Tag: zoology

Questions Related to zoology

What is placenta? 

zoology reproduction in humans placenta pregnancy and birth fertilization and post fertilization in humans

  1. Special tissue connection between embryo and uterine wall

  2. Facilitate passage of nutrition and oxygen to embryo from mother through blood

  3. Waste substances produced by embryo are removed through placenta into mothers blood

  4. All of the above

Show answer
Correct Option: D
Explanation:

  • Placenta is a special organ or tissue that connects the developing fetus to the uterine wall. It allows nutrient uptake, waste elimination, gas exchange via the mother's blood supply, fight against internal infection and produces a hormone to support pregnancy.

Therefore, the correct answer is option D.

What is formed by chorionic villi cooperating with the tissues of uterus of mother?

zoology reproduction in humans placenta pregnancy and birth fertilization and post fertilization in humans

  1. Placenta

  2. Embryonic disc

  3. Umbilical cord

  4. Embryonic layer

Show answer
Correct Option: A
Explanation:
The chorion, which means as the membrane covering the fetus is the outermost extraembryonic membrane. The two types of cells namely cytotrophoblast cells and syncytiotrophoblast cells form chorion. These cells combine with the functional layer of the endometrium and form the placenta, which is the site of gas and nutrient exchange between the embryo and the mother. Hence, the correct answer is option A, Placenta.

The most primitive type of mammalian placenta is

zoology reproduction in humans placenta pregnancy and birth fertilization and post fertilization in humans

  1. Syndesmochorial

  2. Endotheliochorial

  3. Haemochorial

  4. Epithelicohorial

Show answer
Correct Option: D
Explanation:
Epitheliocohorial type of mammalian placenta is observed in cattle, pigs etc
wherein the chorion is superficially aligned on the endometrium and does not penetrate it.
So, the correct answer is 'Epithelicohorial'

Haemoendothelial placenta occurs in

zoology reproduction in humans placenta pregnancy and birth fertilization and post fertilization in humans

  1. Man and Ape

  2. Cow and Goat

  3. Deer and Camel

  4. Rat and Rabbit

Show answer
Correct Option: D
Explanation:

In the hematoendothelial placenta, the outer covering which is the trophoblast becomes so thin that it appears that the maternal blood is separated from the fetal blood only by a single layer of cells of the embryonic layer chorion. This type of placenta is generally found in Rat and rabbit.


So, the correct option is ' Rat and Rabbit.'

Considering the following:
1) Endothellium of foetal blood capillaries 
2) Connective tissues surrounding foetal blood capillaries
3) Chorionic epithelium
4) Maternal epithelium 
5) Connective tissue surrounding maternal blood capillaries 
6) Endothelium of maternal blood capilaries 
In the case of humans, the placenta comprises which of the above?

zoology reproduction in humans placenta pregnancy and birth fertilization and post fertilization in humans

  1. 1 , 2, 3, 4, 5 and 6

  2. 1, 2, 3 and 6

  3. 1, 2 and 3

  4. 1, 2, 3 and 5

Show answer
Correct Option: A
Explanation:

The human placenta has chorionic epithelial cells. It has maternal endothelial cells of blood capillaries, maternal endometrial epithelium and endothelium of foetal blood capillaries. The foetal connective tissue surrounds the foetal endothelial blood capillaries. The maternal connective tissue surrounds the maternal blood capillaries. 

Thus, the correct answer is '1, 2, 3, 4, 5 and 6'.

Which of the following structures serves as a lung, digestive tract, and kidney for the developing embryo?

zoology reproduction in humans placenta pregnancy and birth fertilization and post fertilization in humans

  1. Placenta

  2. Endometrium

  3. Amnion

  4. Liver

Show answer
Correct Option: A
Explanation:

The placenta is an organ that develops in the uterus during pregnancy. This structure provides oxygen and nutrients to the growing baby and removes waste products from the baby's blood. The placenta attaches to the wall of the uterus, and the baby's umbilical cord arises from it. The organ is usually attached to the top, side, front or back of the uterus.

So the correct option is 'placenta'.

State whether the following statements are true or false .
Endometrium is highly vascular and rich in glands.

zoology reproduction in humans placenta pregnancy and birth fertilization and post fertilization in humans

  1. True

  2. False

Show answer
Correct Option: A
Explanation:
In the uterus, simple tubular glands reach from the endometrial surface through to the base of the stroma, which also carries a rich blood supply provided by the spiral arteries
So, the correct answer is 'True'

Choose the correct answers from the alternatives given.
The placenta

zoology reproduction in humans placenta pregnancy and birth fertilization and post fertilization in humans

  1. is formed by the inner portion of the chorion

  2. contacts a portion of the mothers endometrium

  3. allows the fetus and the mother to exchange nutrients and waste products

  4. all of the above

Show answer
Correct Option: D
Explanation:

The placenta facilitates the supply of oxygen and nutrients to the embryo and also the removal of carbon dioxide and excretory/waste materials produced by the embryo. It is formed from the chorion. 

So the correct option is 'All of the above'.

State whether the following statements are true or false .
The placenta in humans is the true placenta in which foetal and maternal parts can be easily separated without any bleeding.

zoology reproduction in humans placenta pregnancy and birth fertilization and post fertilization in humans

  1. True

  2. False

Show answer
Correct Option: B
Explanation:
The placenta is delivered as part of the afterbirth with a small gush of blood, from a few minutes to a half hour after the baby arrives. The doctor or midwife will examine it to make sure it's intact and that nothing has been left behind in the uterus
So, the correct answer is 'False'

On the basis of intimacy Human placenta is 

zoology reproduction in humans placenta pregnancy and birth fertilization and post fertilization in humans

  1. Interstitial placenta

  2. Deciduate placenta

  3. Discoidal placenta

  4. Yolk sac placenta

Show answer
Correct Option: A