Christmas Biology Exam Practice Test 1

The other options are not applicable to the mangrove ecosystem.

Chloroplasts contain the green pigment, chlorophyll, that is necessary for photosynthesis. Additionally, it gives autotrophic plants their green colour.

Cell D is a neuron, which is specialized for sending and receiving electrical impulses throughout the body.

The first three options are all incorrect. Chloroplasts absorb energy from light, mesophyll cells photosynthesize, and the stoma allow for gaseous exchange and transpiration. However, the last option is correct as the vascular bundle transports water, minerals, and nutrients throughout the plant.

Irritability/Sensitivity is an organisms ability to respond to stimuli.

The nucleus is the "brain" of the cell.

The diagram displays four different types of instruments used for capturing marine species. In The Bahamas, the use of explosives for capturing marine species is illegal.

All cells must respire all the time in order to produce energy to perform cellular functions.

Herbivores are primary consumers and only feed on producers (ie. autotrophic plants).

A population is a group of organisms of the same species in a habitat. All the letters, barring Z, are representing multiple species rather than one species, and therefore, they cannot be considered populations. However, letter Z is representing two striped fish. As such, it can be concluded that these two organisms form a population.

Water moves from high WATER concentration to low WATER concentration. The distilled water has the highest WATER concentration, and as such, water molecules would enter the potato cells (which have a lower water concentration) through the semi-permeable cell membrane, causing the cell to become turgid and increase in length.

Do not get confused with the concentration of the solution. The higher the salt concentration, the lower the water concentration. As such, the answer could not be A, B, or C, as they would have a lower water concentration, resulting in water moving out of the potato cells and the potato cylinders becoming flaccid and weak.

A group of organisms that can produce fertile offspring with one another is called a species. This term refers to a specific category within the biological classification system, indicating organisms that share common characteristics and can interbreed to produce viable offspring. The other options, such as class, family, and genus, refer to broader or more specific categories within the classification system, but they do not specifically indicate the ability to produce fertile offspring.

Sharks, groupers, and dolphins are all vertebrates. The graph shows that there are 7 groupers, 4 sharks, and 2 dolphins on the reef. Therefore, by adding all of these quantities, we come to the conclusion that there are 13 vertebrates in total on the reef.

Osmosis is the movement of water from an area of high water concentration to an area of low water concentration through a semi-permeable membrane. Option D is the only option including water and so it must be the answer.

When the plant is exposed to sunlight, the stomata (which are concentrated in the lower epidermis) open to allow for gaseous exchange. Carbon dioxide levels in the leaf are low as the carbon dioxide is used in photosynthesis, and so the carbon dioxide in the atmosphere moves into the leaf (as materials always move from an area of high concentration to low concentration).

Cell P is a root hair cell. It is specialized to have a larger surface area to increase the rate of osmosis, and as such, the amount of its surface area must be the feature that makes it more efficient in absorbing water than cell Q.

Remember the diagram of the leaf?



































The palisade mesophyll cells are elongated cells specialized for photosynthesis. They are located directly below the upper epidermal cells to receive the most sunlight, and also contain a lot of chloroplasts for photosynthesis. As such, the palisade mesophyll cells must contain the most chloroplasts out of all four options.

The reactants of the process of photosynthesis are carbon dioxide and water. As a result, photosynthesis would remove carbon dioxide out of the atmosphere.

Remember, enzymes are named after the substrates which they break down. The scientific name for "fats" is "lipids". Therefore, the enzyme lipase must break down lipids.

Chloroplasts are small ovoid (oval shaped) organelles where photosynthesis occurs.

Let's go through each option individually.

Option A states that higher light intensity (brighter light) and lower humidity (dry air) decreases the transpiration rate. This is totally incorrect. Brighter light increases the transpiration rate because the stomata open to foster increased photosynthesis through gaseous exchange. Also, the drier air increases the rate of transpiration because the concentration of water is lower outside of the plant, causing increased diffusion of water out of the leaf.

Option B states that higher temperature and lower humidity decreases the transpiration. Yet again, this is totally incorrect. Higher temperature increases the transpiration rate as it allows for water particles to evaporate faster and diffuse out of the stomata. We already have established that lower humidity also increases the transpiration rate.

Option C states that lower light intensity and lower temperature increases the transpiration rate. Once again, this is totally wrong. Lower light intensity would decrease the transpiration rate as the stomata would close as there would be less photosynthesis occurring and so gaseous exchange would be unnecessary. Furthermore, lower temperature would decrease the transpiration rate as the water particles would take longer to evaporate and would be less able to diffuse.

Finally, option D states that higher temperature and higher light intensity increases the transpiration rate. This is the correct option. We have already established that higher temperature and higher light intensity increase the transpiration rate.

Grouper and shark both belong to the fish class, and as such they are most closely related. (NB crawfish is NOT a fish, it is a crustacean.)

Carbon dioxide, chlorophyll, and water are all necessary for photosynthesis.

When naming organisms using binomial nomenclature, the first name always represents the genus and begins with a capital letter. The second name always represents the species and begins with a lower case letter.

Sucrose is the only simple sugar present, and as such it must be the source of carbohydrate for the yeast cells.

Water always moves from high WATER concentration to low WATER concentration. Therefore, liquid X has to be a concentrated solution (meaning that it has a higher concentration of solute and a lower concentration of water) and liquid Y has to be a dilute solution (meaning that it has a lower concentration of solute and a higher concentration of water). The water would move from the dilute solution into the concentrated solution, resulting in the volume of liquid X rising.

Some of you may have thought that the correct answer was excretion because the arrows were pointing the the cow's "dairy air". (get it? LOL) However, you are incorrect. Excretion is getting rid of METABOLIC waste, not undigested food. Metabolic waste is by-products of metabolic processes, such as respiration. (ie. carbon dioxide, urea, etc.) The correct answer would have been nutrition, which is taking in and using food. Digestion falls under this category. And egestion falls under digestion. Egestion is getting rid of undigested food through the cow's "dairy air".

When the barracuda is over-fished, its population decreases. As a result, the number of broad shads would increase. Therefore, the crab population would decrease as its predator's population would have increased. Furthermore, the prickly winkles population would increase as there would be less of its predator.

Each test has a positive result. The biuret test is used to test for proteins, and the positive result is a violet colour. The ethanol test is used to test for lipids (fats), and the positive result is a layer of cloudy white suspension is formed. The Benedict's test is used to test for sugars, and positive results include a blue-green, yellow, orange, brown, or red precipitate is formed.

When leaves lose a lot of water, the cells within the leaf become flaccid and weak in a process know as plasmolysis. They are no longer turgid, and no longer "stand at attention". Instead, they "slouch".

Remember the pyramid of numbers? 









This represents the relative quanitites of each organism (or the number of each organism) at each trophic level. Herbivores are at the second trophic level and can also be called primary consumers. Generally, they have the second highest quantity of all trophic levels. When this is translated to the graph, we see that D has the second highest quantity, and as such, it must be the herbivore. 

Phloem transports sugars from the leaves to the rest of the plant made via photosynthesis. However, when a ring of bark is removed from the tree trunk, the sugars have nowhere to go and so are stored there. This results in a bulge forming. All options regarding xylem are irrelevant as this experiment has nothing to do with xylem. Additionally, you cannot conclude that sugar is being transported in the phloem as you have not tested the bulge to see what is being stored in it. Therefore, option B must be correct as the contents of the phloem are being transported downwards from the leaves to the rest of the tree.