chapter 20: unifying concepts of animal structure and function

Chapter 20: Unifying Concepts of Animal Structure and FunctionNEW AIM: How are animals organized?

Fig. 20.1

Chapter 20: Unifying Concepts of Animal Structure and FunctionAIM: How are animals organized?

Tissue :

cooperative unit of many similar cells performing a special function

Fig. 20.2


Tissue :

4 major types in animals

Fig. 20.2


Tissue :

4 major types in animals1. Epithelial tissue

- covers and lines the body and its parts

Fig. 20.4


Tissue :

4 major types in animals1. Epithelial tissue

- covers and lines the body and its parts


Tissue :

4 major types in animals1. Epithelial tissue2. Connective tissue

- Cells are sparse and scattered through an ECM like raisons in bread- Cells produce ECM (raisons make the bread)

Fig. 20.5


Tissue :

4 major types in animals1. Epithelial tissue2. Connective tissue

- Cells are sparse and scattered through an ECM like raisons in bread- Cells produce ECM (raisons make the bread)


Tissue :

4 major types in animals1. Epithelial tissue2. Connective tissue3. Muscle tissue

- made up of muscle fibers (cells)- most abundant tissue type in animals

Fig. 20.6


Tissue :

4 major types in animals1. Epithelial tissue2. Connective tissue3. Muscle tissue

- made up of muscle fibers (cells)- most abundant tissue type in animals


Tissue :

4 major types in animals1. Epithelial tissue2. Connective tissue3. Muscle tissue4. Nervous tissue

- neuron = a single nerve cell (a single wire)- forms a rapid communication system- senses stimuli, processes and directs response

Fig. 20.7


Several tissues are organized to form an organ:

Fig. 20.8


Several tissues are organized to form an organ:

Chapter 20: Unifying Concepts of Animal Structure and FunctionAIM: How are animals organized?Organs cooperate to build organ systems:

Fig. 20.9Organ systems cooperate to complete the body…


Fig. 20.9

Function is to bring in chemicals (nutrients: monomers, fatty acids, glycerol, cholesterol, vitamins [used as coenzymes – organic cofactors], minerals [ions to be used as cofactors, neuron firing, etc…]) to your cells for building (biosynthesis), storing, or burning to generate ATP for building.


Fig. 20.9

Serves for gas exchange. Bring in molecular oxygen (O2) to your blood, which will be used to perform cell respiration by your cells. To get rid of (excrete) CO2 and H2O waste coming from cell respiration (CO2 released during grooming and Krebs, H2O formed at the end of the ETC from the reduction of O2).


Fig. 20.9

The heart pumps blood around your body in hollow tubes made of cell called arteries, veins, and capillaries (these would be the roadways of your body). EVERY cell is at most three cell lengths away from a capillary (from the blood supply). The system delivers nutrients and oxygen to all cells for building, burning or storing, and takes away the waste products that cells excrete like CO2 and urea (nitrogen waste from the deamination of amino acids). CO2 will be eliminated by the lungs (resp./excretory system) and the urea will be eliminated by the kidneys (excretory system). The blood also carries other substance like white blood cells (WBC’s).


Fig. 20.9

Cleans the blood of metabolic waste (waste from chemical reactions) like H2O from cell respiration, and urea from deamination. The kidney are “blood filters”, removing urea, excess salt or excess water and other undesirable chemicals from the blood. Although not shown, the respiratory system has excretory function in the elimination of CO2 since it is a gas along with the skin, which will release some urea, salt and water as sweat.


Fig. 20.9

Your cells must be able to talk to each other. For example, growth hormone coming from the pituitary gland in the brain instructs cells to undergo mitosis (bypass the G1 checkpoint) or insulin from the pancreas instructing the liver to take up glucose from the blood.

CELLS TALK…


Fig. 20.9

Your cells must be able to talk to each other. For example, growth hormone coming from the pituitary gland in the brain instructs cells to undergo mitosis (bypass the G1 checkpoint) or insulin from the pancreas instructing the liver to take up glucose from the blood.

The endocrine system uses hormones (chemicals: steroids, amino acids, polypeptides, proteins) put into the blood by endocrine cells, which bind to and signal others cells to perform certain functions. This system is typically slow and long term – takes a while for the hormones to circulate and they will stay around a while…


Fig. 20.9

The nervous system is also all about cellular communication, but instead of using chemicals released into the blood, it uses cells that act like wires called neurons that transmit electrical signals. These signals are extremely fast (up to 120 m/s) and are typically short lived. An example would be moving your finger or any other skeletal muscle. The electrical signal is sent from your brain, down your spinal cord and out to the muscle in your finger.


Fig. 20.9

There are millions upon millions of bacteria, fungi, parasitic worms, etc… that would love nothing than to take your organic molecules and make them lunch. Luckily you have an immune and lymphatic system. These systems work together to clear your body of foreign substance. White blood cells are responsible for the destruction of these substances. They, like all blood cells, are born in the bone marrow and serve to protect…


Fig. 20.9

What is life without a reproductive system? Nonexistent. This one if fairly self-explanatory.


Fig. 20.9

The muscular system is composed of all the skeletal muscles of the body. The skeletal muscles allow the body to move when combined with signals from the nervous system (and a lot of ATP of course)


Fig. 20.9

The skeletal system serves to support the body (without it you would be a blob on the floor), protects vital organs like your lungs, brain, spinal cord and heart, and contains marrow that produces blood cells.

The integumentary system is composed of the skin, hair and nails (feathers and scales), all of which are non-living. This system serves to waterproof, cushion and protect the deeper tissues, excrete wastes, regulate temperature, is the attachment site for sensory receptors to detect pain, sensation, pressure and temperature, and may attract a mate. In humans the integumentary system additionally provides vitamin D synthesis.

Integere means “to cover” (latin)


Fig. 20.9Organ systems cooperate to complete the body…

Chapter 21: Nutrition and Digestion

Nutrition and The Digestive System

NEW AIM: How do animals obtain nutrition?


1. Filter feeder 2. Substrate Feeder

3. Fluid Feeder 4. Bulk Feeder

Four Types of ANIMAL ingestion:

NEW AIM: How do animals obtain nutrition?


AIM: How do animals obtain nutrition?


macromolecules too large to cross plasma membraneanimals need monomers to make their polymers

REASONS:



What will the nutrients be used for?



(EGESTION)



Digestion must be contained in specialized compartments:

1. Digestion occurs in individual cells.

Single celled organisms:


A. Phagocytose and fuse lysosomes with the vesicle



Sponges

1. Digestion occurs in individual cells – can only eat detritus.

Phylum: Porifera




Fig. 21.3A

2. Gastrovascular cavity – allows organism to eat larger pieces of food- Digestion (gastro) and circulation (vascular) of nutrients to body; only one opening

Hydra:

Phylum: Cnidaria(Coelentrates)


- Cells lining GV cavity secrete hydrolytic enzyme onto the ingested food to chemically break it down (food its trapped in the cavity and circulated by flagella) and then phagocytose the remaining pieces to be further broken down by lysosomes.

Cnidocytes (stinger cells)- cell after which the phylum is named- found on surface of tentacles

Chironex fleckeri (“Box jellyfish”)

- each cell contains a coiled thread with a capsule (nematocyst)- when triggered, coil shoots out and wraps around/stings prey



Cnidarians

Platyhelminthes also uses a GV cavity




SYMMETRY


No symmetry Central axis where several cuts can be made through axis to make many equal pieces (like a pizza pie).

Only one plane can be cut to divide the organism into two equal halves.


- A tube beginning with the mouth and ending with the anus having specializations along the way for ingestion, digestion, absorption and egestion.


Fig. 21.3B

- All the remaining phyla (nematode to chordata) use an AC

3. Alimentary canal (AC)


1. Substrate feeders taking in soil through the mouth

Phylum: Annelida


Fig. 21.3B


2. Soil enters pharynx (throat) and then passes down the esophagus to the crop.3. The crop is an organ that moistens and stores food as the organism can eat soil quicker than it can digest and absorb the organic material.


Phylum: Annelida


Fig. 21.3B


4. The crop will slowly release food into the gizzard, which contains a bit of sand and serves to grind the food (mechanical digestion) like we do in out mouth to increase surface area for the upcoming chemical digestion.5. The pulverized material then enters the intestines where enzymes will be secreted into the canal to chemically breakdown the food (hydrolysis of polymers).


Phylum: Annelida


Fig. 21.3B


6. The intestines is also the site of absorption of monomers into the blood.

7. The undigested material is egested through the anus.


Phylum: Arthropoda

AIM: How do animals obtain nutrition?3. Alimentary canal (AC)

1. Similar to Annelids2. Bulk feeder, food ingested through mouth, passes down esophagus into a crop and then into a gizzard.3. The gizzard of insects can have hard teeth-like appendages for grinding the food.


Phylum: Arthropoda


4. Food then enters the stomach where enzymes are secreted by cells onto the food resulting in chemical digestion.

6. Gastric pouches are extensions of the stomach, increasing surface area to aid in absorption of nutrients into the haemolymph (“blood”).

5. The stomach is ALSO the site of absorption


Phylum: Arthropoda


7. The intestine is short and mainly used for water absorption.8. Undigested food is eliminated through the anus.


Phylum: Chordata


1. Bulk feeder, food ingested via mouth (still no teeth) and passes down esophagus into crop.2. Food is then slowly released into the stomach where some chemical digestion of proteins begin and a bit of mechanical digestion occurs. 3. Partially digested food then enters the gizzard to be mechanically digested.

Crop full with food


Phylum: Chordata


4. Many birds will eat stones, which will get caught in the gizzard and aid in the grinding of the food to increase the surface area.5. Food will then be passed back to the stomach for more mechanical digestion now the there is more surface area and then back to the gizzard. The food will go back a forth a number of times before moving into the small intestines.

Crop full with food


Phylum: Chordata


6. In the small intestines, the majority of the chemical digestion occurs followed by absorption of nutrients into the blood.7. Food then enters the large intestines where water and electrolytes (ions like Na+, K+, Cl-, Mg++, etc…).

Crop full with food

8. Undigested material is egested via anus.



Fig. 21.4

The Human Digestive System




1. The Mouth

Fig. 21.5a. Digestion Begins

i. Salivary Glands and saliva

- Slippery glycoprotein- Buffers- Antibacterial compounds (antibodies)

- 98% water

- Salivary amylase

ii. Chewing

- easier to swallow- increase surface area- Types of teeth

Mechanical Digestion

Chemical digestion

iii. Tongue- bolus


Uvula



Salivary amylase

Salivary amylase is an enzyme that catalyzes the hydrolysis of starch in the mouth.

Prefix (Amyl-) - StarchSuffix (-ase) - Enzyme



2. The Pharynx

Fig. 21.6

a. the swallowing reflex




2. The Pharynx

Fig. 21.6

a. the swallowing reflex- larynx moves up and epiglottis swings down to cover trachea- esophageal sphincter loosens up




3. The Esophagus

Fig. 21.7

a. peristalsis- circular muscle layer - contracts to push food down- longitudinal muscle layer - contracts to shorten esophagus- 5 to 6 seconds to get to stomach




4. The Stomach

Fig. 21.8

a. Holds 2 liters of food/drink (storage)b. Pinched off by sphincters on either end




Fig. 21.8

4. The Stomachc. Surface highly folded

(high surface area)




Fig. 21.8


i. tubular gastric glands- 3 cell types

1. Parietal cells

2. Chief cells


- Secrete HCl (hydrochloric acid) – pH of stomach is ~2 to 3, which will denature proteins and expose their peptide bonds to proteolytic (protein digesting) enzymes.

- Secretes the proenzyme (inactive) pepsinogen



Fig. 21.8



3. Mucous cells


- secrete mucus (slippery glycoproteins and other substances) to protect the stomach lining from the gastric juices.



Fig. 21.8



1. Mucous cells2. Parietal cells3. Chief cells

Secretions = gastric juice




Fig. 21.8

4. The Stomachd. Pepsinogen

1. Activated first by HCl (proteolysis) to become the active enzyme pepsin

(positive feedback)

2. Pepsin i protease

- enzyme that hydrolyzes proteinsii. Begins protein digestion in stomachiii. Further cleaves/activates pepsinogen

pepsinogen

HCl

pepsin

or pepsin




Fig. 21.8

4. The Stomache. Gastric glands OFF by default

1,2) See, smell, taste food sends nerve signal to initially activate glands3,4) Food in stomach activates cells to secrete hormone gastrin into blood

- gastrin binds to gland cells and keeps them active (increase HCl output)- high pH inhibits gastrin release (negative feedback)

5) Food is gone, glands are off


Small peptide



4. The Stomachf. Mechanical digestion

i. smooth muscle contracts to churnii acid chyme

- churned food + gastric juices- squirted into duodenum of small intestines- 2-6 hours to empty stomach




5. The Small Intestinesa. 6 meters long, 2.5 cm diameterb. Major site of chemical digestionc. Aided by Liver/Gall Bladder and Pancreas

i. Liveri. Produces bile






- contains bile salts

Taurocholic acidGlycocholic acid







Taurocholic acidGlycocholic acid- emulsifies fat





ii. Gallbladder- stores and concentrates bile (up to 60 ml)



- emulsifies fat

Fig. 21.10A





iii. Why is feces brown?- The brown color comes a combination of bile and a compound called bilirubin, which is a breakdown product of heme (the cofactor of hemoglobin).

Fig. 21.10A


bilirubin




iii. Why is feces brown?- The brown color comes a combination of bile and a compound called bilirubin, which is a breakdown product of heme (the cofactor of hemoglobin).


bilirubin

- Bilirubin is also the cause of yellowing around bruises and the yellowing in jaundice.

Jaundice - Look at the yellowing of the eyes…caused by too much bilirubin in the blood.




iii. Pancreasi. Produces digestive enzymes

-Trypsin

Fig. 21.10A

- Chymotrypsin

chymotrypsin






-Trypsin- Chymotrypsin

chymotrypsin


- Carboxypeptidase






- Pancreatic Lipase


- Carboxypeptidase






- Pancreatic Lipase- Pancreatic Amylase- Ribonuclease- DeoxyRibonuclease

- Carboxypeptidase





iv. Duodenum- first 25 cm of small intestines- acid chyme meets bile, pancreatic enzymes, enzymes from intestine wall (maltase, aminopeptidase, dipeptidase, sucrase, lactase) - all macromolecules digested





iv. Duodenum

Carbohydrates- pancreatic amylase, maltase- sucrase, lactase





iv. Duodenum

Proteins (proteases)- trypsin, chymotrypsin- aminopeptidase, carboxypeptidase- dipeptidase

(work together as a team)





iv. Duodenum

Nucleic acids (nucleases)- ribonuclease- deoxyribonuclease





iv. Duodenum

Fats- lipase with the help of bile salts


Mechanical digestion

Chemical digestion (hydrolysis)




iv. Duodenum





iv. The remainder of small intestines

Jejunum- Middle section of small intestines (2.5m long)


- Absorption of almost all nutrients (monomer, vitamins, minerals)





- Huge surface area 300m2 (tennis court) due to:

Fig. 21.10B

- folds and projections- villi- microvilli


Jejunum




iv. The remainder of small intestinesFig. 21.10B

- blood vessels and lymph vessels (lacteals) penetrate villi- Nutrients diffuse (facilitated if hydrophilic, simple if hydrophobic and small) or are actively transported into blood.

- Nutrients go first to liver, then heart and rest of body


JejunumWhere are all these nutrients going?

- Lipids will enter the lacteals, other nutrients enter blood





- Nutrients go first to liver (the gatekeeper), then heart and rest of body



- Liver removes many of the absorbed nutrientsA. Glucose and other monnosaccharides are removed and converted to glycogenB. Excess amino acids are removed and deaminated

- Amino group converted to urea and the rest can be burned or used for biosynthesis





- Nutrients go first to liver, then heart and rest of body



- Liver removes many of the absorbed nutrientsC. Many toxins are removed and converted to a non-toxic form like ethanol






ileum- Final section of small intestines





A. Absorb Vitamin B12 (cobalamin)


ileum- Final section of small intestines

Vitamin B12

B. Absorb bile salts



a. 1.5 meters long, 5 cm diameterb. Sphincter controls entrancec. Cecum/Appendixd. Function

- absorb water, salts and some vitamins- 7 liters enter alimentary canal/day

Fig. 21.11

- 90% absorbed by Small intestines- rest absorbed by large intestines

e. peristalsisf. Too little water absorbed = diarrheag. Too much water absorbed (peristalsis too slow) = constipation

h. Recum (store feces) / anus – double sphincter


6. The Large Intestines (cecum, colon and rectum)



Fig. 21.11

i. Bacteria in the colon (gut flora)

- Break down some of the fiber (cellulose) and release waste products that your cells can use…



- Produce vitamins like biotin (used by the “grooming” enzymes and vitamin K, which is needed for blood clotting.

- 99% are anaerobes- Make up 60% of the dry mass of feces- ~500 different species- One of the causes of flatulance



j. cecum



- The cecum of herbivores tends to much larger than that of carnivores

- Filled with bacteria to break down plant material.


ULCERS

How is the wall of the stomach protected from gastric juice?

Gastric Ulcers - occur when the mucous protection fails

Symptoms

- pain in upper abdomen several hours after eating



ULCERS



ULCERS



Symptoms


Helicobacter pylori


What would you hypothesize is the reason people get gastric ulcers?


ULCERS



Symptoms


Helicobacter pylori

- spiral bacterium- can survive low pH of stomach- attaches to lining and secretes neutralizing chemicals- mucous lining breaks down in region of infection- gastric juice now kills stomach cells quicker than mitosis can replace them


What would you hypothesize is the reason people get gastric ulcers?


VEGETARIANS

Can people get all the nutrients they need without eating animal products?

Essential amino acids - humans CAN’T make 8 of the 20 amino acids

Simplest way to get all the nutrients?

Eat meat and animal by-products - eggs, cheese and milk


- Complete proteins (have all amino acids)


VEGETARIANS

Can people get all the nutrients they need without eat animal products?

Essential amino acids - humans CAN’T make 8 of the 20 amino acids

Simplest way to get all the nutrients?

Eat meat and animal by-products - eggs, cheese and milk


- Complete proteins (have all amino acids)

Vegetarians MUST eat a variety of plant foods that collectively supply the essential amino acids

Ex. Beans + corn

- Incomplete proteins

Most plant proteins are deficient in one or more amino acids

Fig. 21.16


VITAMINS

- most are coenzymes


NAD+

MenB


VITAMINS

- most are coenzymes


- 13 vitamins are essential

Table - Page 445


MINERALS

- chemical elements other than C,H,O,N


- must be obtained in our diets

Table - Page 446


REVIEWI. Nutrition


- ingestion, digestion, absorption, egestion (elimination)- individual cells (porifera)- Gastrovascular cavity (Cnidarians)- Alimentary Canal (Arthropods, Annelids, Chordates)

Mouth -> pharynx -> esophagus -> crop, gizzard, stomach -> intestines -> anus


REVIEW


II. HumansMouth

- Mechanical and chemical digestion (saliva/chewing)Swallowing reflexEsophagus (peristalsis)Stomach

- Mechanical and chemical digestionSmall intestines

- Duodenum- Major site of chemical digestion with help from liver and pancreas

Large intestines- Water absorption- Rectum and anus

III. Humans Nutrition

chapter 20: unifying concepts of animal structure and function

Documents

connective tissue cells

major types

abundant tissue type

nervous tissue neuron

epithelial tissue2

bread cells

muscle fibers cells

similar cells