midterm

Question 1

*what makes the carbon different from other molecules?


Answer 1

it can form up to 4 bonds


Question 2

*which elements can it form the bonds with?


Answer 2

mostly carbon ( most stable), hydrogen, nitrogen and oxygen but also phosphorus and sulfur


Question 3

.what are functional groups?


Answer 3

is a specific combination of bonded atoms that always has the same chemical properties and therefore always reacts in the same way, regardeless of tthe carbon skelteon to which it’s attachted to.


Question 4

*true or false: carbon is the skeleton/ backbone of an organic molecule.


Answer 4

true

Question 5

What are the four biomolecules

Answer 5

Carbs, lipids, proteins and nuevlic acids


Question 6

Why are lipids not polymers?


Answer 6

Because they contain two different subunits, glycerol & fatty acids


Question 7

Enzymes

Answer 7

: A) not consumed in reaction , B) not changed by the reaction, C) catalysts.


Question 8

Carbs are in a ———- ratio


Answer 8

1:2:1

Question 9

list hexoses and pentoses

Answer 9

glucose ( blood sugar), fructose(fruit sugar) and glactose (sugar in diary) are the hexoses monosaccharides for carbs./ ribose and dexyribose( sugars in dna) = pentoses.


Question 10

what is the function of cellulose

Answer 10

Cellulose fibrils are in a criss- cross formation in plants for extra strength and rigidity.


Question 11

differentiate saturated and unsaturated

Answer 11

saturated: single bonds only, solid at room temperature
unsaturated: one or more double bonds, liquid at room temperature

Question 12

Why do unsaturated fats melt faster

Answer 12

The reason is that a double bond creates a KINK in the fatty acid chain that prevents close parking between the hydrocarbon chain.


Question 13

what is cholesterol

Answer 13

. Cholesterol is an essential component of an animal cell’s plasma membrane, where it provides physical stability. *Cholesterol is the precursor of several other steroids, such as the sex hormones testosterone and estrogen


Question 14

what are steroids

Answer 14

Four fused carbon rings


Question 15

what kind of bond is peptide

Answer 15

covalent

Question 16

structure of amino acid

Answer 16

R
        |
H3N+ - C - COO- 
         |
        H

Question 17

what is the central C in amino acid structure called

Answer 17

alpha carbon

Question 18

in a dipeptide bond, how many bonds are there?

Answer 18

One bond and 2 amino acids


Question 19

Which amino acids contain sulfur?


Answer 19

Cysteine and Methionine


Question 20

True/ false: The denaturing causes the break of a peptide bond


Answer 20

false

Question 21

what are the 9 essential amino acids

Answer 21

Essential amino acids cannot be made by the body. As a result, they must come from food.
The 9 essential amino acids are histidine, isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan, and valine.

Question 22

what are prions

Answer 22

a type of protein that can trigger normal proteins in the brain to fold abnormally.

Question 23

what are the functions of proteins

Answer 23

1- metabolism
2-support
3-transport
4-defense
5-regulation
6-motion
7-nutrient and storage

Question 24

what is TSEs

Answer 24

Fatal brain diseases ;Transmissible spongiform encephalopathi

Question 25

what is DNA

Answer 25

Genetic material that stores information for its own replication and for the sequence of amino acids in proteins


Question 26

what are purines

Answer 26

Adenine & guanine


Question 27

what are pyrimidines?


Answer 27

Thymine in DNA, uracil in RNA and cytosine.


Question 28

What is a nucleosome

Answer 28

a structural unit of a eukaryotic chromosome, consisting of a length of DNA coiled around a core of histones.


Question 29

what is the backbone of nucleic acid composed of

Answer 29

The backbone of the nucleic acid strand is composed of alternating sugar-phosphate molecules.


Question 30

T or F: .”The number of A + G (purines) always equals the number of T + C (pyrimidines).


Answer 30

true

Question 31

what is central dogma

Answer 31

genetic information flows only in one direction, from DNA, to RNA, to protein, or RNA directly to protein.

Question 32

One if the main differences between DNA and RNA:


Answer 32

Carbon molecule in the pentose sugar base, 2nd one, in rna its bonded to OH and in DNA its bonded to H


Question 33

how many bonds between A&T and G&C

Answer 33

Double bond between A& T, triple bond between G& C


Question 34

what is ATP

Answer 34

Adenosine triphosphate (ATP) is the source of energy for use and storage at the cellular level. The structure of ATP is a nucleoside triphosphate, consisting of a nitrogenous base (adenine), a ribose sugar, and three serially bonded phosphate groups.

Question 35

what is a chromatosome

Answer 35

A nucleosome plus the h1 histone

Question 36

when is a polypeptide a protein

Answer 36

when its folded

Question 37

what is the difference between glycogen and insulin

Answer 37

In the liver, the insulin allows for glucose to be made into glycogen. Glycogen is stored glucose that is broken down when the body needs energy. Insulin also prevents the production of glucose from other nutrients.

Question 38

LDL Vs. HDL

Answer 38

high-density lipoproteins are better than low-density lipoproteins

Question 39

what is the function of micelles

Answer 39

They help the small intestine to absorb essential lipids and vitamins from the liver and gall bladder. They also carry complex lipids such as lecithin and lipid soluble vitamins (A, D, E and K) to the small intestine.

Question 40

what is chylomicron

Answer 40

are lipoprotein particles that consist of triglycerides, phospholipids, cholesterol, and proteins. They transport dietary lipids from the intestines to other locations in the body.

Question 41

what is hydrogenation

Answer 41

saturating some double bonds and converting others to trans configuration in order to provide a firm firmness and plasticity to shortenings, thereby, enabling the production of solid and semi-solid fats.