Elastin Metabolism and Composition

What does the ATP7A gene provide instructions for making?

Elastin cutis laxa forms

Supravalvular aortic stenosis (SVAS)

A protein important for regulating copper levels in the body (correct)

A protein involved in the formation and function of elastic fibers

How are autosomal recessive forms of cutis laxa generally compared to the autosomal dominant form?

They have a different pattern of inheritance

They have similar severity levels

They tend to be more severe (correct)

They are less severe

What is the X-linked form of cutis laxa often referred to as?

Supravalvular aortic stenosis (SVAS)

Occipital horn syndrome (correct)

Acquired cutis laxa

Menkes syndrome

Which gene is associated with causing Supravalvular aortic stenosis (SVAS)?

ELN gene Signup and view all the answers

What effect can aortic narrowing, caused by SVAS, have on the heart?

Lead to shortness of breath, chest pain, and heart failure Signup and view all the answers

Which condition is considered a mild type of Menkes syndrome?

Occipital horn syndrome Signup and view all the answers

Which pigment found in the skin resembles melanin but is diffusely present throughout the epidermis?

Melanoid Signup and view all the answers

What polymer is eumelanin composed of?

Dihydroxyindole carboxylic acids and benzothiazine units Signup and view all the answers

Which pigment is largely responsible for red hair and freckles?

Pheomelanin Signup and view all the answers

What is the precursor of melanin synthesis?

L-tyrosine Signup and view all the answers

Which organ of the human body is affected by melanin synthesis?

Skin Signup and view all the answers

What is the characteristic color of Hemoglobin?

Purple Signup and view all the answers

What is the half-life of elastin in the human body?

74 years Signup and view all the answers

How many tropoelastin gene(s) exist in humans?

One Signup and view all the answers

What enzyme catalyzes the reaction of linking soluble tropoelastin protein molecules to form elastin?

Lysyl oxidase Signup and view all the answers

Which disease is characterized by loose, sagging skin, aneurysm risk, and emphysema?

Cutis laxa Signup and view all the answers

What is the main role of lysyl oxidase in elastin metabolism?

Catalyzing cross-linking in elastin formation Signup and view all the answers

What type of genetic pattern is associated with Williams syndrome?

Autosomal dominant Signup and view all the answers

Which gene is associated with Williams syndrome?

ELN Signup and view all the answers

Why do people with Williams syndrome have connective tissue abnormalities?

Loss of ELN gene Signup and view all the answers

Which gene is responsible for encoding fibrillin-1 protein in Marfan syndrome?

FBN1 Signup and view all the answers

What is the main role of the Fibrillin-1 protein in Marfan syndrome?

Proper formation of extracellular matrix Signup and view all the answers

Which genetic disorder is characterized by being unusually tall with long limbs and thin fingers?

Marfan syndrome Signup and view all the answers

What is the likelihood that the replacement base in the excision repair process is the same as the base that was removed?

1 in 4 Signup and view all the answers

How does excision repair impact the risk of developing skin cancer?

Introduces DNA mutations Signup and view all the answers

What role does melanin play in protecting the skin from UV rays?

Absorbing UV rays Signup and view all the answers

What is the photochemical process that converts UV-photon energy into heat called?

Internal conversion Signup and view all the answers

What harmful outcomes can result if UV-photon energy is not converted into heat?

Generation of free radicals Signup and view all the answers

How does natural skin color impact photoprotection?

Darker skin provides more photoprotection due to increased melanin Signup and view all the answers