Biology Final: unit 1

UNIT 1: Approved eye protection devices (such as goggles) are worn in the laboratory

any time chemicals, heat or glassware or used

UNIT 1: Describe the difference between positive and negative feedback, using the words "stimulus" and "response" in your answer.  Your answer should be written in complete sentences.

negative feedback responds to a condition and brings it back to its normal point, positive responds to the stimulus and goes in a cycle of repeating steps. negative goes from A(not normal condition) to B(shivering/sweating) to C(normal condition). positive goes from A(not normal condition) to B(response to the condition) to A and B again until at one point it stops and returns to homeostasis.

UNIT 1: Responding to their environment is a characteristic of all living things. Which of the following is NOT an example of response to the environment?

• Leaves of plants track the movements of the sun during the day.

• b. A houseplant, when placed near a window, bends its stem to face the sun.

• c. The pupils of the human eye dilate in a dark environment.

• d. Touching a hot stove causes the hand to quickly move away.

• Organs are composed of tissues, and each tissue contains groups of similar cells.

Organs are composed of tissues, and each tissue contains groups of similar cells.

UNIT 1: Cows spend most of their day in the field eating grass. Grass is their primary source of food energy. In fact, cows have adapted to eating grass (which is hard to digest) by having multiples stomachs. Cows spend almost all of their time on their feet (even when they are sleeping), but when it is about to rain, cows will often lay down in the field.  Using only the information provided here, what characteristics of life do the cows demonstrate?

adapt to the enviorment, repsond to the enviorment, have a need for material and energy

UNIT 1: When a blood vessel is damaged, platelets start to cling to the injured site and release chemicals that attract more platelets. The platelets continue to pile up and release chemicals until a clot is formed. This is an example of

positive feedback

UNIT 1: The two types of feedback that help organisms maintain homeostasis are?

positive and negative

UNIT 1

B

Classify the following as positive feedback, negative feedback, or both:

1.Your body temperature rises as you walk around outside in Bangladesh on a hot afternoon. The sensors in your skin detect the rise in your surface temperature so you start to sweat.

2. Some organisms have internal feedback systems, physiological changes occurring prevent breeding when population densities are high and promote breeding when population densities are low.

3. A thermostat in a central heating system can determine the temperature of your living room. It switches the air conditioner on when the temperature increases to a predetermined level and shuts it off when it cools to another level. The room temperature remains within a comfortable level regardless of the temperature outside.

4. in some developing countries poverty causes illness and contributes to poor standards of education. In the absence of knowledge of family planning methods and hygiene, this contributes to population growth and illness, adding further to the causes of poverty; “a vicious circle of poverty.”

1. negative

2. negative

3. negative

4. positive

It’s okay to pick up broken glass with your bare hands as long as the glass is placed in the trash.

false

If you do not understand a direction or part of a lab procedure, you should

ask the instructor before proceeding

An acorn seed becomes a seedling before it is an oak tree. This is an example of which characteristic of life?

living things grow and develop

homeostasis…

is the maintenance of a relatively stable internal environment and often incorporates a form of feedback regulation

Which of the following is NOT a characteristic of all living things?

• a. Growth and development

• . Ability to move

• c. Response to the enviornment

• d. Ability to reproduce

abilility to move

All unknown chemicals in the lab should be considered:

dangerous

The level of glucose in the blood is kept within a very narrow range. A blood glucose level outside of this range stimulates the pancreas to release insulin. The effect of insulin is to

raise blood glucose levels, which increases insulin production.

The body temperature of humans fluctuates only slightly during the day. This is an example of which characteristic of life?

Living things carry out homeostasis.

Graduated cylinders measure mass.

false

Levels of Organization: Place the following term in order from simplest concept to most complex concept

1. atom

2. :molecule.

3. cells

4. :tissues

5. organs .

6. organ systems.

7. organism.

8. :species

9. population

10. community

11. ecosystem

12. biosphere

Insulin is a hormone produced by the pancreas and helps to regulate the concentration of __________ in the blood.

glucose

What lab equipment is used for holding and organizing test tubes on the laboratory counter? Also a good place to store test tubes while they dry

test tube rack

Thermoregulation is a specific type of homeostasis where certain higher animals must maintain their internal body temperature. Thermoregulation and other control mechanisms all use __________ feedback to maintain control.

negative

A housefly has offspring that soon replace the parents. This is an example of which characteristic of life?

living things reproduce

Read the information given below about a scientific investigation.  Identify the four Science and Engineering practices that are found in the investigation.

A researcher wanted to determine if a new anti-anxiety drug decreased anxiety levels. Three hundred patients were given the new drug and three hundred patients were given a placebo (also known as a “sugar pill” that does not contain any medicine). All of the patients were told they were receiving the new drug and were monitored for six months. At the end of the six months, all of the patient information was analyzed and the researcher concluded that because the patients given the placebo indicated the same reduction in anxiety as the patients given the new drug, the new drug was ineffective in decreasing anxiety levels.

analyzing and interpreting data-

planning and carrying out investigations-

obtaining, evaluating and communicating information-

engaging in arguments using evidence

In order to conserve body heat, the body will react to maintain homeostasis. Identify one way in which the body will react.

shivering

1. a small and extremely sharp bladed instrument used for surgery, anatomical dissection, and various arts and crafts

2. a common piece of laboratory equipment used to measure the volume of a liquid. It has a narrow cylindrical shape. Each marked line represents the amount of liquid that has been measured.

3. A thin flat piece of glass used to hold objects for examination under a microscope.

4. are a handheld, hinged instrument used for grasping and holding objects

5. A simple container for stirring, mixing and heating liquids commonly used in many laboratories. They are generally cylindrical in shape, with a flat bottom.

1. scalpel

2. gradualated cylinder

3. microscope slide

4. forcps

5. beaker