
Enzymes are proteins, which are large molecules that perform many jobs in your body. Enzymes are also catalysts, or substances, that speed up chemical reactions. A chemical reaction is a process in which one or more substances are transformed into one or more different substances.
Enzymes are important for our survival and are involved in many tasks that keep us healthy and active. For example, enzymes help you digest food, build muscles and protect your cells from damage.
E
nzymes interact with specific molecules called substrates. Every enzyme has an active site, which is where the chemical reaction takes place. These sites have unique shapes. Only one specific substrate can bind to an enzyme, just like only one key fits into a specific lock.
When the substrate binds to the enzyme, they form what is called the enzyme-substrate complex. Next, a chemical reaction takes place. When the reaction is complete, the enzyme releases the products of the reaction. A product is a substance that forms during a reaction. After the enzyme releases the products, it is ready to start all over again with another substrate molecule.
In your own words explain the difference between the two graphs below

What is the optimal pH for the green enzyme?
The diagram represents one way an enzyme can be inhibited.
Which statement explains the effect of an inhibitor on an enzyme?
Match the food to the chemical that it is tested with
| Stavka koja se može prevući | arrow_right_alt | Odgovarajuća stavka |
|---|---|---|
Glucose | arrow_right_alt | Iodine |
Protein | arrow_right_alt | Benedict's |
Lipids | arrow_right_alt | Biuret |
Starch | arrow_right_alt | Sudan III |
Mya eats pasta for lunch. Pasta is made of mostly starch molecules. For this to be useful to her cells, Mya's digestive system needs to break these starch molecules into:
Jack eats fish for dinner. Fish is high in protein molecules. After two hours, Jack's digestive system broke many of these proteins down into:
Chris eats a turkey sandwich. Starting at the mouth, what is the path that the molecules take through the body?
What are the tiny air sacs in the lungs called?
How does oxygen get into your body?
The chambers of the heart the receive blood from the body or lungs are the
The chambers of the heart that push blood out of the heart to either the body or the lungs are the
What side of the heart pumps oxygen poor blood?
What side of the heart pumps oxygen rich blood?
Blood flows from the Vena Cavas into the
Blood flows from the Lungs into the
Which statement correctly shows the path blood travels through the heart.
The Arteries ____________the heart , whereas the veins _____________heart

The heart pumps blood through a network of tubes inside the body called blood vessels.
What side of the heart pumps oxygen poor blood?
What side of the heart pumps oxygen rich blood?
Blood flows from the Vena Cavas into the
The upper chambers of the heart are the
The lower chambers of the heart are the
The chambers of the heart the receive blood from the body or lungs are the
The chambers of the heart that push blood out of the heart to either the body or the lungs are the
What side of the heart pumps oxygen poor blood?
What side of the heart pumps oxygen rich blood?

Match the chamber with the correct description
Pumps oxygen poor blood to the lungs
Receives oxygen poor blood from the body
Right Atrium
Right Ventricle
Match the chamber with the correct description
Receives oxygen rich blood from the lungs
Pumps oxygen rich blood to the aorta
Left Atrium
Left Ventricle
Match the Vena Cava with the correct description
Brings oxygen poor blood from the lower body (legs and feet) to the heart
Bring oxygen poor blood from the head and upper body to the heart
Superior Vena Cava
Inferior Vena Cava
Match the structure with the correct description
Wall like structure that prevents oxygen rich and poor blood from mixing
Preven blood from flowing backwards. Found between the atria and ventricles
AV valve
Septum
Blood flows from the Right Atrium into the
Blood flows from the Right Ventricle into the
Blood flows from the Lungs into the
Blood flows from the Left Atrium into the
Blood flows from the Left Ventricle into the
Oxygen rich blood is pumped out of the heart to the rest of the body by the
Which statement correctly shows the path blood travels through the heart.


Gas Exchange in Different Organisms
All living organisms need a way to exchange gases with their environment. This process is essential for respiration, which provides energy for life processes. Different organisms have evolved different gas exchange systems, but they all share common features to allow efficient diffusion of gases such as oxygen and carbon dioxide.
Common Features of Gas Exchange Systems
Although these gas exchange systems are found in different organisms, they share important similarities:
Large Surface Area – This increases the amount of gas that can diffuse at one time.
Thin Surfaces – A short diffusion distance allows gases to move quickly.
Steep Concentration Gradient – Maintained by blood flow in animals or air circulation in plants, ensuring efficient diffusion.
Gas Exchange in Humans
Humans and other mammals have lungs, which contain millions of tiny air sacs called alveoli. These alveoli provide a large surface area for gas exchange. Oxygen from the air we breathe in diffuses across the thin walls of the alveoli into the blood, while carbon dioxide diffuses out of the blood into the alveoli to be exhaled. The alveoli have very thin walls, only one cell thick, ensuring a short diffusion path for gases to move quickly between the lungs and the blood. Additionally, they are surrounded by a dense network of capillaries, which maintain a steep concentration gradient by constantly bringing in blood with low oxygen levels and removing oxygenated blood.
Gas Exchange in Fish
Fish live in water and rely on gills for gas exchange. Gills are made up of many thin filaments covered in tiny structures called lamellae, which increase the surface area for diffusion. Water containing oxygen flows over the gills, and oxygen diffuses into the blood in the gill capillaries. At the same time, carbon dioxide diffuses out of the blood and into the water. Fish use a counter-current flow system, where water and blood flow in opposite directions, maintaining a high concentration gradient for efficient gas exchange. Like alveoli, gills have very thin surfaces to allow gases to diffuse quickly.
Gas Exchange in Plants
Plants also need to exchange gases, particularly for photosynthesis and respiration. They do this through tiny openings on the underside of leaves called stomata. During the day, carbon dioxide from the air diffuses into the leaf through the stomata and is used in photosynthesis to produce oxygen and glucose. Oxygen then diffuses out of the leaf into the air. Inside the leaf, spongy mesophyll cells have air spaces that increase the surface area for gas exchange. Like other gas exchange surfaces, these cells have thin walls to ensure a short diffusion distance.
Why do living organisms need gas exchange?
What are the two main gases involved in gas exchange?
What is the main organ used for gas exchange in humans?
What are the tiny air sacs in the lungs called?
What is the function of alveoli?
Why are alveoli walls thin?
How does blood help in gas exchange in alveoli?
Where does gas exchange occur in fish?
What are the thin structures in fish gills called?
How does oxygen enter the fish’s blood?
What structures in leaves allow gas exchange?
Which gas enters a leaf for photosynthesis?
Where are stomata mostly found?
Why do gas exchange surfaces have a large surface area?
Why do gas exchange surfaces need to be thin?
What helps maintain a steep concentration gradient in gas exchange?
Name the four components of blood:
Check all the functions of blood
The clear liquid in which the cells are suspended in is
Which part of blood transports oxygen?
Which part of blood helps with blood clotting?
Which part of blood fights infections?
Move the description/function to the correct component of blood.
helps with blood clotting
lacks a nucleus
contains hemoglobin
helps fight infections
clear, yellowish fluid
transports oxygen
Red blood cell
White blood cell
Plasma
Platelet
Blood is responsible for transporting oxygen and nutrients throughout the body.
4. Blood…
What can be used to treat people with coronary heart disease?
Tick two boxes. |
Figure 3 shows the percentages of adults in the UK who have coronary heart disease.
Figure 3
Calculate the difference in the percentage of male and female adults aged 65 and over who have coronary heart disease.
Which is the correct conclusion for the data in Figure 3 (above)?
Tick one box. |
Suggest two risk factors for coronary heart disease.

Label Part A
Label Part B
Label Part C
Label Part D & F (the name they share)
Label Part G
Label Part H
Openings that allow for gas exchange are called
What two layers of the plant contain chloroplasts?
What is the primary function of the leaf? (One word)

What is part 6?
Label the tissue marked 2
By which process does carbon dioxide enter a plant?
The diagram below shows the surface of a leaf. Name part 2.

Why do leaves have a flattened shape? Choose the number of the best answer shown below.

How many different types of transport tissue do plants contain?
The equipment shown below was used to track the amount of water moving through a plant. The air bubble moves more quickly when water is lost from the leaves at a faster rate. Will the air bubble move faster or slower if the temperature is decreased?

Grade 9 question: A scientist carried out the experiment described below. Which type of transport tissue was the scientist trying to locate?

Which part of a plant is responsible for absorbing most of the water the plant needs?
Name one of the tissues that is found in the veins of plants.
Which environmental change would cause an increase in the rate of transpiration?
Tick (✓) one box.
Which factor could cause species A to have a higher rate of transpiration than species B?
Tick (✓) one box.
Identify the parts of the enzyme-substrate complex.
Identify the parts of the enzyme-substrate complex.
Identify the parts of the enzyme-substrate complex.
Identify the parts of the enzyme-substrate complex.
Blue enzyme would function in a environment with pH of 5
What is the function of the right atrium?
What is the function of the right ventricle?
What is the function of the left atrium?
What is the function of the left ventricle?
What is the function of the vena cavas?
What is the function of the aorta?
What side of the heart carries oxygen rich blood?
What side of the heart carries oxygen poor blood?
Identify structure on the heart.
Identify structure on the heart.
Identify structure on the heart.
Identify structure on the heart.
Identify structure on the heart.
Identify structure on the heart.
Identify structure on the heart.
Identify structure on the heart.
More or Less
More or Less
More or Less
Move up and out or Down and in
Breathing or Respiration
When needed, cells go through programmed cell death to make room for new cells
Usually the body would destroy a damaged cell that was not able to function
A tumor is benign if
Tumors that invade other tissues and spread through the body are known as
Malignant tumors are considered cancerous
Cancer makes people feel sick when the cancer cells disrupt the normal function of the body.
When is a tumor cancer?
When is a tumor not cancerous?
There is only one type of cancer
Cancer is......
Which of the following is NOT a factor that increase risk of cancer?
What two important activities are cells doing during interphase?
About how much time does a cell spend in mitosis?
Do nerve cells or follicle cells undergo mitosis more?
Checkpoint in the cell cycle are making sure the cell is dividing and replicating correctly
What is the process in which cells kill themselves?
Cancer cells are your body's own cells that are growing out of control
What are a group of cancer cells called
Name a side effect of chemotherapy.
Cancers cells can secrete their own growth hormones.
Cancer cells ignore checkpoint signals
Run English Ivy with no appliance. What is the result?
Run English Ivy with heater. What is the result?
Run English Ivy with fan. What is the result?
Run English Ivy with lamp. What is the result?
Fill out the table. Which factor has the highest rate of transpiration?
What is the name of the device the plant is in?
What is the independent variable through the row?
What is the dependent variable through the row?
Which species has the highest rate of transpiration and why do you think so?
What is transpiration?
Where do plants get their water?
Where do plants lose their water?