Most accurate statement of why cells stay small:
Surface area of a cell must heed exchange requiremens
restores the amount of surface area needed for exchange requirements in developing embryos such as a chick
The statement that best describes cell theory:
All living things are make of cells and cells come only from pre-existing cells
the semi-fluid internal medium of a cell that dissolves molecules between the nucleus and cell membrane.
The function of the plasma membrane is:
A. Determines which substances enter and leave the cell. B. serves as a boundary between the cell and its environment. C. contains receptor sites which determine how the cell interacts with its environment.
Cell division is important as related to the size of cells because:
Cell division restores the amount of surface area needed for exchange requirements
In an isotonic solution the number of particles is equal:
CORRECT statement about solute concentrations or particles inside and outside the cell
The assisted transport of a molecule across the cell membrane without an expenditure of energy
Example: an amoeba feeding by engulfing is prey with its false feet or pseudopods. As a WBC does to pathogen
The rough endoplasmic reticulum is important in the synthesis of _____________ and the smooth endoplasmic reticulum is important in synthesizing _____________.
Functions of the integument
protection from pathogen invasion, inhibition of water loss, regulation of body temperature, synthesis of vitamin D
Accessory organs of the integument
Nails, hair, and glands are all structures of the epidermal origin.
The most correct statement concerning capillaries:
The only site of nutrient, gas exchange, and waste exchange is the capillaries.
Correct statements regarding the heart:
The heart is cone-shaped, is about the size of a human fist, normally tilted toward the left, is between the lungs.
_______pressure occurs when the ventricles are relaxing and _______occurs when the heart ejects blood.
The major function(s) of blood includes:
transporting oxygen, hormones, and nutrients; carrying waste products; regulating body temperatures and pH; fighting pathogens.
found in red blood cells; an oxygen transporter; required for cellular respiration; the pigment that makes blood red.
exist in some bacteria and prevent them from being destroyed boy phagocytic WBC and certain one-celled organisms
Under ideal conditions, some species of bacteria can double their numbers every 12 minutes. This ability is the result of bacteria being capable of___________.
The thymus becomes smaller with age as well as ___________.
helps T lymphocytes learn self from nonself
Unfortunately many people think all bacteria are bad, identify the positive contributions of some bacteria (all are correct)
bacteria can serve as decomposers in the environment, bacteria are important in the wine, cheese and bread industry, bacteria are important in biotechnology, some bacteria are beneficial residents of the digestive tract
The following statements that most accurately describe viruses:
They contain a protein coat called a capsid, they may contain genomic DNA or RNA, They are acellular, they are obligate intracellular parasites.
Viruses are capable of multiplying in a host cell because:
viral DNA instructs the cell to produce more of the virus.
New viral pathogens emerge when:
they are transported to different parts of the world, the virus mutates, the virus can be transmitted by a new vector, the immune system cannot recognize a change in the virus.
The lymphatic system:
takes up excess tissue fluid and returns it to the bloodstream; absorbs fats in the intestines; helps the body defend against disease; includes the spleen, thymus, and tonsils
Red bone marrow an the __________are considered primary lymphatic organs and lymph nodes and the ______are considered secondary lymphatic organs.
The following are considered nonspecific defenses:
barriers to entry; inflammatory reaction; natural killer cells; protective proteins
in _____immunity the individual produces antibodies against particular pathogens and in ______immunity the individual is given specific antibodies against a pathogen.
After being exposed to a contagious disease, Jennifer has accumulated a high level of antibodies, yet shows no sign of illness. She is exhibiting: