Biology Unit 4

Facilitated diffusion requires a _____ carrier to aid in membrane traffic.

Protein

Which of the following statements correctly describes the concept of homeostasis?

Homeostasis is a process in which cells maintain a stable internal environment.

Match each organelle to its corresponding description. destroys unwanted materials in the cell

lysosomes

Match each organelle to its corresponding description. determines what enters and exits the nucleus

nuclear envelope

Selectively permeable membranes allow ______.

only certain molecules to pass through

Different molecules are mixed into the phospholipid bilayer to aid in different functions. Match each molecule to the function it provides. cholesterol

strength

Put the steps of a basic control system in order (order 1-4). control center

2

Put the steps of a basic control system in order (order 1-4). communication system

3

Put the steps of a basic control system in order (order 1-4). target

4

Feedback loops are _____ systems of information.

Closed

Different molecules are mixed into the phospholipid bilayer to aid in different functions. Match each molecule to the function it provides. Carbohydrate

Communication

Which of the following is a response to an external stimulus?

Migration

Which of the following is true of active transport?

Molecules called pumps function to control active transport.

Which type of cells thrive in an isotonic solution?

Animal cells

Some molecules require the cell to use energy for movement across the membrane. This is called _______.

active transport

Match the stimulus to an animal's corresponding response. thirst indicates a loss of fluid

search for water and drink

Put the steps of a basic control system in order (order 1-4). sensor

1

Which of the following statements is true of a hypertonic solution?

A solution is hypertonic when the concentration of dissolved particles is higher outside of the cell than it is inside of the cell. This means the water concentration is higher inside the cell.

Which of the following terms refers to the movement of materials through a cell membrane by using the cell's energy?

Active transport

Which of the following is not true of lactation?

After childbirth, a woman automatically begins to lactate.

Which of the following is not a method of thermoregulation?

Deep breathing

Identify the similarities between facilitated diffusion and simple diffusion.

Both are processes of molecules moving through the cell membrane Neither requires the cell to use any energy Materials move from areas of higher concentration to areas of lower concentration

The random movement of molecules is referred to as _______.

Brownian Movement

A jackrabbit is a warm-blooded animal that lives in the desert. In the desert the temperature is over 110 degrees during the day. How can the jackrabbit maintain thermoregulation?

By releasing excess heat through its oversized ears

Why are control systems found in the body?

Control systems work to maintain homeostasis by collecting data via sensors, transmitting the data to control centers, and sending communications to targets within the body to cause a response.

Which of the following are examples of passive transport?

Diffusion Osmosis Facilitated diffusion

The parasympathetic nervous system is responsible for getting your body back to its normal state after a perceived threat has passed. Which of the following is not a response of the parasympathetic nervous system?

Dilation of pupils

_____ is the process used by an amoeba to excrete waste.

Exocytosis

Match the stimulus to an animal's corresponding response. Pain lets an animal know it is injured or about to be injured

Finds somewhere to hide until healed

Match each organelle to its corresponding description. packages and ships material

Golgi complex

Which of the following is not regulated by homeostasis?

Height

A cell with 25% particles is placed in a solution with 55% particles. The solution has what type of tonicity?

Hypertonic

Submersion in which type of solution is best for plants, because it causes high turgor pressure?

Hypotonic

Which of the following scenarios can be classified as a negative feedback loop?

Increase in blood pressure to reduce heart rate

In a positive feedback loop, the response to the signal _____ the original signal.

Increases

Which of the following statements describes the structure of the plasma membrane?

It is a lipid bilayer with the hydrophobic area pointing inward, and the hydrophilic area facing outward.

What is the response of an ectotherm, such as a lizard, when it encounters cold temperatures?

It will move to a warmer spot

Which organ(s) plays a major role in maintaining homeostasis when toxins build up in the body?

Kidneys

Which of the following is not an example of a negative feedback loop?

Labor in childbirth

_____ move around the cytoplasm, and digest substances that do not belong, or are no longer needed.

Lysosomes

How are membrane receptors different from intracellular receptors?

Membrane receptors are located on the outside of the cell, while intracellular receptors are found on the inside.

During labor in childbirth, what is the next step of the positive feedback loop below? 1. Contractions push the fetus against the cervix. 2. The cervix begins to dilate. 3. Dilating triggers the production of the hormone oxytocin. 4. _____

More frequent, stronger contractions begin

Which of the following is not true of negative feedback loops?

Negative feedback loops are temporary.

The sodium-potassium pump is vital to the proper function of which body system?

Nervous

Which of the following is not an example of active transport?

Osmosis

Facilitated diffusion is an example of _____ transport.

Passive

_______ is the movement of molecules across a membrane without the cell expending any of its own energy.

Passive transport

Match the stimulus to an animal's corresponding response. When an animal sees a potential mate

Performs a courtship dance or song

_____ occurs when the cell membrane surrounds and engulfs large particles, such as white blood cells engulfing bacteria.

Phagocytosis

You sustain a paper cut. Platelets arrive at the site and release chemicals that attract more platelets. Platelets continue to arrive until a clot has formed. What type of feedback is this?

Positive

How do positive and negative feedback loops differ?

Positive feedback loops increase the initial signal, while negative feedback loops decrease the original signal.

Match the stimulus to an animal's corresponding response. When an animal sees a predator

Run away or hide

Different molecules are mixed into the phospholipid bilayer to aid in different functions. Match each molecule to the function it provides. Phosphate

Structure

_____ change their activity in order to bring the body back to its normal state.

Targets

Which of the following is not a factor that determines whether or not a molecule is allowed to cross a cell membrane?

Temperature

Which of the following statements best describes the function of a cell membrane?

The cell membrane has many functions, but its primary action is to regulate the movement of materials into and out of the cell.

Why do the blood vessels going to the skin and internal digestive organs constrict and get smaller during a fight-or-flight response?

To redirect blood to the areas that are involved in the panic response

Different molecules are mixed into the phospholipid bilayer to aid in different functions. Match each molecule to the function it provides. Protein

Transport

Which organelle is involved in the storing of water in plant cells?

Vacuole

If you place a plant cell in a solution that has a higher salt concentration, which of the following will occur?

Water exits the cell The cell shrinks water enters the outside solution

Which of the following is an internal stimulus?

When an animal is in pain

Your hand gets too close to the campfire while you are roasting marshmallows. What would happen if your body's sensors are not working?

You would burn your hand

Physical reaction is part of an interesting human response called "fight or flight." Which of the following is not a physical reaction that you may have when your body is entering the fight-or-flight response?

Your mouth waters

Match each organelle to its corresponding description. allows materials in or out of the cell

cell membrane

Which of the following does not affect a molecule's ability to cross a cell membrane?

energy of the cell

Match the stimulus to an animal's corresponding response. When an animal notices a change in seasons such as summer.

migration

Match each organelle to its corresponding description. forms around materials, and exports out of the cell

vesicle

Diffusion is a type of passive transport. Which of the following are also considered characteristics of diffusion?

works from a region of higher concentration to one of lower concentration does not require energy helps oxygen cross the cell membrane easily