vestigial organs
A body part that is reduced in size and seems to have no function is typically referred to as a vestigial organ or structure. These may be remnants of evolutionary adaptations that are no longer needed in current organisms. An example in humans is the appendix.
The pelvic girdle in snakes is vestigial because they have lost their hind limbs during evolution. Since snakes no longer have hind limbs, the pelvic girdle serves no functional purpose and is reduced in size and structure.
The semimembranosus muscle in animals is a homologous structure to the hamstring muscles in humans. It functions to flex the knee joint and extend the hip joint in animals, similar to its function in humans. However, there are differences in size and morphology between the animal semimembranosus and the human hamstring muscles.
Pelvic size generally correlates with the size of the animal and varies with the structure of the animal and how it uses it's limbs for locomotion. The size, structure and orientation of a bipedal animal's pelvis is allows for vertical attachments of the bones and muscles of the legs...
Breast size can vary greatly among individuals and is determined by factors such as genetics, hormones, and weight. Breasts typically stop growing in your late teens to early 20s, but changes in size can occur due to factors like pregnancy, weight gain, and hormone fluctuations. Ultimately, the maximum size that breasts can grow varies greatly among individuals.
Vestigial Organs
A homologous structure that is greatly reduced in size is known as a vestigial structure. These structures are remnants of organs or body parts that had a function in ancestors but are no longer used in modern organisms. Examples include the human appendix and the hip bones in whales.
An example of a homologous structure that is greatly reduced in size is the pelvic bone in whales. These bones are remnants of hind limbs found in their land-dwelling ancestors, which have evolved to be much smaller and non-functional in whales due to their adaptation to an aquatic lifestyle.
In adults, the thymus gland is greatly reduced in size. This organ is crucial for the development and maturation of T cells, which are essential for the immune system during childhood. After puberty, the thymus undergoes involution, gradually decreasing in size and functionality, as the immune system becomes more established. As a result, the thymus is significantly smaller and less active in adults compared to children.
Homologous chromosomes are similar in size, shape, and genes. They are typically present in pairs, one inherited from each parent. To determine if two chromosomes are homologous pairs, genetic analysis, such as karyotyping or DNA sequencing, can be performed to compare their structure and content.
A total of 7 homologous pairs are present in 14 chromosomes. Homologous pairs are sets of chromosomes that contain the same genes, one inherited from each parent, and are similar in size and structure.
Homologous chromosomes are a pair of chromosomes, one from each parent, that have the same genes at the same loci. They share similar genetic information, but may have different versions of the same gene called alleles. Homologous chromosomes also have similar size and structure.
With time, if an organ or structure is no longer needed, natural selection may reduce the size of the organ until it completely disappears from the species or is very reduced in size. It is suggested that some vestigial organs may remain in a reduced state because they have a minor function within the body.
A film on which printed materials are photographed at greatly reduced size for ease of storage. A reproduction on this kind of film.
Phys
The screen size the the exact same. However, the thickness is greatly reduced in the iPad 2 making it lighter as well.
In prophase I of meiosis, two pairs of homologous chromosomes would consist of four chromosomes total. These chromosomal pairs are similar in size, shape, and genetic content. During prophase I, homologous chromosomes will undergo synapsis to form a structure called a tetrad.