10.4 Introduction to Embryology

Question 1

is a study of the development of the fertilized ovum from the fertilization to birth

Answer 1

Embryology

Question 2

is the term used to define the developing fertilized ovum to the end of the second month of the intrauterine

Answer 2

Embryo

Question 3

in the human refers to the developing fertilized ovum from the beginning of the thirds month of intrauterine life until birth

Answer 3

Fetus

Question 4

has been define as the expulsion of an ovum from a vesicular (Graafin) follicle and ovary into the pelvic cavity

Answer 4

Ovulation

Question 5

is the union of an ovum and spermatozoon, resulting in a cell with 46 chromosome, or 23 pairs, including 23 chromosomes from the ovum and 23 from the spermatozoon

Answer 5

Fertilization

Question 6

is the female or male mature reproductive cell, an ovum or spermatozoon

Answer 6

Gamete

Question 7

is the cell produced by the union of an ovum (female gamete) and a spermatozoon (male gamete).A fertilized ovum

Answer 7

Zygote

Question 8

includes the time the embryo and fetus spend within the uterus

Answer 8

Intrauterine or neonatal period

Question 9

the fertilized ovum divides and redivides repeatedly by mitotic cell division

Answer 9

Segmentation or cleavage

Question 10

the center of the ball becomes hollowed out and fills with fluid

Answer 10

Hollow ball of cells

Question 11

is a sac filled with fluid that surrounds the developing embryo and fetus, and in which the embryo floats

Answer 11

Amniotic Cavity

Question 12

outer layer, by a process of repeated cell division forms a covering membrane that surrounds the outer layers, to become the outer layer of skin

Answer 12

Ectoderm

Question 13

following a period of development including the formation of a yolk sac, forms a tube from the head end to the lower end of the embryo

Answer 13

Endoderm or inner layer

Question 14

the middle layer develops between the outer layers, and separates into several parts

Answer 14

Mesoderm

Question 15

Structures Formed from the 3 Basic Layers: The ectoderm

Answer 15

• Skin, hair, nails
• The central nervous system, brain and cord
• Enamel of the teeth
• Lining of mouth, nasal cavities. etc

Question 16

Structures Formed from the 3 Basic Layers: The mesoderm

Answer 16

• Skeletal and visceral muscle
• Connective tissue and derivatives; fat cartilage, bone, fibrous and elastic tissues
• Blood vessels and the heart
• Part of the urinary system

Question 17

Structures Formed from the 3 Basic Layers: The entoderm

Answer 17

• lining membranes of digestive tract
• Trachea and lungs
• Liver, pancreas, gall bladder, bile ducts
• Urinary bladder, etc

Question 18

X + X

Answer 18

female embryo

Question 19

X + Y

Answer 19

male embryo

Question 20

form if 2 ova mature at the same time and are both fertilized

Answer 20

Fraternal twins

Question 21

form if a single ovum is fertilized by a single spermatozoon, and is during segmentation the ball of cells divides into two identical parts

Answer 21

Identical twins

Question 22

occur when the separation of an ovum is incomplete

Answer 22

Siamese twins

Question 23

form by a division of an ovum into three identical embryos

Answer 23

Triplets