_____ 1. The outer layer of the blastocyst that attaches to the wall of the uterus at implantation is called the
- a. amnion.
- b. yolk sac.
- c. cembryoblast.
- d. trophoblast.
Introduction:
Fertilization is defined as the process by which male and female gametes are the fuse to form a zygote and it is further developed into an embryo. The zygote form contains a diploid number of chromosomes.
Answer to Problem 1DYB
Correct answer:
Trophoblast is the outer layer of the blastocyst which is attached to the wall of the uterus at implantation. Therefore, option d. is correct.
Explanation of Solution
Reason for the correct statement:
Option d. is given as “trophoblast”. Trophoblast is an outer layer of cells that surrounds the fluid-filled cavity. These cells will form chorion. It plays an important role in implantation of the embryo and also in the formation of the placenta.
Hence, option d. is correct.
Reasons for the incorrect statements:
Option a. is given as “amnion”. It is an extraembryonic membrane formed from epiblast layer. It is a thin membrane. Hence, option a. is incorrect
Option b. is given as “yolk sac”. It is the first extraembryonic membrane and is formed from hypoblast layer. Hence, option b. is incorrect.
Option c. is given as “embryoblast”. It is the inner mass of the blastocyst. Hence, option c. is incorrect.
Hence, options a., b., and c. are incorrect.
Trophoblast is the outer layer of the blastocyst which is involved in embryo implantation.
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Chapter 29 Solutions
ANATOMY+PHYSIOLOGY:INTEGRATIVE APP (LL)
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- The trophoblasts of blastocyst will become the ____________. Question 12 options: a) chorionic sac & maternal portion of the placenta b) amniotic cavity c) inner cell mass d) chorionic sac & fetal portion of the placentaarrow_forwardChorionic villi develop from:- a. the zona pellucida. b. the endometrium. c. the syncytiotrophoblast. d. the embryoblast. e. the epiblastarrow_forwardThe surface that enables active and passive exchange between the fetal and maternal bloodstreams is the (a) yolk stalk. (b) chorionic villi. (c) umbilical veins. (d) umbilical arteries.arrow_forward
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