Human Embryology Week 6

<p>Septation of the atria and ventricles (C)</p> Signup and view all the answers

<p>Development of nostrils and nasal cavities (D)</p> Signup and view all the answers

<p>Lower jaw and chin (A)</p> Signup and view all the answers

<p>Coordinated contractions can be observed via ultrasound (C)</p> Signup and view all the answers

<p>Definition of limb buds (A)</p> Signup and view all the answers

<p>They form paddle-like hand plates. (A)</p> Signup and view all the answers

<p>To sculpt and separate the digits. (A)</p> Signup and view all the answers

<p>Formation of hand plates. (B)</p> Signup and view all the answers

<p>Beginning of finger segmentation. (C)</p> Signup and view all the answers

<p>They lag slightly behind in differentiation. (B)</p> Signup and view all the answers

<p>Foundation for digit formation. (A)</p> Signup and view all the answers

<p>It begins to herniate into the umbilical cord. (C)</p> Signup and view all the answers

<p>Flattened distal ends of lower limb buds. (D)</p> Signup and view all the answers

<p>Parts of the small intestine (B)</p> Signup and view all the answers

<p>Counterclockwise (D)</p> Signup and view all the answers

<p>Yolk sac via the vitelline duct (D)</p> Signup and view all the answers

<p>It forms the large intestine (A)</p> Signup and view all the answers

<p>The umbilical cord (D)</p> Signup and view all the answers

<p>It ensures proper organ positioning within the abdominal cavity (B)</p> Signup and view all the answers

<p>Week 6 (C)</p> Signup and view all the answers

<p>It acts as a conduit for nutrients and waste exchange (B)</p> Signup and view all the answers

The formation of two separate chambers in the heart, the right and left ventricle, through the development of the interventricular septum.

During the 6th week, the upper jaw and cheeks form as the maxillary processes expand inward.

The first stage of nostril development, these depressions appear on the frontonasal prominence during the 6th week.

The process during the 6th week where the heart develops a more defined structure and becomes functional.

The initial separation of the right and left atria through the growth of the septum primum and septum secundum.

This opening allows blood to flow directly from the right atrium to the left atrium, bypassing the fetal lungs which are not yet functional.

During week 6, the limb buds develop further and segments for fingers begin to form.

The fusion of two mandibular processes during the 6th week to form the lower jaw and chin.

The distal ends of upper limb buds flatten into paddle-like structures during week 6, forming the precursors to the hands. These structures are essential for further limb differentiation.

Thickened ridges appearing in the hand plates indicate the future location of fingers. They serve as a blueprint for digit segmentation and help organize the fingers.

Programmed cell death, or apoptosis, eliminates tissue between the digital rays, sculpting individual fingers. It plays a crucial role in shaping the digits.

The lower limbs show slight elongation and differentiation by week 6, but develop slightly later than the upper limbs. The foot plates, the precursors to the feet, begin to form during this stage.

The midgut elongates rapidly and forms a loop that pushes into the umbilical cord to accommodate its growth, due to limited space in the abdominal cavity.

The midgut extends outward into the umbilical cord as it grows, creating a temporary hernia.

The midgut, the portion of the developing gut that will become the small and large intestines, grows rapidly and protrudes out of the abdominal cavity into the umbilical cord.

The temporary connection between the herniated midgut and the yolk sac is called the vitelline duct. It serves as a passage for nutrients and waste.

The upper part of the herniated midgut loop develops into the duodenum, jejunum, and part of the ileum, responsible for nutrient absorption.

The lower part of the herniated midgut loop forms the cecum, appendix, and part of the colon, responsible for water absorption and waste processing.

The midgut loop rotates 90 degrees counterclockwise around the superior mesenteric artery (SMA) during the 6th week, placing the intestines in their proper position.

The initial 90-degree counterclockwise rotation of the midgut loop around the superior mesenteric artery.

The cranial limb of the midgut loop moves to the right side of the body, while the caudal limb moves to the left.

The superior mesenteric artery (SMA) serves as the axis around which the midgut loop rotates, ensuring correct anatomical positioning of the intestines.