The first vascular plants evolved during the _____ period.

A. Silurian

B. Carboniferous

C. Cambrian

D. Ordovician

E. Devonian


A. Silurian

Biology & Microbiology

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Answer the following statements true (T) or false (F)

1. Arginine vasotocin is found in nonmammalian vertebrates and shares structural and functional properties with antidiuretic hormone and oxytocin. Because of this, it is generally thought that arginine vasotocin was the ancestoral posterior pituitary hormone in vertebrates. 2. Vitamin D is a hormone produced in part by exposure to sunlight. 3. If blood sodium levels rise sharply above normal limits the heart will release more atrial natriuretic peptide. 4. Juvenile hormone is a critical growth regulatory and maturity hormone in people. 5. A growth-hormone releasing hormone tumor in the brain could lead to stunted growth in children.

Biology & Microbiology

A surrogate mother can help couples have a child when the woman does not have a functional

A) uterine tube. B) vagina. C) cervix. D) uterus.

Biology & Microbiology

The contractile unit of a skeletal muscle fiber

is a(an) ___.

a. myofibril b. sarcomere c. myosin filament d. actin filament e. Z line

Biology & Microbiology

The reverse of a dehydration synthesis reaction is a(n) ________ reaction.

A. anabolic B. exchange C. hydrolytic D. endothermic E. metabolic

Biology & Microbiology