Docsity
Docsity

Prepare for your exams
Prepare for your exams

Study with the several resources on Docsity


Earn points to download
Earn points to download

Earn points by helping other students or get them with a premium plan


Guidelines and tips
Guidelines and tips

Understanding Digestion: Mechanical and Chemical Processes, Schemes and Mind Maps of Human Biology

An overview of the digestive system, explaining how it breaks down food into nutrients that can be used by the body. It covers both mechanical and chemical digestion, the role of various organs, and the importance of enzymes. Students will learn about the process of digestion from the mouth to the large intestine.

Typology: Schemes and Mind Maps

2021/2022

Uploaded on 09/27/2022

prindhorn
prindhorn 🇺🇸

4.6

(11)

279 documents

1 / 5

Toggle sidebar

This page cannot be seen from the preview

Don't miss anything!

bg1
1!.....'--.:s
:',i,r
ll!.
::,\
i::a;
..!ii.i:i. ---*i,,,.,., r*
,,.rj .'11 # lij
d5, r
.,,.-!n1 ,,gl i:
..! 4;: $*1
i"+ .$ ii:;
:-: '-'l-. -;..- . . -1
t"
k' Ifl-:t'ff'E:1'rl I-.-Y:
ldentify As you read, undertine
the ways that your body uses
n utrients.
*
T
;1
:
:
-
B
kr
The Stomach
6 lnfer The stomach tining is made up of deep muscutar
grooves. How do you thinl< these structures help the
stomach to breal< down food?
Sa
SA
ln t-
grir
ln th
are I
ffiFrcm$" $s &fu* #$gms€Erus*= sgss€+=rceH
Your cells need a lot of energy for their daily activities. Cells
use nutrients, which are substances in food, for energy, growth,
maintenance, and repair. The digestive system breaks down the food
you eat into nutrients that can be used as building materials and
that can provide energy for cells.
The digestive system interacts rvith other body systems to
obtain and use energy from food. Blood, part of the circulatory
system, transports nutrients to other tissues. In order to extract
energy from nutrients, cells need oxygen. The respiratory system
is responsible for obtaining this oxygen from the environment.
The nerr.ous system controls and regulates the functioning of the
digestive system.
W$#mH #Fj*ffi €"fu* E+-s+ Epsg"Btrs #,$ €€$g*sE:E+src.i-
Digestion is the process of breaking down food into a form that
can pass from the digestive system into the bloodstream. There are
two types of digestion: mechanical and chemical.
48 Unit l Human Body Systems
-T
pf3
pf4
pf5

Partial preview of the text

Download Understanding Digestion: Mechanical and Chemical Processes and more Schemes and Mind Maps Human Biology in PDF only on Docsity!

1!.....'--.:s :',i,r ll!. ::,\ i::a;

,,.rj^ ..!ii.i:i. .'11^ ---i,,,.,.,^ r

d5, lijr

..! .,,.-!n14;: ,,gl$*1^ i: i"+ .$ :-: '-'l-.^ ii:;-;..-.. (^) - t" k' (^) Ifl-:t'ff'E:1'rl I-.-Y: ldentify As^ you^ read, undertine the ways that your^ body uses n utrients.

T ; : :

B kr

The Stomach

6 lnfer The stomach tining is made up of deep muscutar

grooves. (^) How do you (^) thinl< these structures help the stomach to breal< down food? Sa SA ln (^) t- grir ln th are I ffiFrcm$" $s (^) &fu* #$gms€Erus*= sgss€+=rceH Your cells need a lot of energy for their daily activities. Cells

use nutrients, which are substances in^ food,^ for^ energy,^ growth,

maintenance, and repair.^ The^ digestive system^ breaks^ down the food

you eat into nutrients that can be used as building materials^ and

that can provide^ energy^ for^ cells. The digestive system interacts rvith other body^ systems^ to obtain and use^ energy^ from^ food. Blood,^ part^ of the^ circulatory

system, transports nutrients to other tissues. In order to extract

energy from nutrients,^ cells need oxygen.^ The respiratory^ system is responsible for obtaining this oxygen from the environment. The nerr.ous system^ controls^ and regulates^ the^ functioning^ of the digestive system. W$#mH #Fjffi €"fu E+-s+^ Epsg"Btrs #,$^ €€$g*sE:E+src.i- Digestion is the process of breaking down^ food into^ a^ form that can pass from the digestive system into the bloodstream. There are two types of digestion: mechanical and chemical. 48 Unit^ l^ Human Body Systems -T

.lechanical digestion is the breaking, crushing, and mashing of

-.od. Chewing^ is^ a type of mechanical digestion. Chewing creates .nrall pieces (^) of food that are easier to (^) swallow and digest than large :Leces are. Mechanical digestion increases the surface (^) area of food

. (^) .,r the action of chemical digestion.

-hernical digestion^ is^ the^ process^ in which^ large^ molecules^ of

,-,od are broken down into smaller molecules so that they can pass

.rto the bloodstream. An enzyme (EN.zym) is a chemical that the

-.odr. uses^ to break down^ large^ molecules into smaller molecules. -nzymes (^) act like (^) chemical scissors. They'tut (^) up" large molecules .nto smaller pieces. Mechanical digestion breaks up food (^) and -ncreases surface area so that enzymes can (^) break nutrients into

.r-naller molecules. Without mechanical digestion, chemical

Jigestion (^) would take days instead of hours!

7 Categorize Decide whether (^) each of these steps in (^) digestion is an example of mechanicat (^) digestion or chemical digestion. (^) Then put (^) a checl< in (^) the correct box.

In your mouth, teeth grind food. ffmechanicat

t chemical

Salivary glands^ release a tiquid called saliva, which helps to break food down.

! mechanicat

ffchemicat ln the stomach, (^) muscles contract to grind food into (^) a pulpy mixture.

Mmechanicat

n chemicat

In (^) the smal[ intestine, most nutrients are broken down (^) by enzymes.

f mechanicat

AU l:l/chemicat

{

,il

I",|I lnl^ :

i, 'l:!. r,l'^ .e

t .# Lesson 4 The Digestive and Excretory S@'ems (^49)

The stomach is a muscular bag that crushes food and contains acids

and enzymes for^ killing^ bacteria^ and^ breaking down proteins. The

walls of the stomach contain layers of muscle so the stomach walls

can churn and mix food. This is the final^ step^ in^ the process^ of

mechanical digestion of the food you^ have eaten. Tiny glands in the stomach release^ a^ special^ type of^ acid^ that

is so harsh that it kills most bacteria that might be swallowed with

your food. A coating of thick mucus protects the^ stomach^ lining

from the acid. The glands in the stomach also release enzymes that begin the process of breaking down proteins. The^ enzymes^ that

break down proteins^ can^ function only in^ the acidic^ environment^ of

the stomach.

After a few^ hours^ in^ the^ stomach,^ food^ is

reduced to a soupy mixture called chyme (kym). (^) Chyme leaves the stomach and moves into the small intestine. The smatl intestine is^ a muscular tube where most chemical digestion takes place and most nutrients are absorbed.

After food moves^ through^ the

small intestine, it moves to the large intestine. In^ the^ large intestine, water and nutrients are absorbed. Most of the solid material remaining is waste, which is compacted and stored.

Eventually it is eliminated from

the body.

Leqson 4 The Digestive and Excretory Systems 51

ffi

l

,I ;i.. ':lill ,iiril

l$ il

,it t I fl 1t ll

=#r*'

kEes =F* (^) ==€=E**Es

.wsrfu*#E

The digestion of nutrients in^ the small intestine^ takes place^ with

the help of three organs that attach to the small intestine. These organs are the pancreas,liver,^ and gall bladder. The pancreas (PANG.kree.uhz)^ makes fluids that break down

eyery type of material found in foods: proteins, carbohydrates, fats,

and nucleic acids. The tiver makes and releases a mixture called bile that is then stored in the gail bladder. Bile breaks up iarge fat droplets into very small fat droplets.

i :=i (^) l, J-r :,11^ :i^ 1.,,.1a :'^ i^ :i:'::i,aiir;.i^ I,i i:'.ii'ir:,:

After nutrients are broken down, they are absorbed into the bloodstream and used by the body's cells. The inside wall of the small intestine

has three features that allorv it to absorb nutrients

efficiently: folds, villi, and microvilli.

First, the walls of the small intestine have many folds. These folds increase the surface area inside the intestine wall, creating more room for nutrients to be absorbed. Each fold is

covered with tiny fingerlike projections called

villi (YIL.eye). In turn, the villi are covered with

projections called microvilli. Microvilli increase

the surface area of the villi. Villi contain blood

and lymph vessels that absorb nutrients from

food (^) as it passes (^) through the small intestine.

T'he large intestine removes water from mostly- digested food,^ absorbs vitamins,^ and^ turns food

waste into semi-solid waste called feces.

Some parts of food,^ such as the^ cell^ walls^ of

plants, cannot be absorbed by the body. Bacteria live in the large intestine that feed off of this undigested food. The bacteria produce vitamins that are absorbed by the large intestine along

with most of the water in the undigested food.

The rectum is the last part of the large

intestine. The rectum stores feces until it can

be expelled. Feces pass to the outside of the body through an opening called the anus.It

takes about 24 hours for a meal to make the full

journey through a person's digestive system.

inlil

10 Relate How is the structure and function of this sponge similar to that of the smatt intestine? *rt r *-l :lc

;"rj __a .: iId

Small intestine

q

This (^) natvral sTonge has many c?evattet,which incrLase its (^) sur{ace area.

ffi.^ e# ;#r:' Vlli^ eoverthe sur{ace o{ the^ small inferline.