6.3 Sexual Reproduction, Pregnancy, and Fetal Development Part 3

Question 1

What is the first trimester?

Answer 1

1-3 months

Question 2

What is the second trimester?

Answer 2

4-6 months

Question 3

What is the third trimester?

Answer 3

7-9 months

Question 4

When does the heart begin to beat?

Answer 4

3 weeks

Question 5

When are the cardiovascular and nervous systems forming?

Answer 5

first trimester

Question 6

When can the fetal heartbeat be detected on ultrasound?

Answer 6

week 6

Question 7

When does neuralation occur?

Answer 7

week 5

Question 8

What is neurulation?

Answer 8

formation of the neural tube from the outer folds of the ectoderm

Question 9

What is the first step of neurulation?

Answer 9

lateral sides of the ectoderm converge together to form the epidermis superficially

Question 10

What is the second step of neurulation?

Answer 10

neural folds form underneath the epidermis forming the neural crest

Question 11

What occurs during the third step of neurulation?

Answer 11

neural plate becomes the neural groove which becomes the neural tube

Question 12

What does the anterior portion of the neural tube become?

Answer 12

brain

Question 13

What is spina bifida?

Answer 13

when neuralation does not completely close the neural tube

Question 14

What are symptoms of spina bifida?

Answer 14

varying levels of sensory/motor disabilities

Question 15

What can pregnant mothers take in order to help prevent neural tube defects?

Answer 15

folic acid

Question 16

When is the embryo considerd a fetus?

Answer 16

week 8

Question 17

When do arms and legs begin to form?

Answer 17

first trimester

Question 18

What is the fetus able to do by week 13?

Answer 18

moveable joints, fingers, and toes

Question 19

What happens during the second trimester to the fetus?

Answer 19

eyes, ears, and nose move to the correct position on the face
head and body grow to proper proportions

Question 20

What occurs around the 16th week to the fetus?

Answer 20

eyes are developed enough to detect light and dark