Questions and answers by

iner

Questions (16)

How have scientists learned about the history of life on Earth?A. fossil record B. radioactive dating C. branching trees D. DNA
1. 1 answer
2. 117 views
Eras are subdivided into _____.A. periods B. scales C. records D. calendars
1. 1 answer
2. 100 views
How many pairs of chromosomes are in the body cells of human beings?a.46 b.23 c.over 10,000 d.between 20,000 and 25,000
1. 1 answer
2. 121 views
Which allele combinations are possible for the offspring of two parents that are heterozygous for tall stems (Tt)?a.TT and Tt
1. 1 answer
2. 109 views
The sex cells produced through meiosis each have _____.a.half of the chromosome pairs from the original cell b.one chromosome
1. 1 answer
2. 176 views
How many different genes are contained in a human body cell?a.over 20,000 b.between 1,000 and 2,000 c.23 d.46
1. 1 answer
2. 144 views
Which describes the genes on each pair of chromosomes?a.The alleles must be the same; the genes are in a different order. b.The
1. 1 answer
2. 148 views
which is a characteristic of a capillary?a. carries oxygen-rich blood from the heart to all body parts b. is very wide to allow
1. 1 answer
2. 190 views
At what location does the blood release oxygen and take on carbon dioxide?a. in the veins b. at the lungs c. at the heart d. at
1. 1 answer
2. 103 views
Which describes the function of the cardiovascular system?a. removing solid waste from the body b. carrying oxygen and glucose
1. 1 answer
2. 113 views
Which describes the heart’s pacemaker?a. It sends signals that make the heart expand. b. It removes wastes from the
1. 1 answer
2. 194 views
The upper and lower chambers of the heart are separated by _____.a, septa b. valves c. atria d. ventricles
1. 1 answer
2. 133 views
The small intestine is the part of the digestive system _____.A. where chemicals are produced to break down fat particles B.
1. 1 answer
2. 149 views
Which describes the role of villi?A. They move food along the digestive tract by means of peristalsis. B. They secrete bile that
1. 1 answer
2. 150 views
During peristalsis _____.A. muscles contract involuntarily to move food up and down the esophagus B. muscles contract
1. 1 answer
2. 146 views
Which is the protective substance that lines the stomach?A. pepsin<< B. mucus C. hydrochloric acid D. saliva
1. 5 answers
2. 124 views