure in which the cancerous tissue with a margin of normal tissue is removed.
Answer: Lumpectomy
Explanation: Lumpectomy is procedure in which Cancerous tissues are removed. Lumpectomy is a surgical removal of lump or cancerous tissue of breast tissue usually in the treatment of breast Cancer.
Which structure is correctly paired with its tissue system?
companion cell – ground tissue
root hair – vascular tissue
guard cell – vascular tissue
tracheid – vascular tissue
The study of plants is called botany.
The correct answer is option D which is tracheid-vascular tissue.
What is a tissue system?All the tissue is made up of cells and when more than one tissue worker together to perform a single function is called a tissue system.What is vascular tissue?The tissue which is made up of vessels is called vascular tissue. For example - xylem and phloem.The tracheids are part of the xylem hence, it is related to the vascular tissue.
Hence, the correct option is D.
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In order to distinguish the DNA of one person from another, scientists often rely on the presence of short tandem repeats (STRs). These consist of short DNA sequences that are repeated many times in a row. Why are STRs useful for identification
Answer:
STR can be defined as the short tandem repeats which is generally different in people.
It is unique to the person and have a very slow rate of mutation and because of this property these fragments are stable and predictable.
They have a higher power of discrimination and is highly used in the identification of the human beings. It is used on a regular basis in case of forensic science, for the identification of victims, missing person and other criminal cases.
As her professor distributed the mathematics test to the class, Blair's heart started to pound and her palms began to sweat. These physiological reactions were activated by her ________ nervous system. Group of answer choices central endocrine sympathetic somatic parasympathetic
Answer:
sympathetic nervous system
Explanation:
The sympathetic nervous system is part of the autonomous nervous system which controls the involuntary body functions as heart rate, breath rate, perspiration etc. The sympathetic nervous system is specifically responsible for the increase in the function of body functions when the body perceives a threat. When faced with a threat or distress, the sympathetic nervous system initiates physiological reactions known as the “fight or flight” response, thereby increasing the body’s alertness to such threat. Examples of increased body functions or “fight or flight response” include increased perspiration and increased heart rate, as exhibited by Blair.
The answer is the Sympathetic nervous system as a Group of answer choices central endocrine sympathetic somatic parasympathetic shows these symptoms.
The sympathetic nervous system is a part of the self-sustaining fearful device which controls the involuntary frame capabilities such as coronary heart rate, breath rate, perspiration, etc. The sympathetic is in particular answerable for the boom withinside the feature of frame capabilities while the frame perceives a risk. When confronted with a risk or distress, the sympathetic nervous system initiates physiological reactions called the “combat or flight” response, thereby growing the frame’s alertness to such risk. Examples of improved frame capabilities or “combat or flight response” consist of improved perspiration and improved coronary heart rate, as exhibited via way of means of Blair.
What is the sympathetic nervous system?The sympathetic nervous system directs the body's speedy involuntary reaction to risky or disturbing situations. A flash flood of hormones boosts the body's alertness and system coronary heart rate, sending greater blood to the muscles.
Hence conclude the sympathetic nervous system is the answer.
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Neutrophils engulf microbes by phagocytosis to fight an infection. Normally, they perform this function for some time but then die off. These dead cells and other foreign materials form pus. What cells then clean up all the dead neutrophils?
Answer:
Macrophages engulf the dead neutrophils and the process is known as Phagocytosis.
Explanation:
Neutrophills are white blood cell that are produced by bone marrow which is released into the blood stream and they have short life span as they die in 1 day.These neutrophills along with other WBC are engulfed by macrophages which are also freely moving on the blood stream.
These mature macrophage plays a crucial role as it locates the foreign body and eat them.
They use the process of phagocytosis and engulf the unwanted particles.
When the macrophages engulf the particle,phagosome is formed which is a pocket like structure then lysosome release enzymes that digest the particles.
Resistance in the blood vessels is primarily controlled by altering
All of the following are true of natural selection, EXCEPT A. it results in a change in allele frequencies over time. B. it works best in genetically uniform populations. C. it is the process by which evolution occurs. D. it results in some individuals surviving better and reproducing more than others. E. it results in populations better suited to their environment than their predecessors.
Answer:
B. it works best in genetically uniform populations.
Explanation:
Natural selection: The environment will determine which traits are used as and advantage to breed more successfully.
If every being of that specific species was exactly the same then natural selection would kill them all off at once.
If you had a zebra that was white and one that had stripes. the one with stripes would last longer.
It works best in genetically uniform populations is not true except natural selection.
What is natural selection?
An evolutionary mechanism is natural selection. Environment-adapted organisms have a higher chance of surviving and dispersing the genes that contributed to their success. Over time, this mechanism leads to the evolution and divergence of species.
One way to explain the millions of species that have existed on Earth is through natural selection.
Natural selection results in the transmission of advantageous genetic variants through reproduction. As a result, a new generation of organisms emerges that has a higher chance of surviving and reproducing.
For instance, giraffes have an edge over other species due to their long necks, which have allowed them to graze on leaves that others cannot reach. Those with longer necks were able to grow larger because of a greater food source.
Therefore, It works best in genetically uniform populations is not true except natural selection.
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Hemoglobin is the protein that transports oxygen in mammals. Hemoglobin is 0.347% by mass, and each hemoglobin molecule contains four iron atoms. Calculate the molar mass of hemoglobin.
Answer:
Molar mass of hemoglobin is 64380.4 g/mol
Explanation:
Percentage of Fe calculated from the equation
%Fe = 4×molar mass of Fe/molar mass of hemoglobin.(4 because hemoglobin contain 4 Fe atoms)
Molar mass of hemoglobin is =4×molar mass of Fe / % Fe
=4×55.85/.00347
=64380.4 g/mol.
The molar mass of hemoglobin is 64380.4 g/mol.
Calculation of the molar mass:Since Hemoglobin is 0.347% by mass,
here we have to determine the percentage of Fe
%Fe = 4×molar mass of Fe/molar mass of hemoglobin
So,
The molar mass of hemoglobin is
=4×molar mass of Fe / % Fe
=4×55.85/.00347
=64380.4 g/mol.
hence, The molar mass of hemoglobin is 64380.4 g/mol.
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What is true regarding rem sleep in infants?
The information is not available regrading the question and its option. The answer will consider the general points regarding the REM sleep in infants.
Answer:
Rapid eye movement (REM) sleep is the sleep that involves the rapid and random movement of the eyes. The muscle tone gets low during the REM sleep. This sleep is present in both infants and adults.
The baby start shows his legs and hands during the REM sleep. Most of the infants experience the REM sleep. The sleep become less active and the individual is more conscious during the REM sleep. The breathing of the infant is quite irregular in REM sleep.
All of the following are problems that growth causes for cells EXCEPT Select one: a. DNA overload. b. excess oxygen. c. obtaining enough food. d. expelling wastes.
Answer: Excess oxygen
Explanation:
The cell if gets food in optimum amount can grow and cause various problems and there are many problems associated with the growth of the cell.
They require more food and obtain enough of it. The bigger cell expels waste materials out of the cell.
The requirement of excess of oxygen is not a problem which is caused due to the excess growth of cell.
Maturation is defined as the __________.a. physical growth and development of the body, brain, and nervous system. b. organism's ability to adapt to changing condtions. c. sum of all the external conditions affecting development. d. transmission of physical and psychological characteristics from parent to offspring.
Final answer:
Maturation is the physical growth and development of the body, brain, and nervous system, marking key stages such as puberty where individuals become capable of reproduction. It's a component of lifespan development, which studies the changes from conception to death, and is influenced by both genetic and environmental factors.
Explanation:
Maturation is defined as the physical growth and development of the body, brain, and nervous system. This process encompasses the changes and growth that a person goes through, often highlighted during puberty when sexual organs mature and individuals become capable of reproduction. Maturation is an intrinsic development sequence guided by genetic factors but can be influenced by environmental factors as well. It is crucial in the context of lifespan development, which studies how individuals grow and change from conception to death. The nature versus nurture controversy further explores how both genetic predispositions (nature) and environmental influences (nurture) guide this growth and development, affecting traits such as personality, intelligence, and physical characteristics in complex ways. Understanding maturation and its role in human development provides insights into the comprehensive process of becoming mature, encompassing physical, cognitive, and psychosocial growth.
Too much calcium in the bloodstream, a condition called hypercalcemia, can be very dangerous. The thyroid gland releases a hormone, calcitonin, when calcium is too high. How does calcitonin lower calcium levels in the blood
Answer:
Calcitonin reduces blood calcium
Explanation:
Calcitonin reduces blood calcium by suppressing the activities of osteclast (bone cells that breaks down bone tissue resulting in excess calcium) and increase the amount of calcium passed out as urine.
Viruses can vary with respect to all of the following characteristics except _____. the type of host cell it can infect DNA or RNA as the genetic material single- or double-stranded nucleic acids the presence or absence of a membranous envelope the presence or absence of metabolic machinery
Answer:
the presence or absence of metabolic machinery
Explanation:
Here is the correct question:.
Viruses can vary with respect to all of the following characteristics except _____.
a) DNA or RNA as the genetic material
b) the presence or absence of metabolic machinery
c) single- or double-stranded nucleic acids
d) the presence or absence of a membranous envelope
e) the type of host cell it can infect
the presence or absence of metabolic machinery
Sickle-cell anemia is associated with a mutation in the gene encoding the beta subunit of hemoglobin that results in a change from glutamic acid to valine at position 6. All other amino acids are identical to a normal hemoglobin molecule. Based on the information above, which of the following mutations is the most likely cause of sickle-cell anemia?
a. A single base-pair substitution in the gene encoding the beta subunit.b. A single base-pair insertion in the gene encoding the beta subunitc. A single base-pair deletion in the gene encoding the beta subunit
d. A translocation of DNA from one chromosome to another
Answer:
AExplanation:
1. Sickle cell anemia is an inherited condition, disorder (disease).
2. It is a recessive condition, in which red blood cell become mutated and converted to a sickle like shape, and there aren't enough healthy red blood cells to carry oxygen throughout the body.
3. This condition normally occur when, there is inheritance of two abnormal or mutated copies of the β-globin gene, one allele from each parent.
4. β-globin gene makes haemoglobin.
5. Sickle cell anemia results when glutamic acid being substituted by valine at position 6 ( in short E6V substitution).
6. So, it a single base-pair substitution in the gene encoding the beta subunit.
"The correct option is a. A single base-pair substitution in the gene encoding the beta subunit. The most likely cause of sickle-cell anemia is a single base-pair substitution in the gene encoding the beta subunit of hemoglobin.
Sickle-cell anemia is caused by a mutation in the gene that encodes the beta subunit of hemoglobin. The mutation results in the substitution of a single amino acid, glutamic acid, with valine at position 6 in the beta-globin chain. Since glutamic acid is encoded by the codons GAA or GAG, and valine is encoded by the codons GTT, GTC, GTA, or GTG, a single base-pair change can result in this amino acid substitution.
For example, if the original codon for glutamic acid is GAG, a single base-pair substitution of A for T would change it to GTG, which codes for valine. This is a classic example of a point mutation, specifically a missense mutation, where a single nucleotide change in the DNA sequence leads to the substitution of one amino acid for another in the protein sequence.
The other options are less likely to be the cause of sickle-cell anemia:
b. A single base-pair insertion in the gene encoding the beta subunit: An insertion would shift the reading frame of the gene, leading to a completely different amino acid sequence downstream of the insertion, which is not the case in sickle-cell anemia.
c. A single base-pair deletion in the gene encoding the beta subunit: A deletion would also shift the reading frame, resulting in a nonfunctional protein or a protein with a different sequence than the one associated with sickle-cell anemia.
d. A translocation of DNA from one chromosome to another: Translocation involves the movement of large segments of DNA between chromosomes, which is not consistent with the single amino acid change observed in sickle-cell anemia.
Therefore, the most likely cause of sickle-cell anemia is a single base-pair substitution in the gene encoding the beta subunit of hemoglobin."
The foramen ovale..... A is a condition in which the heart valves do not completely close B is a shallow depression in the interventricular septum C connected the two atria in the fetal heart D is a connection between the pulmonary trunk and the aorta in the fetus
Answer:C. connects the two atria in the fetal heart
Explanation: The foremen ovale makes it possible for blood to go from the vein to the right side of fetus heart,and then to the left side of the heart. Before a baby is born,the baby gets blood rich in oxygen from the mothers placenta,and its delivered through the umbilical cord, because the baby can not use its lungs to get blood.