Download App

Human Reproduction — BIOLOGY STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYHuman Reproduction2 Marks
Question
When and where do chorionic villi appear in humans? State their function.
✓

Answer

Chorionic villi are finger like projections that arise from trophoblast layer that develops in the zygote after it has undergone implantation.
Function of Chorionic Villi:
  1. It interdigites with projections from uterine tissue to from a structure called the placenta, which is the connecting link between the mother and the foetus.
  2. It facilitates the supply of oxygen and nutrients to the embryo.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "Answer the following questions." from Human Reproduction→Human Reproduction — all question types→BIOLOGY STD 12 Science question papers→Maharashtra Board STD 12 Science question papers→Maharashtra Board question paper generator→

Similar questions

Heat loss or heat gain depends upon the surface area of the organism's body. Explain with the help of a suitable example.
OR
Explain, why are small animals rarely found in the polar regions?
→
In Snapdragon, A cross between true breeding red flower $(RR)$ plants and true breeding white flower $(rr)$ plants showed a Progeny of plants with all pink flowers.
  1. The appearance of pink flowers is not known as blending. Why?
  2. What is the phenomenon known as?
→
Principle of vaccination is based on the property of memory' of the immune system. Taking one suitable example, justify the statement.
→

Match cells of immune system in column-I and their functions in column-II and rewrite it.

 column-l column-II
i.Cytotoxic T cells(a)Activation of helper T cells
ii.Plasma cells(b)Blood group antigens
iii.Antigen presenting cells(c)Secretion of perforins
iv.Red blood cells(d)Antibody production
→
How do B-cells direct humoral immunity?
→
A list of three flowering plants is given below. Which ones out of them are:
  1. Monoecious
  2. Bearing pistillate flowers?
List: Date palm, Cucurbits and Pea.
→
Give the location and one function of the following receptors
(i) Mechanoreceptors (ii) Statoacoustic receptors (iii) Baroreceptors
→
The immune system of a person is suppressed. In the ELISA test, he was found positive to a pathogen.
  1. Name the disease the patient is suffering from.
  2. Write the full name of the causative organism.
  3. Which cells of the body are affected by the pathogen.
→
Mention the differences between DNA replication and transcription.
→
Construct a grazing food chain and a detritus food chain using the following, with five links in each:
Earthworm, bird, snake, vulture, grass, grasshopper, frog, decaying plant matter.
→