Answer
At week 5-6 of gestation, the baby’s heart starts beating.
Explanation
Fertilization occurs in week 3 followed by implantation in week 4.In week 5 the levels of hormones increases with formation of the baby’s heart and circulation system. In week 6, the neutral tube closes followed by development of structures necessary to form eyes and ears. The head of the baby develops at week 7 followed by nose in week 8 and toes in week 9.
Answer:
Peripheral vascular resistance (systemic vascular resistance, SVR) is the resistance in the circulatory system that is used to create blood pressure, the flow of blood and is also a component of cardiac function. When blood vessels constrict (vasoconstriction) this leads to an increase in SVR.
The relationship between BP and viscosity is such that, given a constant systolic BP, if blood viscosity increases, then the total peripheral resistance (TPR) will necessarily increase, thereby reducing blood flow. Conversely, when viscosity decreases, blood flow and perfusion will increase.
Answer:
science is different from many other ways of learning because of the way it is done. Science relies on testing ideas with evidence gathered from the natural world.
Hope this helps
<h2><u>
Answer:</u></h2>
<u>Organic molecules:</u> are biologically important ones.All macro molecules are made up of simple molecules (monomers) that are bounded by specific bonds .Biologicaly important molecules are proteins ,fats ,carbohydrstes and nuclic acid.All these molecules are formed by condensation of monomers.
<u>proteins:</u> Proteins are made up polymers of amino acids. Aminoacids ae joined together by peptide bond.
A peptide bond is a chemical bond formed between two amino acid molecules when the carboxyl group of one molecule reacts with the amino group of the other molecule and releasing a molecule of water (H2O).
<u>Carbohydrates: </u> are biological important one are made up of monosaccharides and the are joined together by glycosidic bond.
<u>Fats:</u> are made up of fatty acids are joined together by covalent bonds called ester bond . Saturated fatty acids are bound by single anu unsaturated are made up of double or triple bonds.
<u>Nucleic acid:</u> are made up of nucleotides .Nucleotides are joined together by chemical bond called hydrogen bond.It is formed between the phosphate group of one nucleotide and the sugar of a neighboring nucleotide holds the backbone together.
They have a double- bonded oxygen in different locations.