Question

22. The inner call mass of a blastocyst is comprised of cells that are A) multipotent B) pluripotent c) fotipotent. D) None of the above 23. What is the most difficult part of creating a human heart from stem cells? A) inducing the stem cells to become beating cardiac cells B) isolating the stem cells C) creating the "scaffold of the heart and structures like valves that are not made of cells 24. Which of the following structures on the ovum (egg) contains special receptors for binding to the sperm A) zona pellucida B) corona radiata C) nucleus D) acrosome E) mitochondria 25. After fertilization, a hollow ball of cells called a forms, followed by Implantation into the ute wall and the process of cell differentiation, also known as A) blastocyst: gastrulation B) zygote, monulation c) blastocyst: morulation D) gastrula; morulation E) Morula, blastulation 26. Which of the following is NOT a role of the placenta during pregnancy? A) exchange of blood cells between baby and mom B) exchange of oxygen and carbon dioxide between baby and mom C) exchange of nutrients and waste products between baby and mom D) production of hormones such as progesterone that maintain the pregnancy 27. A hormone produced in early pregnancy that can be detected on a home pregnancy test is called: A) human chorionic gonadotropin B) progesterone C) estrogen D) Oxytocin E) FSH 28. The human brain completes the development process at age: A) at birth (the brain is one of the first organs to complete development). B) at 9 months, once the baby can no longer distinguish sounds that it hasn't heard C) at 5 years, which is why we start formal schooling at this age D) at 18 years, which is the legal age of adulthood E) at age 25, because the human brain develops and matures very slowly! Genetics & Biotechnology 29. How many alleles do you inherit for each gene? A) 1 B) 2 C) 4 D) it varies for different genes

Answer 1

22. Inner cell mass differentiates into ecto,meso and endoderm .

These germinal layers later on make the whole body .

Each cell of inner cell mass have capicity to give rise the germinal layers ,hence ,IT IS TOTIPOTENT.

23.valvs are not made of cells ,hence it is difficult to make it from stem cell.

24.zona pellucida is the noncellular layer below the corona radiata.it contains receptors for attachment of sperm.

25.BLASTULA-hollow ball like structure .

GASTRULATION-the process of differentiation of blastula into three germinal layer,ectoderm,mesoderm and endoderm.

26,exchange of blood cell from baby to mom is not possible because it will lead to graft rejection.

27.hCG is produced in early pregnancy (trimaster), is used to detect pregnency through urine.

28. Age of 25 year is supposed to be comlete development of brain because the cortex area is not further developed.

29. Two set of information is present in our cell in the form of diploid stage ,hence there are two allels present for each gene.