cells

A cell, the basic unit of living things, contains microscopic structures called organelles. A

group of specialized cells of the same type forms a tissue, such as muscle or nerve tissue.

An organ such as the liver is composed of different kinds of tissues that contribute to its

overall function. A group of related organs form an organ system, such as the digestive

system. A living organism may contain a number of organ systems working together to

carry on the life functions.

Based on the information, in which category does the human heart belong?

• cell

• tissue

• organ

• organ system

Uma wanted to test her hypothesis that fescue grass grows best under red light.

Independent variables, such as size of fescue grass plants, soil type, number of plants, and

length of exposure to light were kept identical for both the experimental and control groups.

Uma exposed the experimental group to red, green, and blue light and the control group

only to sunlight. She took daily measurements of plant height for the next three weeks.

During the second week, Uma noticed that 8 of the 10 plants that she had exposed to red

light looked a little wilted. She increased the daily water amount for these 8 plants. At the

end of the experiment, she concluded that fescue grass grows best under red light.

What is a possible flaw in Uma’s experiment?

• keep track of plant growth under each treatment

• give equal amounts of water to all plants

• monitor the plants in the control group

• plant all samples in the same type of soil

Scientists’ studies have revealed that health is tied very closely to diet. Health

organizations estimate that more than one-third of all cancer is caused by food and drink.

The health of the heart and circulatory system is linked to these factors and to the amount

of cholesterol in the bloodstream.

Cholesterol is a fatty, waxy substance. Although a certain amount is required for good

health, excessive amounts of cholesterol cause arteries to clog.

Which meal and beverage is best for a person who is trying to reduce his or her cholesterol

level?

• cheese sticks, pears, salad, milk

• hamburger, french fries, cola

• pinto beans, plain baked potato, apples, tea

• steak, green beans, rice, coffee

The sugars and starches in the human diet are broken down into glucose in the digestive

system. This glucose passes from the small intestine into the blood. Human blood glucose

levels are regulated by two hormones produced by the Islets of Langerhans in the human

pancreas. The hormones are insulin, which lowers the level of blood glucose, and glucagon, which raises it.

Which statement best describes what happens after one eats a meal high in sugar and

starches?

• The insulin level in the blood increases

• No hormonal changes occur.

• The insulin level in the blood remains about the same

• The insulin level in the blood decreases.

There are usually thirty-two teeth in the mouth of an adult human. They are divided into

four groups: incisors, canines, premolars, and molars. The diagram below shows the

arrangement of these teeth in the mouth.

Which statement best explains why your teeth have so many shapes?

• The different shapes allow all of the teeth to fit in your mouth.

• Each tooth has a specialized biting or chewing function.

• Teeth allow you to swallow more effectively.

• All the teeth in your mouth are used for the same purpose

The nightshade family of plants includes more than 2000 species of herbs, shrubs, and

small trees. Plants with edible parts include the potato, tomato, eggplant, and red pepper.

Some nightshade members such as jimsonweed and belladonna contain poisonous

substances. Tobacco and petunias are also in the nightshade family.

Which of the following most accurately describes the entire group of plants in the

nightshade family?

• poisonous plants

• edible plants

• a large variety of species

• no economically important species

Blood typing is essentially a chemical reaction that provides data so that blood may be

safely transfused from one person to another. The basic objective is to avoid “clumping”

that could occur in the recipient when the wrong blood type is received. These “clumps” of

red blood cells could block arteries or veins affecting the blood flow to critical body organs,

like the heart or the brain.Based on the chart and the information, which blood type will not form clumps with either

Anti-A reagent serum or the Anti-B reagent serum?

• Types A and B

• Type O

• Type AB

• Type B

Adults generally breathe in and out 12 to 20 times per minute. People sitting down breathe

more slowly than those standing up. The older adults become, the more slowly they

breathe. Children breathe twice as fast as adults. Women generally breathe faster than

men.

Which of the following persons would most likely breathe the slowest?

• a 10-year-old girl standing up

• 15-year-old boy sitting down

• a 50-year-old man sitting down

• a 50-year-old woman standing up

All living things are made up of...

• cells
• cell tissues
• organ
• organ systems

Tags

NGSS.MS-LS1-1

NGSS.MS-LS1-3

What distinguishes a plant cell from an animal cell? (How do you tell them apart) Hint: There's 3 ways (Check all 3)

• Central Vacuole

• Mitochondria

• Cell Wall

• Ribosomes

• Chloroplasts

Tags

NGSS.MS-LS4-2