Exam #1 Review (Ch. 1, 5, 6)

Prokaryotes are classified as belonging to two different domains. What are they?

• Bacteria & Protista
• Bacteria & Archaea
• Bacteria & Eukarya
• Archaea & Protista

Plant cells have ___ for cell to cell communication.

• gap junctions
• plasmodesmata
• desmosomes
• tight junctions

Which structure is common to plant and animal cells?

• central vacuole
• chloroplast
• wall made of cellulose
• mitochondrion

White blood cells engulf bacteria through what process?

• pinocytosis
• osmosis
• phagocytosis
• exocytosis

Large numbers of ribosomes are present in cells that specialize in producing which of the following molecules?

• glycogen
• cellulose
• proteins
• lipids

All of the following are part of a prokaryotic cell except

• a plasma membrane
• DNA
• an endoplasmic reticulum
• ribosomes

Positive feedback differs from negative feedback in that

• positive feedback systems have control centers that are lacking in negative feedback systems.
• the positive feedback's effector responses are in the same direction as the inititiating stimulus producing an intensified response.
• positive feedback benefits the organism, whereas negative feedback is detrimental.
• the effector's response increases some parameter,such as body temperature, whereas in negative feedback it can only decrease the parameter.

At puberty, an adolescent female body changes in both structure and function of several organ systems, primarily under the influence of changing concentrations of estrogens and other steroid hormones. How can one hormone, such as estrogen, mediate so many effects?

• Estrogen is kept away from the surface of any cells not able to bind it at the surface.
• Estrogen binds to specific receptors inside many kinds of cells, each of which have different responses to its binding.
• Estrogen has specific receptros inside several cell types, but each cell responds in the same way to its binding.
• Estrogen is produced in very large concentration and therefore diffuses widely.

The body's automatic tendency to maintain a constant and optimal internal environment is termed

• estivation.
• homeostasis.
• physiological chance.
• static equilibrium.

Which term most precisely describes the cellular process of breaking down large molecules into smaller ones?

• anabolism
• catabolism
• metabolism
• dehydration