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1

Screen shot 2020 06 03 at 10.29.50 am

The image above shows the processes of photosynthesis and respiration. Which organelle is responsible for turning nutrients into energy in animals?

mitochondria

chloroplast

ribosomes

food vacuoles

Explanation

The answer is mitchondria.

Plants and animals are both organisms, meaning that like other living things, they are composed of cells. Both types of cells store food in vacuoles, have cytoplasm, golgi bodies, and ribosomes, but they have a number of distinct differences as well. Animal cells have a membrane and are more irregularly shaped, while plant cells have a cell wall and are rectangular. Additionally, plant cells have organelles called chloroplasts, which aid in the process of photosynthesis.

2

Photosynthesis is:

The process where plants use energy from the sun to create their own food

The process where plants use energy from the sun to make the ground full of more nutrients

The use of chemical reactions to make photographs

The process of animal respiration

Explanation

The answer is "the process where plants use energy from the sun to create their own food."

This process is why plants are referred to as producers. In the process of photosynthesis, the energy from sunlight, carbon dioxide, and water are converted into sugar and oxygen through chemical reactions in plant cells. Animals do not produce their own energy, but have to eat plants or other animals to stay alive. Animals breathe in the oxygen created by photosynthesis and exhale carbon dioxide as a product through their own process called cellular respiration.

3

In this food chain, which species would have the smallest number of individuals?

grass -> grasshopper -> frog -> snake -> hawk

grass

grasshopper

frog

hawk

Explanation

The answer is "hawk."

The transfer of energy in ecosystems occurs when organisms consume one another. Energy is transferred from the organism that is consumed to the organism that does the consuming. A food chain is a representation of this, and shows the “chain” of organisms through which nutrients and energy move.

In a food chain, each organism occupies a different trophic level, defined by how many energy transfers separate it from where the chain begins, with “producers” or “autotrophs” at the bottom, collecting energy from the sun. As you move up the food chain, more and more energy is lost to heat and used by organisms so top predators need to consume more prey to get the same amount of energy from the trophic level below them. Food webs consist of many interconnected food chains and are a more realistic representation of consumption relationships in ecosystems.

4

Elodea chloroplast

What type of cell is pictured in the image above?

a plant cell

an animal cell

a T-Cell

none of these

Explanation

The answer is "a plant cell." The image shows a microscope slide of a plant cell with distinct chloroplasts and rectangular cell walls. Another hint that it's a plant cell, is that the cells and chloroplasts are green!

5

Screen shot 2020 06 03 at 10.29.50 am

The image above shows the processes of photosynthesis and respiration. Which organelle is responsible for turning nutrients into energy in animals?

mitochondria

chloroplast

ribosomes

food vacuoles

Explanation

The answer is mitchondria.

Plants and animals are both organisms, meaning that like other living things, they are composed of cells. Both types of cells store food in vacuoles, have cytoplasm, golgi bodies, and ribosomes, but they have a number of distinct differences as well. Animal cells have a membrane and are more irregularly shaped, while plant cells have a cell wall and are rectangular. Additionally, plant cells have organelles called chloroplasts, which aid in the process of photosynthesis.

6

Where is most carbon on Earth stored?

in rocks and sediments (and dead organisms)

in the atmosphere

in the ocean

in living organisms

Explanation

The answer is "in rocks and sediments"

The carbon cycle describes the flow of the element Carbon in ecosystems. Most carbon is stored in rocks and sediments, while the rest is stored in the ocean, atmosphere, and living organisms. Carbon in the air is absorbed by plants in photosynthesis, consumed by organisms who eat the plants, and then it is returned to the soil when animals die and their organic matter decomposes. The same process happens in oceans with aquatic plants as well. Carbon is also emitted from the burning of fossil fuels which are made from the organic material of organisms that died millions of years ago.

7

Screen shot 2020 06 03 at 2.04.33 pm

What is the function of the Endoplasmic reticulum?

translating and folding new proteins

producing energy in the form of ATP

allowing for photosynthesis

contain the DNA and control activities of the cell

Explanation

The answer is "translating and folding new proteins"

Cell membrane:in animal cells, this separates the interior of all cells from the outside environment (the extracellular space)

Cell wall: in plant cells, gives the cell a rigid rectangular shape, helps to keep the organelles inside the cell, and does not let the cell burst due to changes in pressure.

Chloroplast: in plant cells, allows for photosynthesis, traps energy from sunlight

Endoplasmic reticulum: translation and folding of new proteins

Flagellum: Helps a cell move (not all cells have these)

Golgi apparatus: sorting, packaging, processing and modification of proteins

Mitochondrion: Produces energy in the form of ATP

Nucleus: contains DNA, controls all activities of the cell, performs RNA transcription

Vacuole: stores nutrients, transportation, helps maintain homeostasis

8

Brown fur is dominant to white fur in a species of rabbit and is represented with the alleles "B" and "b".

What are the resulting percentages of genotypes of a cross between a homozygous dominant parent and a heterozygous parent?

50% BB and 50% Bb

75% BB and 25% Bb

50% BB, 25% Bb, 25% bb

100% BB

Explanation

The answer is 50% BB and 50% Bb, as shown in the punnet square below. The phrase "homozygous dominant" means the genotype of one parent is BB while "heterozygous" is a genotype of Bb.
Bbxbb1

9

Suppose a species of insect has 96 chromosomes. How many chromosomes will each daughter cell have after mitosis of an insect cell is complete?

96

192

48

none of these

Explanation

The answer is "96" because the daughter cells will be identical to the parent cells.

Mitosis is a process where a parent cell divides to produce two identical daughter cells. The major purpose of mitosis is for growth and to replace worn out cells. Because the daughter cells contain twice the genetic material of the parent cell, they are referred to as “diploid.”

Some key differences between meiosis and mitosis are: Mitosis involves the division of body cells, while meiosis involves the division of sex cells. Two daughter cells are produced in mitosis, while four are produced in meiosis. Mitosis daughter cells are diploid, but meiosis daughter cells are haploid. Meiosis creates more genetic variation than mitosis.

10

What is eutrophication and how is it caused?

Eutrophication occurs when an aquatic system has an overabundance of nutrients. It is most often caused by human activity like farming, maintaining golf courses and other activities that can lead to fertilizer run off.

Eutrophication occurs when an aquatic system has a lack of nutrients. It is most often caused by human activity like farming, maintaining golf courses and other activities that can lead to fertilizer run off.

Eutrophication occurs when an aquatic system has an overabundance of nutrients. It is most often caused by an excessive amount of bacteria in the soil, performing nitrogen fixation at an increased rate.

Eutrophication occurs when an aquatic system has a lack of nutrients. It is most often caused by an excessive amount of bacteria in the soil, performing nitrogen fixation at an increased rate.

Explanation

The answer is "Eutrophication occurs when an aquatic system has an overabundance of nutrients. It is most often caused by human activity like farming, maintaining golf courses and other activities that can lead to fertilizer run off."

The nitrogen cycle describes the flow of the element nitrogen on Earth. Most of Earth’s nitrogen exists in the atmosphere, but it can be moved into the soil through a process called “fixation.” Fixation usually occurs with the help of bacteria, but can also be done by lightning. Bacteria help nitrites and nitrates change into a form of nitrogen used by plants to help them grow. Animals get their nitrogen by eating plants. Animal waste contains nitrogen but needs to be fixed by bacteria as well. Additionally, when animals die their nitrogen reserves are broken down by decomposers where it can again be used by plants. Denitrification is the process where nitrogen in the soil returns to the atmosphere as a gas.

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