Test 3 Flashcards
Maintaining a stead-state internal environment, despite changing external environment, is called ____.
homeostasis
How is diabetes linked with homeostasis?
Diabetes results from the body not responding with a negative feedback to the level of glucose in the blood.
There are many organs and glands of the endocrine system, but which one is the master controller?
Hypothalamus
What are hormones?
They are chemicals transported in the blood and affect targeted cells throughout the body.
Which form of diabetes would require regular injections of insulin?
Type 1
Hormones are usually transported through _____ and affect only cells with _____.
blood vessels; specific receptors
Hormones regulate ____.
maturation
reproduction
growth
metabolism
Nonsteroid hormones are derived from _____.
amino acids
A cell that is affected by a particular steroid hormone would be expected to have _____.
a receptor inside the cell that binds the hormone
Which of the following has both endocrine and nonendocrine functions?
pancreas
Which of the following choices does NOT pair an endocrine gland or hormone with an aspect of metabolism that it regulates?
pituitary—-blood potassium levels
Which gland requires the element iodine to produce its hormones?
thyroid
_____ can be a symptom of hypothyroidism.
Goiter
Which of the following may be a consequence of excessive secretion of parathyroid hormone?
loss of calcium from the bone
Which of the following best describes the relatinship of insulin to glucagon?
they are atnagonistic hormones
When the concentration of glucose in the blood rises following the digestion of a meal, what is the hormonal response?
Insulin is released, but not glucagon
What is the metabolic abnormality that underlies the characteristic symptoms of diabetes mellitus, such as a frequent urination?
an inability of the body’s cells to absorb enough glucose from the blood
Which of the following is almost always associated with being overweight and under active?
Type 2 diabetes
Which of the following is a signaling molecule that communicated throughout the body?
hormones
Lactation in nursing mothers is initiated by the hormone oxytocin and regulated by ______.
a positive feedback loop
What may cause hypoglycemia in certain people?
overdose of insulin
excess insulin production
insulinoma
In the negative feeback look of the thyroid, what is the order of steps involved?
- a drop in T3 and T4 occurs
- hypothalamus makes TRH
- Pituitary makes TSH
- Thyroid makes T3 and T4
- T3 and T4 stop the production of TRH and TSH
Ecology is best defined as the study of ________.
the interactions between living organisms and their environment
A population in ecology is defined as _____.
a group of organisms, all from the same species
Which of the following is not an example of an abiotic factor?
bacteria
A dispersion pattern refers to _____.
the spacing of organism throughout a habitat
What is the name of the model of maximum rate of population growth?
Exponential
A sudden natural catastrophe resulting in massive die-offs would be categorized as a density-____ limiting factor.
independent
Which growth model would you expect to see in a stable population?
logistic
What can a human population’s age pyramid tell you about current and future needs?
how many workers will be needed to support retirees and how many schools to build or to close down
Which of these best describes Type 1 surviroship?
low death rate early in life, high death rate late in life
Opporunistic (r-selected) species typically ______.
have a large number of offspring
_____ is the maximum population size that a particular habitat can support.
carrying capacity
In a population that is following a logistic growth pattern, what shape does the population’s growth curve most closely resemble?
S
Which of these factors operates in a density-dependent manner?
food supply
What term should you use for the scientific study of genetics, physiology, evolution, behavior, and the interaction with the environment?
ecology
In terms of age structure, which group will have an immediate effect on the population growth?
reproductive
What carries a signal from one neuron to the next?
neurotransmitter
Hormones derived from amino acids can cause different effects in different cells depending on the type of cell and _____.
its signal transduction pathway
Which of the following is a nonsteroid hormone?
glucagon
Calcitonin is antagonistic to ____.
PTH
An age pyramid with a broad base that quickly slopes up to a narrow top would be indicative of _______.
a developing nation
Human birth rate peaking the 1980s and have been slowly declining ever since. How is this expected to affect our population size over the next several decades?
The human population size will continue to increase, but not as fast as before.
