Athabasca University (AU ) • Biology

Which of the following is NOT a way the normal microbiota of the intestine helps to prevent infection? a. It produces acids that lower the pH of the stomach. b. It speeds up the process by which microbes are flushed from the digestive tract. c. It consumes food and occupies space, outcompeting potential pathogens. d. It generates large quantities of oxygen that kill anaerobic pathogens. d What types of microbes live in the intestines? a. Diverse species of bacteria, archaea, and fungi, es...

Which organs produce the gametes in the male? Are they primary or secondary sex organs? Why? Testes. Primary (gonads). Primary sex organs are those that produce the gametes (sperm). Is the penis a primary or secondary sex organ? Why? Secondary, since it does not produce the gametes but is it necessary for reproduction. What are the male gametes called? Sperm What is the scrotum? Which organ(s) does the scrotum contain? It is a pendulous pouch of skin, muscle, and fibrous connective tissue...

cell membrane (plasma membrane) phospholipid bilayer that surrounds all cells and regulates what enters and leaves the cell eukaryote A cell that contains a nucleus and membrane bound organelles nucleoid A non-membrane-bounded region in a prokaryotic cell where the DNA is concentrated. nucleus A part of the cell containing DNA and RNA and responsible for growth and reproduction prokaryote A unicellular organism that lacks a nucleus and membrane bound organelles amyloplast Unpigmented ...

1 T/F: The first and second lines of defense are considered nonspecific resistance while the third line of defense is considered adaptive immunity. true 2 The ability to ward off a specific infection or disease, usually as a result of prior exposure and the body's production of antibodies or lymphocytes against one pathogen, is called __________. adaptive immunity 3 If a person is sick with the common cold on May 1st, gets well, and then memory cells are exposed to the same virus o...

1 Biodiversity is recorded ____ but interpreted ___. Through what kind of observations? recorded locally and interpreted globally. Through direct observations. 2 As habitat increases, what happens to # species observed? How is this modeled? Species # observed increases. Modeled via species-area curves 3 Biogeography is the global ____ of ___ and ____. global distribution of lineages and biodiversity 4 Who is the father of biology? What did he do importantly? What two patterns rel...

1 The search for natural explanations of natural phenomena is known as: Science 2 Which of the following are qualities of any good scientific hypothesis? I. It is testable. II. It is falsifiable. III. It produces quantitative data. IV. It produces results that can be replicated. I. It is testable II. It is falsifiable 3 Agrobacterium infects plants and causes them to form tumors. You determine that tumor formation requires a large amount of the plant's energy for tissue forma...

1 aneuploidy Change in chromosome number of less than an entire genome 2 chromosome mutation rearrangements (loss/gain) of large pieces of DNA 3 crossing over exchange of chromatid segments of two adjacent homologous chromosomes during meiosis 4 directional selection selection for one extreme against the other extreme 5 disruptive selection selection for BOTH extremes against the average/median condition 6 fitness a measure of the relative contribution of a given genot...

Anatomy Biological FORM of an organism Physiology Biological FUNCTIONS an organism performs Adaptations for increasing surface area - In vertebrates, space between cells is filled with interstitial fluid for exchange of material - Complex body plans include circulatory fluid (eg. blood) Organization of animal bodies cells -> tissues -> organs -> organ systems Epithelial tissue - Lines the surface of the body, organs, and body cavities - Cells are closely joined Connective ti...

1 quantitative Numbers are needed in order to obtain __________ data 2 B Here is a false statement: A 19-year-old W&M student travels to Belize on a study abroad program and finds that her skin darkens due to production of the pigment melanin. The student has evolved. Which of the following statements correctly revises the incorrect statement? A. The student had the capacity to produce melanin and has acclimated in response to the new environmental conditions. The student's genotyp...

•circulatory- transport materials between cells of body •digestive- breaks down food to be transported into body •endocrine- coordination of body function •immune- defend against foreign invaders •integumentary- protect against external environment •musculoskeletal- support and movement of body •nervous- coordinate body function using electrical signal •reproductive- to reproduce •respiratory- bringing air in and out of the body •urinary- waste removal; maintain wate...