NUTRIENT BIOCHEMISTRY: PART 2

Use the Nelson text, "Biology 11", pp. 37-39 to complete the blanks.


* LIPIDS *

Lipids taste __________________ but are also the cause of serious ________________ such as _________________ _______________ disease and __________________.

Lipids are divided into _______________ groups: (a) ______________, ________________, and ________________; (b) ___________________, and (c) __________________.

Like _____________________, lipids supply ______________ to cells but they are ______________________ for the body to break down so you usually feel _______________________ longer after eating lipids than after eating carbohydrates and __________________.

Lipids are an excellent ________________ storage compound. One __________ of lipid contains approximately _______________ as much energy as one gram of __________________ or __________________. Lipids aid in absorption of __________________, serve as ____________________ for the body, are key components of cell _______________________, protect some of the delicate ________________ of the body, and act as raw materials for the synthesis of ___________________, etc.

Lipids contain _________________, hydrogen, and _________________ but in different proportions from _____________________. Lipids are ______________________ in water. This is why lipids ___________________ on the surface of water. The most common type of lipid is composed of 2 structural units: one __________________ molecule and three _________________ ____________ which combine to form a ______________________. (Because water is being removed in this chemical reaction, it is called a ________________ ____________________).

Draw Fig. 1 on pg. 38 which shows the synthesis of a triglyceride (chemicals in coloured boxes only)



















Glycogen supplies are limited in animals and if glycogen supplies are full, excess ________________________ are converted into __________.

If a _______________ acid contains only ________________ bonds between carbon atoms, then the fatty acid is described as _________________. They contain the maximum number of ___________________ atoms possible. If some of the _________________ atoms are missing, that is, if there are ___________________ bonds between some of the carbon atoms, the fatty acid is said to be _______________________.

Draw Fig. 1 on pg. 38 (saturated and unsaturated fatty acid)















Liquid fats are often referred to as ______________ such as __________________ seed oil and ___________ oil. Plant fats are often described as __________________________ since their fatty acids contain many __________________ ________________. Animal fats have the maximum number of ___________________ atoms and are __________________. The greater the number of ________________ atoms, the _____________________ the fat. _______________ and __________________ are examples of saturated animal fats. Sometimes hydrogen atoms are added to the _______________________ plant fats to make them _________________ through a process called ____________________________. __________________________ is an example of a plant fat or oil that is hydrogenated. Since _________________________ fats are harder for the body to break down (and they are more solid), they can be harmful for the body (and can cause clogged arteries).

A second group of lipids is called __________________________. They differ from _________________________ in that one of the fatty acids attached to the ______________________ backbone of the molecule is replaced by a ______________________ group. This creates a _________________ end that is soluble in ________________, while the two fatty acids form a ____________________ end that is ___________________.

Draw Fig. 3 on pg. 39 (phospholipid structure)

















A third category of lipids includes cholesterol which serves many _________________ functions. It is one of the chemicals used to make certain _______________________. The male and female _________ _________________ are made from cholesterol. Cholesterol is also an important part of the ________ _____________________.

Certain forms of cholesteroll have been associated with ____________________ disease and ________________________ problems. If it combines with other ___________, it can form a _____________________ that may block _______________ _______________ (see Fig. 4, pg. 39).


3-D MOLECULES ACTIVITY: LIPIDS

  1. Construct models of a saturated and an unsaturated fatty acid.

  2. Working with another group, construct a model of a phospholipid molecule (ignore the + charge on the "N" and the - charge on the "O". Make each fatty acid with 4 "CH2" groups and 1 "CH3" in the tail).