Life Processes

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What are life processes?

The processes which together perform this maintenance job are life processes

What is nutrition?

Process to transfer a source of energy from outside the body of the organism, to the inside.

Most food sources are ______ based

Carbon

What is the most common chemical mean to break down molecules?

Oxidizing - Reducing reactions / Redox reactions

What is respiration?

The process of acquiring oxygen from outside the body and to use it in the process of break down of food

Chemical equation for formation of glucose

6(CO2) + 12(H2O) = C6H12O6 + 6(O2) + 6(H2O)

Chemical representation of the compound of glucose

C6H12O6

What are the events that occur during photosynthesis?

Absorption of light energy by chlorophyll
Conversion of light energy to chemical energy and splitting of water molecules into hydrogen and oxygen
Reduction of carbon dioxide to carbohydrates

What are Stomata?

Tiny pores present on the surface of leaves

What is the function of Stomata?

Massive amounts of gaseous exchanges take place through the stomata for the purpose of photosynthesis

Why does the stomata get closed?

Large amounts of water can also be lost through the stomata, so the plant closes when it does not need carbon dioxide for photosynthesis

What is the function of guard cells?

The opening and closing of a stomata pore

How do guard cells open/close a stomata pore?

• Swell when water flows into them, causing stomata to open

• Stomata closes when guard cells shrink

Autotrophic nutrition

Organisms synthesize their own food

Heterotrophic nutrition

Organisms depend upon other organisms for food

Examples of parasitic nutrition

• Cuscuta (Amar-bel)

• Ticks

• Lice

• Leeches

• Tape Worms

What does the food vacuole inside the Amoeba do?

• Complex substances are broken down into simpler ones and diffuse into the cytoplasm

Where does the undigested material go to?

• Its moved to the surface and thrown out

What is the alimentary canal?

• A long tube extending from the mouth to the anus

What enzyme does Saliva contain?

• Salivary Amylase

What does Salivary Amylase do?

• Breaks down starch to give simple sugar

The food is taken to the stomach from the mouth through what?

• Through the Oesophagus (food pipe)

What glands are present within the stomach wall?

• Gastric Glands

What do Gastric Glands release?

• Hydrochloric Acid

• Pepsin (Enzyme)

• Mucus

What is Pepsin?

• A protein digesting enzyme

In what condition can Pepsin do its designated task? (Hint: HCL)

• HCL creates a acidic medium in which Pepsin can act

How does food exit from the stomach to the intestines?

• The exit of food from the stomach is regulated by the Sphincter muscle

• The Sphincter muscle releases the food in small amounts into the small intestine

Where does complete digestion of carbohydrates, proteins and fats occur?

• Small intestine

The small intestine recieves secretions from _____ and ________

• Liver and Pancreas

The food coming from the stomach must be made ________ for the pancreatic enzymes to act

• Alkaline

What does Bile do?

• Bile salts (present within) break down fats into smaller globules increasing the efficiency of enzyme action

What does Pancreatic Juice contain?

• Trypsin

• Lipase

What is the function of Trypsin?

• Digests protein

What does lipase do?

• Breaks down emulsified fats

The walls of the small intestine contain _____ which secrete __________ _____ .

• Glands which secrete Intestinal Juice

What do the enzymes present within the Intestinal Juice do?

• Convert:
  Proteins to Amino Acids
  Complex carbohydrates to glucose
  Fatty acids into Glycerol

The inner lining of the small intestine has numerous finger like projections called _____

• Villi

What is the function of Villi?

• They’re supplied with blood vessels that take the absorbed food to each and every cell of the body

Where does the unabsorbed food go?

• To the large intestine where its wall absorb more water from this material

• Rest of the material is removed via the anus

The exit of this waste material is regulated by the ____ _________

• anal sphincter

Break down of glucose by various pathways

Why is diffusion for respiration not suitable for humans/large animals?

• Diffusion pressure alone cannot take care of oxygen delivery to all parts of the body.

Why is smoking injurious to health?

• Cilia present in the upper part of the respiratory tract

• Cilia helps to remove germs, dust and other harmful particles from inhaled air.

• Smoking destroys cilia

What does blood do?

• Transports food, oxygen and waste material in our bodies

Blood is a __________ tissue

• Connective

Blood contains a fluid medium called?

• Plasma

Plasma function

• Transports food, carbon dioxide and nitrogenous wastes in dissolved form

Why does the human heart have two different chambers?

• Both oxygen and carbon dioxide have to be transported by the blood, the heart has different chambers to prevent the oxygen-rich blood from mixing with the blood containing carbon dioxide.

Why do ventricles have thicker muscular walls than atria?

• They have to pump blood into various organs.

Why are the valves present in the chambers?

• They ensure blood does not flow backwards when the atria or ventricles contract

What is blood pressure?

• The force that blood exerts against the wall of a vessel

Blood pressure is higher in? (Arteries or Veins)

• Arteries

Systolic Pressure

• Blood pressure inside the artery during contraction

Diastolic Pressure

• Blood pressure inside the artery during relaxation

Normal systolic and diastolic pressure values

• Systolic: 120 Hg

• Diastolic: 80 Hg

How is blood pressure measured?

• Through a Sphygmomanometer.

High blood pressure is called?

• Hypertension

Negative effects of Hypertension

• Rupture of an artery and internal bleeding

How is hypertension caused?

• Constriction of arterioles resulting in increased resistance to blood flow

Arteries

• Carry blood away from heart

• Thick, elastic walls

Veins

• Collect blood from different organs

• Carry blood towards the heart

• Do not have thick wallls

• Have valves that ensure that the blood flows only in one direction

Capillaries

• Smallest blood vessels with walls one cell thick

Where does exchange of material between blood and surrounding cells take place?

• Capillaries

Capillaries join together to form _____

• Veins

Platelets

• Prevent blood leakage by helping to clot the blood at points of injury

Lymph

• Plasma, protein and blood cells that escaped through the pores in the walls of capillaries escape into intercellular spaces to form Lymph

• Similar to blood but it is colorless and contains less protein

• Lymph drains into Lymphatic capillaries to form large Lymph vessels that open into larger veins.

• Lymph carries digested and absorbed fat from intestine and drains excess fluid from extra celullar space back into the blood.

Why is diffusion not suitable for the absorption of substances a plant needs?

• If the distance between soil contacting organs and chlorophyll are small, diffusion works fine

• If large, it will not be sufficient to provide raw material in leaves and energy in roots.

Xylem

• Moves water and mineral obtained from the soil

Phloem

• Transports products of photosynthesis from the leaves where they are synthesised to the other parts of the plant

How does Xylem transport water from the ground to the plant?

• At the roots, cells in contact with the soil actively take up ions.

• This creates a difference in the concentration of these ions between the root and the soil.

• Water therefore, moves into the root from the soil to eliminate this difference

How else do plants get water from the xylem up to the highest points of the plant body?

• The water lost in the stomata is replaced by water in the xylem vessels.

• Evaporation of water molecules from the cells of a leaf creates a suction which pulls water from the xylem of the cell roots

• This process is known as transpirational pull

Transpiration

• Loss of water in the form of vapour from the aerial parts of a plant

What does transpiration aid with aside from transpirational pull?

• Temperature regulation

• During the day when the stomata are open, the transpirational pull becomes the major driving force of water in the xylem

Translocation

• Transport of soluble products of photosynthesis

What are all that the Phloem transports?

• Products of photosynthesis

• Amino acids

• Other substances

Where does the translocation of food and other substances take place? With the help of?

• In the sieve tubes with the help of adjacent companion cells both in upward and downward directions

How is translocation performed?

• Through energy

• Material like sucrose is transferred into the phloem tissue using energy from ATP

• This increases the osmotic pressure of the tissue causing water to move into it.

• This pressure moves the material in the phloem to tissues which have less pressure

• This allows the phloem to move material according to the plant’s needs

What is the main function of the Kidney?

• Removal of nitrogenous waste like urea or uric acid from the blood

Basic filtration unit of the Kidney

• Nephron

What does the Bowman’s capsule do?

• Collect the filtrate

What substances are selectively reabsorbed as the urine flows along?

• Glucose

• Amino acids

• Salts

• Major amount of water

The amount of water selectively reabsorbed depends on …

• How much excess water there is in the body

Where does the urine formed in each kidney enter?

• Ureter

What is the function of the ureter?

• Connects the kidneys with the Urinary Bladder

How is urine released? Through what?

• It is stored in the bladder until the pressure of the expanded bladder leads to the urge to pass it out

• It is released through the urethra

Why would Hemodialysis be needed?

• For people with a damaged/non-functioning kidney

• This leads to accumulation of poisonous wastes in their body, which can lead to death.

How do plants get rid of excess water?

• Through transpiration

Why is oxygen excreted by plants?

• It is a waste product of photosynthesis

Where are other plant waste products stored?

• They are stored as resin and gums, especially in old Xylem.

• They also excrete some into the soil around them