Digestive and Urinary Systems Lecture Notes

A comprehensive set of flashcards covering key vocabulary and concepts from the lectures on the digestive and urinary systems, as well as metabolism.

Which organ absorbs most organic nutrients?

B. Small intestine

Which organ primarily absorbs water and minerals?

B. Large intestine

Mechanical digestion in the large intestine is called:

C. Haustral churning

Chemical digestion begins in the:

B. Mouth

The esophagus moves the bolus using:

B. Peristalsis

Which system increases digestive activity during rest?

B. Parasympathetic NS

Local digestive control occurs via the:

A. Enteric nervous system

The nonliving layer of the tooth is:

C. Enamel

The layer rich in nerves and blood vessels is:

D. Pulp

Which enzyme begins carbohydrate digestion?

A. Salivary amylase

Salivation is mainly triggered by:

B. Parasympathetic stimulation

Swallowing is:

C. Both active and passive transport

Esophageal movement of food is:

A. Peristalsis

HCl and intrinsic factor are secreted by:

B. Parietal cells

Pepsin digests:

B. Proteins

The cephalic phase is stimulated by:

C. Thought/smell/sight of food

Mechanical stomach digestion occurs by:

C. Mixing waves

Bile is produced in the:

A. Liver

Bile is stored and concentrated in the:

B. Gallbladder

The function of bile salts is:

B. Emulsify fats

Pancreatic bicarbonate:

B. Neutralizes stomach acid

Small intestine enzymes come from:

B. Pancreas & SI epithelial cells

Small-intestine mechanical digestion:

B. Segmentation

Mass peristalsis occurs:

B. 1–3× per day

Voluntary control of defecation controls:

B. External sphincter

Defecation starts when:

B. Stretch receptors in rectum fire

The internal anal sphincter is:

C. Parasympathetic

Filtrate first appears in the:

B. Glomerular capsule

Which is NOT in filtrate?

C. Plasma proteins

Filtration occurs because:

B. HP is high in glomerulus

Net filtration pressure =

B. HP − OP

GFR stability is maintained by:

C. Autoregulation

Strong sympathetic stimulation:

B. Lowers GFR

Chronic hypertension damages:

B. Glomerulus

The PCT reabsorbs:

C. 65%

Descending limb absorbs:

B. Water

Ascending limb absorbs:

B. Na⁺, Cl⁻

Medullary gradient is from:

A. Na⁺ & urea

Tubular reabsorption uses:

C. Both

Glucose reabsorption requires:

B. Na⁺-glucose cotransport

A transport maximum occurs when:

B. All transporters are occupied

Water conservation uses:

B. Aquaporins

ADH increases:

A. Aquaporins

Aldosterone increases:

B. Na⁺ reabsorption

Tubular secretion moves substances from:

B. Blood → tubule

Substances secreted include:

B. Urea, NH₄⁺, H⁺, K⁺

Secretion helps regulate:

A. pH

Bladder stretch is detected by:

B. Stretch receptors

Micturition reflex center:

B. Spinal cord (S2–S4)

Parasympathetic activity:

B. Contracts detrusor

Voluntary urination uses the:

B. External sphincter

Voluntary urination originates in:

C. Cerebral cortex

Even with detrusor contraction, urination requires:

A. External sphincter relaxation

Catabolism is:

B. Breaking down molecules

Anabolism is:

Building larger molecules using energy

Which is an example of catabolism?

Beta-oxidation

Which is an example of anabolism?

Gycogenesis

ATP is the “energetic currency” because:

C. ATP transfers energy from catabolism to power other reactions

Cells earn ATP by:

B. Catabolism of organic monomers

Cells spend ATP on:

C. Muscle contraction & active transport

Glycolysis converts glucose (6C) into:

B. 2 pyruvate (3C each)

Link reaction converts pyruvate (3C) into:

B. Acetyl-CoA (2C) + CO₂

TCA cycle releases how many CO₂ per acetyl-CoA?

C. 2

Which pathway requires an ATP investment?

A. Glycolysis

Which process produces the MOST ATP?

C. ETC

Which process produces the MOST NADH?

C. TCA cycle

Which process CONSUMES NADH and FADH₂?

D. ETC

Which process consumes oxygen (O₂)?

D. ETC

Glycolysis occurs in the:

B. Cytosol

TCA cycle occurs in the:

C. Mitochondrial matrix

ETC occurs in the:

C. Inner mitochondrial membrane

When does the body rely ONLY on glycolysis + fermentation?

B. Intense exercise with low O₂

ETC pumps which molecule across the membrane?

C. H⁺ (protons)

The enzyme that uses the proton gradient to make ATP is:

B. ATP synthase

Beta-oxidation breaks down:

B. Fatty acids

Beta-oxidation produces:

B. Acetyl-CoA

Deamination removes the amine group from:

C. Amino acids

Deamination occurs in the:

B. Liver

The amine group becomes:

B. Urea

Which part of the amino acid yields ATP?

B. Carbon skeleton

The hepatic portal vein carries blood:

B. From GI tract to liver

Glycogen is stored in:

B. Liver & muscle

Glycogenesis is:

B. Formation of glycogen

Lipogenesis forms:

B. Triglycerides

Lipolysis breaks down:

A. Triglycerides

Gluconeogenesis is:

A. Making glucose from monomers

Gluconeogenesis occurs in the:

B. Liver

The absorptive state occurs:

C. In the first 4 hours after a meal

The main hormone of the absorptive state is:

C. Insulin

The post-absorptive state begins:

B. 4+ hours after a meal

The main hormone of post-absorptive state is:

B. Glucagon

Lipolysis is dominant during the:

B. Post-absorptive state

Glycogenesis occurs during the:

A. Absorptive state

Glycogenolysis occurs during the:

B. Post-absorptive

Gluconeogenesis occurs during:

B. Post-absorptive

Lipogenesis occurs during:

A. Absorptive state

The satiety (fullness) hormone is:

B. Leptin

The hunger hormone is:

B. Ghrelin

Hormones that increase metabolic rate:

B. T3 & T4

If body temperature drops, T3/T4 levels will:

C. Increase