Homeostasis EOC Review

Homeostasis and the Cell Membrane

EOC Review

Pre-Assessment

Multiple Choice

Organisms maintain a balance between their cells and the external environment through the process of -

• growth

• cellular respiration

• homeostasis

• pH

Multiple Choice

Some fish travel from saltwater to freshwater or from freshwater to saltwater but still maintain the concentration of salt in their cells. This is an example of -

• cellular injury

• homeostasis

• positive feedback

• mutation

Multiple Choice

You are growing a tomato plant in your house. Which of the following would the plant probably do to help maintain homeostasis?

• Grow away from the light coming from the window

• Grow toward the light coming from the window

• Growth is not affected by the light coming from the window

• Grow the leaves away from the light coming from the window but the flowers towards the window

Multiple Choice

Which structure, composed mainly of proteins and lipids, aids in maintaining homeostasis in a cell?

• chromosome

• centrosome

• cell membrane

• nucleolus

Multiple Choice

Which is an important function of the cell structure in this model?

• Packaging cell products for export

• Controlling passage of materials

• Preventing a cell from bursting due to osmosis

• Transferring hereditary material to offspring

Homeostasis is how living things remain balanced

• ALL living things maintain homeostasis

• It is the maintenance of a stable internal environment in response to changes

• In other words, without homeostasis you would die whenever your environment changed

Multiple Choice

The maintenance of an organism’s internal environment is called:

• compensating
• homeostasis
• balancing
• routine

Multiple Choice

Which kingdom of organisms is NOT capable of maintaining homeostasis?

• Protista

• Fungi

• Plantae

• All living things are capable of maintaining homeostasis

To maintain homeostasis, cells and organisms must respond to stimuli

• A stimulus (plural = stimuli) is any change in its internal or external environment

• External stimuli may include temperature, light, a predator, etc

• Internal stimuli may include pH, water level, oxygen level, disease, etc

Multiple Choice

Which term best describes a change in the external environment that initiates a response?

• Synapse

• Stimulus

• Receptor

• Regulator

Multiple Choice

A plant placed in a windowsill will turn its leaves towards the sun. This is an example of -

• reproduction

• responding to a stimulus

• metabolism

• development

The goal of homeostasis is to return the body to a balance

• Sweating maintains homeostasis by cooling your body in response to heat (the stimulus)

• Shivering maintains homeostasis by warming your body in response to cold (the stimulus)

Multiple Choice

Most animals do not sweat the way humans do when they are hot. Which of the following would NOT help an animal maintain homeostasis if it is overheated?

• Circulating blood to their ears and surface of their skin to allow heat to escape

• Panting to release hot air

• Standing in shallow water

• Basking in the sun on a warm rock

Multiple Choice

Exercise requires a lot of energy, and your body requires oxygen to use respiration and release more energy. Which of the following responses to exercise is helping you maintain homeostasis?

• Heavy breathing and increased heart rate

• Strengthening of your muscles

• Fatigue and light-headedness

• Increased body temperature

Your cells maintain homeostasis through their cell membranes

• ALL cells have a cell membrane

• Also called the plasma membrane or fluid mosaic model

• Determines what materials can enter and leave the cell

• It is selectively (semi) permeable - it lets some things through but not others!

Multiple Choice

Which cell structure is responsible for maintaining homeostasis by allowing materials in and out of the cell?

• Nucleus

• Ribosomes

• Cell Membrane

• Cell Wall

Multiple Choice

The plasma membrane is semipermeable. This means that -

• it allows anything in but not out of the cell

• it allows anything out but not into the cell

• it allows only certain things in or out of the cell

• it does not allow anything in or out of the cell

The cell membrane is like a chain-link fence

• Small materials can pass through the phospholipid bilayer (like the chain-link)

• Larger materials can only enter or leave through transport proteins (like the gates)

Multiple Choice

Which of the following is composed of two layers of phospholipids associated with proteins?

• Cell membrane

• Cell wall

• Cytoplasm

• Ribosomes

Multiple Choice

The diagram shows a section of a cell membrane that includes a channel protein (a type of transport protein). The function of this protein is to -

• connect reproductive cells during fertilization

• exchange organelles or chromosomes between specialized cells

• strengthen the outer boundary of the cell

• allow certain substances to enter or leave the cell

Post-Assessment

Multiple Choice

Homeostasis means -

• the equivalent of evolution

• the rate of metabolism

• the maintenance of a stable internal environment

• a gradual change over long periods of time

Multiple Choice

In order to maintain homeostasis, it is most important for an animal to be able to -

• change its habitat

• increase its prey population

• hide from its predators

• respond to its environment

Multiple Choice

Which of the following is an example of homeostasis maintenance?

• An animal feels hungry but refuses to eat for several days causing the animal to die of starvation

• Cancer cells become unstable when cell continue divide even after the are touching one another

• The roots of a plant do not grow deep enough into the soil to reach an adequate amount of water necessary for life

• A person experiences a rise in blood-glucose levels, which triggers the pancreas to produce more insulin to lever them

Multiple Choice

The function of the cell membrane is to -

• serve as a selective barrier between the inside the cell and the outside environment

• keep all external material outside the cell

• provide a waterproof barrier for the cell

• keep all materials inside the cell

Multiple Choice

The figure above shows the fluid-mosaic model of a cell's plasma membrane. Which of the following best describes the structure indicated by the arrow in the figure?

• A carbohydrate floating in phospholipids

• A transport lipid floating in phosphoproteins

• A transport protein floating in phospholipids

• A phospholipid floating in transport proteins