bio12

Question 1

1

what do we mean when we say scientific method? what is the importance of the scientific method?

Answer 1

we ask question, onserve the world, formulate hypothesis, test them in controlled experiments, revise, and make conclusions.

Question 2

what is the difference between a hypothesis and a theory? give 2 exaple?

Answer 2

Hypothesis is that we can prove with experiment. ex: growing plants, what colour butterfly like the most.
theory is that we cant prove by experiment ex: bing bang, here does first atome came from.

Question 3

what is a control? give an exaple. explain the role of control in an experiment?

Answer 3

A control group is a sample that undergoes all the same steps in the experiment except the one beig tested. THE Control group is neccessary so that scientists may establism a cause and effect relitionship of indipendent variable specifically.

Question 4

Define homeostasis and describe at least three example?

Answer 4

Homeostasis is the way the body keeps things balanced and stable, like keeping the right temperature, the right amount of water, and the right sugar level in the blood.

Question 5

what is meant by negative feedback in biological systems? give examples of homeostatic control through negative feedback in human system?

Answer 5

Negative feedback is when the body notices a charge and tries to fix it to stay balanced. for ex. if you get too hot, you sweat to cool down.

Question 6

what is meant by positive feedback in biological systems? give examples of homeostatic control through positive feedback in human system?

Answer 6

Positive feedback happens when the body pushes a change to keep getting stronger. for ex: during childbirth and contractions get stronger to help reliver the baby.

Question 7

what characteristic of the water molecule gives water with so many qualities essential to life?

Answer 7

Water has a special shape with one oxygen and two hydrogen atoms, making it act like a tiny magnet, which helps it stick to things, dissolve substances, and support life.

Question 8

why is water considered to be polar molecule? show a diagram to use in your explanation.

Answer 8

Water is a polar molecule because oxygen pulls electrons closer, making one side slightly negative and the other side slightly positive, like a tiny magnet.

Question 9

what is an acid? give two examples. what pH’ do acids have?

Answer 9

An acid is a substance that tastes sour, can react with metals, and has a pH below 7, like lemon juice (pH 2) and vinegar (pH 3).

Question 10

what is an base? give two examples. what pH’ do acids have?

Answer 10

A base is a substance that feels slippery, tastes bitter, and has a pH above 7, like soap (pH 9) and baking soda (pH 8).

Question 11

is pure water an acid or a base? explain.

Answer 11

Pure water is neither an acid nor a base because it has a pH of 7, which is neutral, meaning it is perfectly balanced between acidic and basic.

Question 12

some acid rain has pH of 2. how much more acidic is this than natural rainwater pH6.

Answer 12

Acid rain with pH 2 is 10,000 times more acidic than natural rainwater with pH 6 because each drop in pH is 10 times more acidic.

Question 13

why is the maintenance of pH crucial to biological systems?

Answer 13

Keeping the right pH in living things is important because enzymes and cells only work properly at certain pH levels, and big changes can harm or even kill them.

Question 14

what is a buffer? why are buffers significant to biological system?

Answer 14

A buffer is a substance that helps keep pH steady by balancing acids and bases, which is important in living things to keep cells and enzymes working properly.

Question 15

what is a polymer? give 4 examples of polymers.

Answer 15

A polymer is a large molecule made of many smaller repeating parts, and examples include DNA, proteins, plastic, and starch.

Question 16

list the major funtions of protiens?

Answer 16

Building and fixing body parts
Helping speed up body reactions
Carrying oxygen
Protecting the body from sickness
Sending messages in the body
Giving support to cells

Question 17

which elements are found in proteins? which one is most characteristic of proteins?

Answer 17

Proteins are made of carbon, hydrogen, oxygen, nitrogen, and sometimes sulfur, with nitrogen being the most important element that makes proteins unique.

Question 18

what are the building blocks (monomers) of proteins?

Answer 18

The building blocks of proteins are amino acids, which link together to form proteins.

Question 19

“a generalized formula for an amino acid and label the groups. How many amino acids are found in nature? In what way do these amino acids differ from each other?”

Answer 19

An amino acid has a general formula: a central carbon (C) bonded to an amino group (-NH₂), a carboxyl group (-COOH), a hydrogen (H), and a side chain (R), which makes each of the 20 natural amino acids different from one another.

Question 20

Dehydration Synthesis

Answer 20

When two amino acids join, dehydration synthesis removes a water molecule (H₂O) to form a strong bond, while hydrolysis adds water to break the bond and separate them.

Question 21

Hydration (Hydrolysis) –

Answer 21

when a protein is broken down, a water molecule is added, breaking the peptide bond and separating the amino acids.

Question 22

What do we call the type of bond that forms between amino acids?

Answer 22

peptide bond

Question 23

What is the difference between a polypeptide

Answer 23

A polypeptide is a long chain of amino acids linked by peptide bonds, but it may not be fully functional.

Question 24

What is the difference between a protein?

Answer 24

A protein is a polypeptide (or multiple polypeptides) that has folded into a specific shape and can perform a function in the body.

Question 25

Describe the four levels of organization and protein.

Answer 25

1) Primary structure – A simple chain of amino acids in a specific order. 2) Secondary structure – The chain folds into shapes like alpha helices or beta sheets, held by hydrogen bonds. 3) Tertiary structure – The protein folds further into a 3D shape due to interactions between side chains (R groups). 4) Quaternary structure – Two or more polypeptides join together to form a complete, functional protein.

Question 26

What determines the function of a protein?

Answer 26

A protein's job depends on its shape, which comes from the order of its amino acids and how they fold.

Question 27

What happened to a protein that has become denatured using example 3 signals that cause a protein to become denatured?

Answer 27

When a protein becomes denatured, it loses its shape and can’t work properly. For example, if you cook an egg, the heat changes the egg white from clear to solid because the proteins lose their shape. Three things that can cause denaturation are: Heat – Acid – Salt –

Question 28

Define Carbohydrate

Answer 28

A carbohydrate is a type of nutrient that gives your body energy. It is made of sugar molecules, and you can find it in foods like bread, rice, and fruits.

Question 29

The main functions of carbohydrates is a living organism?

Answer 29

Carbohydrates give energy, store energy, and help build parts of cells in living things.

Question 30

What is the formula for glucose? What is glucose used for?

Answer 30

The formula for glucose is C6H12O6. Glucose is used by the body for energy and is also stored in the form of glycogen for later use.

Question 31

Differentiate between monosaccharides, disaccharides, and polysaccharides and give example of each?

Answer 31

A monosaccharide is one sugar, like glucose. A disaccharide is two sugars joined, like sucrose (table sugar). A polysaccharide is many sugars linked, like starch in plants.

Question 32

how do disaccarides form from monosaccharides?

Answer 32

A disaccharide forms when two monosaccharides join, and a water molecule is removed.

Question 33

What are the major differences in structure and function among the common polysaccharides, glycogen, starch, and cellulose?

Answer 33

Glycogen (found in animals) and starch (found in plants) store energy, while cellulose (found in plants) gives structure; glycogen and starch are easy to break down, but cellulose is tough and hard to digest.

Question 34

In vertebrates' Like Humans, where do we find rich stores of glycogen?

Answer 34

In humans and other vertebrates, glycogen is mainly stored in the liver (for blood sugar control) and muscles (for quick energy during movement).