Systems Physiology - AP Biology

Folds are present in the human brain due to the rapid evolution of brain-related tasks while the skull shape and size remained relatively constant; therefore, folds are present as modifications to limited surface-area-to-volume ratios in the skull cavity.

The cerebellum is mainly responsible for fine tuning the motions of the body, including balance and coordination. As a result, damage to this region would cause difficulty walking straight and maintaining balance.

The medulla oblongata is in the lower half of the brainstem. It controls a variety of functions, mostly involuntary and essential. Heart beat, breathing, and blood pressure are controlled in the medulla oblongata, as is the vomiting reflex.

Speech is controlled by Broca's area, which is located in the frontal lobe of the cerebrum.

Each answer corresponds to one lobe of the cerebrum. The frontal lobe is responsible for conscious thought, as well as many other functions. The parietal lobe is responsible for integrating tactile information. The temporal lobe has the functions of interpreting smell and sound. The occipital lobe is associated with processing visual information.

Folds are present in the human brain due to the rapid evolution of brain-related tasks while the skull shape and size remained relatively constant; therefore, folds are present as modifications to limited surface-area-to-volume ratios in the skull cavity.

Memory B cells circulate the body and are ready to respond to subsequent infections while plasma cells generate many antibodies to a current infect. "Immunoglobulins" refers to both the B cell receptor and to the excreted form of these proteins (known as antibodies). IgG is a class of immunoglobulins (along with IgA, IgE, IgD, and IgM). Finally, macrophages are cells that engulf non-self (and often antibody-bound) cells and communicate with T cells to promote B cell proliferation.

The cerebellum is mainly responsible for fine tuning the motions of the body, including balance and coordination. As a result, damage to this region would cause difficulty walking straight and maintaining balance.

The medulla oblongata is in the lower half of the brainstem. It controls a variety of functions, mostly involuntary and essential. Heart beat, breathing, and blood pressure are controlled in the medulla oblongata, as is the vomiting reflex.

Speech is controlled by Broca's area, which is located in the frontal lobe of the cerebrum.

Each answer corresponds to one lobe of the cerebrum. The frontal lobe is responsible for conscious thought, as well as many other functions. The parietal lobe is responsible for integrating tactile information. The temporal lobe has the functions of interpreting smell and sound. The occipital lobe is associated with processing visual information.

Red blood cells are made in the bone marrow, and live for about 3-4 months. They are enucleated (lacking a nucleus), which makes more space available for hemoglobin molecules, which function to carry oxygen to the tissues. HIV infects T-helper cells, which are white blood cells, not red blood cells. Thus, the name makes sense since the virus infects cells of the immune system (white blood cells) and causes immunodeficiency. The liver and spleen play roles in recycling the red blood cells once they have carried out their function for about 120 days.

Keratinocytes are not immune cells. Rather, they secrete a protein called keratin which is a large proportion of the extracellular matrix and makes up hair, nails, skin, and other parts of the body. All other cells are immune cells.

B-cells produce antibodies (a subset of adaptive immunity called humoral immunity). The usual sequence involves B-cell activation via interleukins from helper T-lymphocytes, which cause the B-cell to undergo mitosis, creating numerous clones that will differentiate into plasma cells (rapid antibody producers) or memory B-cells.

Antibodies (or immunoglobulins) are produced by B-leukocytes and plasma cells, and are a key part of humoral (having to do with bodily fluids) immunity. As such, they can be found in several of the fluids circulating or exiting the body. Some types of immunoglobulins can even cross the placenta or be secreted in breast milk to pass immunity from a mother to her child.

All of the given answer options describe mechanisms for immunoglobulin function.

Neutralization occurs when the antibodies simply cover the biologically active portion of the pathogen, rendering it harmless. Complement fixation refers to the antibodies binding to the pathogen and facilitating the activation of the complement system (a series of plasma proteins that activate other immune processes). Precipitation is when antibodies link the antigens on many pathogens together, creating an insoluble clump ready for removal.

The lymphatic system is responsible for removing excess fluid from the interstitium and returning it to the bloodstream. The fluid will travel through lymph nodes, which monitor for the presence of microbes in the blood. If microbes are present, the lymph nodes will mount an immune response. The lymphatic system also reroutes fat digestates from the small intestine's capillaries and drains them into the veins of the neck. Lymphatic vessels do not assist in the transfer of oxygen to body tissues.

The spleen plays a key role in the immune system as one of the blood filtration centers of the body. It is also involved as a lymphatic organ, allowing filtrates from the blood to be distributed to the body via lymph.

The eye is divided into two chambers by the lens: the anterior and posterior chambers. The anterior chamber is filled with aqueous humor, while the posterior chamber is filled with vitreous humor. Aqueous humor nourishes the eye and maintains intraocular pressure. Aqueous humor is also important in the refraction of light, which allows humans to distinguish clear images and colors.

Hippocratic and Galen humor do not exist. Hippocrates and Galen were two ancient physicians who would use the four humors (yellow bile, black bile, phlegm, and blood) to diagnose and treat patients.

Unmyelinated nervous system components make up grey matter, while myelinated axons make up white matter. The cerebral cortex on the surface of the brain contains unmyelinated neural tissue, namely the cell bodies of neurons in the central nervous system. This region is rich in connections. Below its surface lie many myelinated axon tracts to inner nuclei, the cerebellum, other areas of the cortex, and the spinal cord.

In the blind spot, there is a lack of photoreceptors as the optic nerve exits the optic disk. We normally overcome this automatically when our brains use the information of the surrounding visual field and "fills in" the blind spot.