Living Environment – August '23 – Part A

After ingesting Vitamin D, the body converts it into a hormone that is transported throughout the body. This hormone affects cells in the intestines and bones. The reason that this hormone affects only certain cells in the body is because these cells have

• specific receptors

• antibodies

• specific organelles

• genes

Most scientists agree that a large asteroid struck Earth around 65 million years ago. The impact sent large amounts of fine dust particles into the atmosphere, which reduced the amount of sunlight reaching the planet. This event would have the most immediate effect on

• herbivores

• decomposers

• carnivores

• autotrophs

The photic sneeze reflex, an inherited trait, causes some people to sneeze when they are exposed to bright sunlight. In the photic sneeze reflex, the sunlight acts as

• the effect of an environmental factor resulting in a genetic trait

• a biotic factor being passed from parent to offspring

• an environmental factor stimulating a response

• the recombination of genes resulting from sexual reproduction

Difficulties often occur when tissues or organs are transplanted from one person to another because the

• transplanted structures cannot produce new cells

• rate of mitosis differs between the two people involved

• introduction of a foreign substance causes the formation of antibodies

• two people often have the same blood type

In humans, digestion depends on a variety of organs, such as the stomach, small intestine, and liver. The interactions of these organs provide evidence that

• each organ in the human body plays a role in only one life function

• organs in humans work together, resulting in the survival of the individual

• the most important life function in humans is the breaking down of food

• each life function is carried out by at least four different systems in humans

An example of how a plant maintains homeostasis includes

• producing many seeds for reproduction

• controlling the amount of available solar energy

• recycling energy from the Sun

• regulating the action of guard cells

Which is the correct sequence in which these events could occur?

• D – B – A – C

• C – D – B – A

• B – A – C – D

• D – C – A – B

• D – B – A – C

The structures most directly involved in the synthesis of cellular proteins are the

• nucleus and ribosomes

• cell membrane and nucleus

• chloroplasts and cell membrane

• mitochondria and chloroplasts

Hydrangea, a commonly used landscaping flower, can have dramatically different colors, depending on the pH of the soil in which it is grown. The differences in color demonstrate that

• traits can be expressed differently if the environment changes

• flower color is controlled only by genetic information

• abiotic factors do not have an effect on flower production

• pH is the only factor that affects flower growth

Potato plants reproduce both sexually and asexually. Depending on the desired outcome, potato growers use both types of reproduction. A grower would most likely want the potato plants to reproduce asexually when

• selectively breeding new potato varieties

• there is a disease affecting similar potatoes growing in the area

• environmental conditions in the area are changing

• potatoes with the same traits are desired