EVERYTHING GRADE 11 UNIVERSITY BIOLOGY

(og cards from Iman Siddiqi)

Function of superior vena cava

brings deoxygenated blood from above the heart

Function of inferior vena cava

brings deoxygenated blood from below the heart

Function of right atrium

After blood from the superior and inferior vena cava are brought to the heart, they enter the right atrium, the first heart chamber

Function of SA nodes

SA nodes are electrochemical cells that sense when the right atrium and right ventricle are full. When they’re full, it sends a signal to the brain signaling its time for the heart to beat to contract the chambers. They’re only on the right side of the heart.

Function of tricuspid valve

it controls the flow of blood from the right atrium to the right ventricle. When the heart beats, the blood goes through the right atrium to the right ventricle. It has tendons to stop the blood from going back up.

Function of right ventricle

Blood from the right atrium fills up the ventricle. The blood is still deoxygenated. Once the SA nods signal the venticle is full, the ventricle squeezes and the blood exits up and out through the pulmonary semilunar valve

Function of pulmonary semilunar valve

Controls the blood flow from the right ventricle to the pulmonary arteries. It allows blood to flow out, and not back.

Function of right and left pulmonary arteries

Both: Lead to lungs for the blood to become oxygenated

Right pulmonary artery: deoxygenated blood goes to right lung to be oxygenated

Left pulmonary artery: deoxygenated blood goes to left lung to be oxygenated

Function of right and left pulmonary veins

Both: carry oxygenated blood from the lungs to the left side of the heart.

Right pulmonary vein: brings oxygenated blood from the right lung to the left atrium

Left pulmonary vein: bings oxygenated blood from the left lung to the left atrium

Function of left atrium

Oxygenated blood from the lungs goes into the left atrium to be pumped into the left ventricle. Since there’s no SA nodes in the left side, the brain assumes the left side is full when the right side is.

Function of bicuspid valve

The blood from the left atrium gets pumped to the left ventricle. The valve only lets the blood goes to the left ventricle and not back

Function of left ventricle

To pump oxygenated blood it receives from the left atrium out of the body

Function of aortic semilunar valve

controls the blood flow from the left ventricle to the aorta, and makes sure oxygenated blood goes out of the heart and not back in

Function of aorta

After blood is pumped out of the left ventricle, the blood exits out to the body through the aorta. The aorta carries the oxygenated blood to all parts of the body

Function of septum (septal wall)

Acts as a muscular wall separating the left and right sides of the heart to prevent the oxygenated and deoxygenated blood from mixing

Function of arteries

brings oxygenated blood away from heart

Function of veins

brings deoxygenated blood to heart

Why does our heart beat 2 times?

1 time to get blood from atrium to ventricle, and another time to get blood from the ventricle to out of your heart.

The sound comes from your valves squeezing shut

What is pulmonary circulation?

Blood travels from heart to lungs and back

What is systemic circulation

Blood travels from the heart to the body cells and back

What is cardiac circulation

Made up of vessels that carry blood to the heart

What is arteriosclerosis

• hardening of the arteries

• Caused by excess cholesterol and calcium in blood vessels

• Arteries lose elasticity and may cause heart to be over-exerted

• Caused by improper diet, lack of exersise, smoking

What is heart attack

• Coronary thrombosis - blood clot in artery leading to heart, heart cannot get oxygen or nutrients, muscle dies

• Myocardial infarction - dead heart muscle, requires by-pass surgery

What is heart murmur

Leaky valves

• Heart chords may be loose/broken

• Backflow/leakage of blood the wrong direction

• Improper oxygenated/de-oxygenated blood mixture

What is fibrillation

• Heart beats too rapidly, cannot push blood properly

• Often problem with SA nodes

What is congenital heart disease

“blue baby syndrome”

• Caused by hole in the septal wall

• Improper oxygenated/de-oxygenated blood mixture

What is varicose veins

Defected valves in veins cause pooling of blood

Usually occur in legs

What is hypertension

• High blood pressure

• Often associated with arteriosclerosis

• Can lead to stroke, heart attacks

What is hypotension

• Low blood pressure

• Often associated with fatigue, extreme cases: coma

What is thrombosis

• Blood clot

• Location determines severity

• Example: heart attack, stroke

Describe distinguishing features between the 6 kingdoms

• Archaebacteria

  • Prokayotic

  • unicellular

  • Auto/heterotrophs

  • Extremophiles

  • Cell walls with no peptidoglycan

• Eubacteria

  • Prokaryotic

  • Unicellular

  • auto/heterotrophs

  • True bacteria found everywhere

  • Cell walls contain peptidoglycan

• Protista

  • eukaryotic

  • mostly unicellular

  • Auto/heterotrophic

  • Plant-like, animal-like, fungus-like

• Fungi

  • eukaryotic

  • Mostly unicellular

  • heterotrophs

  • cell walls contain chitin

  • Stationary

  • mycellium

• Plantae

  • Eukaryotic

  • multicelllular

  • Autotrophs

  • cell walls have cellulose

  • Sessile

  • roots

• Animalia

  • Eukaryotic

  • multicellular

  • Heterotrophs

  • Mobile

  • No cell wall

Describe the differences between animalia and eubacteria

• Animalia

  • Eukaryotic

  • multicellular

  • Heterotrophs

  • Mobile

  • No cell wall

• Eubacteria

  • Prokaryotic

  • Unicellular

  • auto/heterotrophs

  • True bacteria found everywhere

  • Cell walls contain peptidoglycan

Describe the difference between plantae and archaebactera

• Plantae

  • Eukaryotic

  • multicelllular

  • Autotrophs

  • cell walls have cellulose

  • Sessile

  • roots

• Archaebacteria

  • Prokayotic

  • unicellular

  • Auto/heterotrophs

  • Extremophiles

  • Cell walls with no peptidoglycan

Describe the difference between protista and fungi

• Protista

  • eukaryotic

  • mostly unicellular

  • Auto/heterotrophic

  • Plant-like, animal-like, fungus-like

• Fungi

  • eukaryotic

  • Mostly unicellular

  • heterotrophs

  • cell walls contain chitin

  • Stationary

  • mycellium

Why do we need digestion?

it breaks down food into essential nutrients (like proteins, fats, carbs, vitamins, minerals) that your body absorbs for energy, growth, and cell repair, while also eliminating waste

What are the two main ways that cells use the nutrients they absorb?

Cells use the nutrients they absorb for synthesizing chemical compounds, and as sources of energy, just like how glucose is needed to make ATP.

What are the 2 types of digestion?

Chemical and mechanical

Distinguish between chemical and mechanical digestion

• Chemical digestion is when chemical reactions occur to break down the food. Some reactions use enzymes to break down the chyme, and the stomach acid uses chemicals to break down the food

• Occurs in the stomach, in the duodenum

• Mechanical digestion is the physical breaking down of food, like chewing your food into smaller pieces.

• Occurs in the mouth, in the stomach

What is an enzyme?   Would they be a part of chemical or mechanical digestion? 

An enzyme is a protein catalyst that regulates reactions that occur in living organisms. Enzymes would be a part of chemical digestion because they interact with the chemical compounds in the substrate to break it down to the molecular level.

What does it mean that enzymes are target specific?

Enzymes being a “target specific” means that it can only act on one substrate. A substrate is the molecule that the enzyme works on. For example, Maltase breaks down maltose, and sucrase breaks down sucrose.

Can you think of any pros and cons of having target specific enzymes?

• Pros: specific enzymes can work better and more optimal since they focus on building down a certain molecule rather than more. It allows them to quickly break down molecules and efficiently. Efficient breakdown = better absorption of materials.

• Cons: If a person lacks a certain enzyme, the substrate wouldn’t be able to be digested properly. If the body doesn’t produce enough enzymes, it can impair the digestion of the substrate and affect how many key nutrients are absorbed.

Describe the stages of digestion

• Ingestion is when you eat the food. You put it in your mouth and chew it, and then swallow it. It is to get food into our digestive system

• Digestion is when the food you ingest makes its way down the esophagus and into the stomach. The pieces of food form a bolus in the esophagus. The bolus goes into the stomach and get broken down into chyme by the stomach acid to get it smaller.

• Absorption is when Nutrients from food and materials pass through a membrane and go into the bloodstream.

• Elimination: Getting food out of our digestive system. The chyme that forms turns into fecal matter after all the nutrients get absorbed

What is peristalsis and why is it vital for functioning of the digestive system?

Peristalsis is a wave-like muscle contraction that helps push substances (food, bile) down organs such as the esophagus and intestines, and to churn food in the stomach. It is vital for functioning of the digestive system because it is what moves the food through each stage of the digestive process. Even if the body is upside down, peristalsis will make sure that the food makes its way through the digestive tract.

What happens to food while it is still in your mouth?

When food is still in your mouth, mechanical digestion starts. The salivary glands produce saliva to chemically digest the food. The mouth secretes water, mucus, and a starch digesting enzyme called amylase. The epiglottis closes the trachea and opens the pharynx, leading to food to the esophagus. The esophagus transports food to the stomach through peristalsis, and the lower esophageal sphincter closes to prevent food from coming up.

How is the stomach involved in both mechanical and chemical digestion?

Mechanical Digestion	The stomach churns the food to physically break it down into smaller pieces. This allows there to be more surface area to cover, breaking down the bolus into chyme easier.
Chemical Digestion (general)	The initial protein digestion starts here. The stomach produces stomach acid which breaks down the food even more so the nutrients can be closer to being broken down to a molecular level.
Chemical Digestion (specific)	The gastric juices the stomach contains are hydrochloric acid, which breaks down fiber, and enzymes and pepsin, which further break down proteins

Why is the liver considered a “processing plant”? 

Tiny processing plants in the liver called lobules filter the blood that comes from the hepatic artery and the hepatic portal vein. This fills the liver with nutrients such as carbs, fats, and vitamins that it sorts, processes, and stores. The blood also delivers the oxygen needed for the liver to function. The liver breaks down these nutrients into energy and sends the filtered blood back out.

Why is the liver considered a “storehouse”?

When the body has leftover nutrients that it doesn’t immediately need, the liver stores them until the body needs those nutrients in the future.

Why is the liver considered a “manufacturing hub”?

Sometimes our blood contains products that are toxic and useless, so the liver either converts it to a product that can’t hurt the body, or isolates it and sends it to the kidneys and intestine to be excreted. The liver also makes stuff such as various blood plasma proteins that transport fatty acids and help form blood clots, cholesterol that helps the body create hormones, vitamin D and substances that help with digestion, and bile.

What is bile?

The liver uses hepatocytes to convert toxic waste products into a bitter greenish liquid called bile. This liquid is funneled into a small container below the liver called the gall bladder, before being put into the intestine to help break down fats, destroy microbes, and neutralize extra stomach acid. It also helps carry extra toxins from the liver out of the body

How do the presence of multiple enzymes, length and twisting shape, and amount of villi of the small intestine lead to more absorption of nutrients?

Feature of Small Intestine	How it increases absorption
Presence of multiple enzymes	The multiple enzymes break down complex food molecules in the chyme into their smallest and most absorbable units. This allows almost all of the nutrients in the chyme to be absorbed into the body since they’re all small enough to be absorbed
Length and twisting shape	The length of the small intestine and the twisting shape lets the chyme stay in the intestine for longer, allowing for more time to fully absorb all the nutrients in the chyme.
Amount of villi	The large amount of villi on the walls of the small intestine increase the surface area of the intestine’s internal area, which allows for more contact with the chyme to better absorb and efficiently absorb the most nutrients possible.

Why are the terms ingestion, absorption, digestion, and egestion important when learning about the digestion system?

they define the four fundamental stages of transforming food into energy

Function of the teeth:

• Part of mechanical digestion and ingestion

• Invisors - bite food to get it into our mouth (fromt 4 teeth)

• Molars - grind food down

• Bicuspids - Canines, tear meat.

Function of the toungue

• Part of ingestion and moves food towards teeth, aiding in mechanical digestion

• Moves food into esophagus

• Helps us eat the right food

Function of salivary glands

• Part of ingestion and chemical digestion

Produces saliva which:

• makes food softer and slippery

• Makes food easy to swallow and start digestion

• Salivary amylase breaks down amylose (carb)

Function of uvula

• Ingestion

• Hanging ball at the back of your throat that stops food from going up your nose

Function of Epiglottis

• Ingestion

• A flap of skin that closes the trachea so that food doesn’t go in your lungs

Function of esophagus

• Ingestion

• Performs peristalsis

• Connects the oral cavity to stomach

• Doesn’t have a very good mucus lining which can lead to heart burn

Function of cardiac sphincter

• Ingestion because it opens to let the bolus into the stomach

• Digestion because it stays closed so the stomach acid doesn’t go back up

• A ring of muscle that squeezes and closes and relaxes and opens. It connects the esophagus to the stomach

Function of the stomach

1. Mechanical Digestion: has 3 layers of muscle to churn the food

2. Chemical digestion: produces hydrochloric acid and releases an enzyme called pepsin

3. Produces mucus for protecting itself and the lining from stomach acid.

Function of pyloric sphincter

• Digestion - Controls the release of chyme from the stomach into the duodenum and makes sure the chyme is only releaseed when it is properly digested from the stomach. It stays closed so that the chyme can stay in the stomach longer

• Absorption - regulates the rate of how fast chyme enters the duodenum, preventing the small intestine from being overwhelmed.

Function of the liver

• Digestion: Produces bile and sends it through the duodenum. The bile goes down the hepatic duct to the common bile duct into the duodenum

Function of gallbladder

• Digestion: stores extra bile in case needed. Sends bile through the cystic duct to the common bile duct into the duodenum

Function of pancreas

• Digestion: Produces enzymes like trypsin and pancreatic amylase along with pancreatic juices that release bicarbonate for protecting the duodenum from stomach acid by neutralizing it

• Sends it through pancreatic duct to the common bile duct and then to the duodenum

Function of small intestine

• Digestion: Completes the digestion or carbs, fats, and proteins. Bile from the liver and gallbladder and enzymes from the pancreas go into the duodenum and mix with the chyme to break it down to a molecular level. The long and twisty structure also let the food sit in the small intestine longer, allowing it to have enough time to break down

• Absorption: structures called villi in the small intestine line the surface to increase absorption surface area

Parts of the small intestine

• Duodenum: first part of the small intestine, enzymes and bile from the common bile duct enters it and neutralizes stomach acid and further digests it to its best ability

• Jejunum: the middle section, food is still digesting, and the jejunum absorbs the most nutrients from the food with villi

• Ileum: final section, absorbs essential nutrients and the rest of the fats, proteins, and carbs. It passes undigested material to the large intestine.

Why is the small intestine so good at its job?

It’s really long and twisty which keeps food in our body longer for better absorption, and also so the chyme can be digested to its smallest form

Function of the Ileocecal sphincter

• Digestion: stays closed so chyme can stay in small intestine for longer

• Absorption: stays closed which allows more time for nutrient absorption

• Egestion: Allows undigested matter to enter the large intestine

In between small intestine and large intestine

Function of large intestine

• Absorption: Reabsorbs water

• Egestion: The cecum (first part) Forms the shape of fecal matter

Has a really good environment to house good bacteria that can make vitamin b and vitamin k for us. The good bacteria also takes up space so no bad bacteria can grow.

Function of Anal sphincter

• Egestion: releases fecal matter

Describe how proteins get digested

• In the stomach: The polypeptides get broken down by the pepsin in the stomach to produce peptides.

• The peptides get broken down in the duodenum by trypsin from the pancreas to produce dipeptides

• The Dipeptides get broken down into amino acids in the small intestine by Erepsin from the walls of the small intestine

Describe how fats/lipids get digested

• In the stomach they are triglycerides.

• In the duodenum, bile from the liver breaks them down. Lipase from the pancreas then breaks the triglycerides into Glycerol + fatty acids in the small intestine

Describe how carbs like starch get digested

• In the mouth: Salivary amylase from the salivary glands break down starch to Amylose.

• In the duodenum: Pancreatic Amylase from the pancreas breaks down amylose to maltose

• In the small intestine: Maltase from the lining of the small intestine breaks down maltose into 2 glucose molecules

Describe how carbs like milk get digested

• In the duodenum: Pancreatic amylase breaks down milk into lactose

• In the small intestine: lactase from the small intestine breaks down lactose into 1 glucose and 1 galactose molecule

Describe how carbs like apples get digested

• In the duodenum: Pancreatic amylase from the pancreas breaks down the apple into sucrose

• In the small intestine: Sucrase from the small intestine breaks down sucrose into glucose and fructose

What stages do all carbs go through when being digested?

1. They are polysaccharides

2. They become disaccharides

3. They become monosaccharides

What are 2 examples of digestive disorders?

• Acid reflux: stomach acid flows back into the esophagus causing heartburn

• Ulcers: When the stomach acid erodes the stomach lining causing pain and indigestion

Why does our body need carbs?

They are the body's primary and preferred source of quick energy, broken down into glucose to fuel the brain, muscles, and cells.

Why does our body need protein

Proteins are used for repair in cells because they are the building blocks that build up the cells. The code for the proteins that build up everything in the cell is stored in the DNA. Whenever the cell undergoes damage, the proteins get used to fix whatever is wrong structurally.

They also provide amino acids

Why does our body need vitamins

Vitamins are needed for cells to stay healthy and to protect against damage. Vitamins maintain the immune system by supporting it and providing nutrients to keep the cells healthy.

Why do we need to breathe?

We breathe because we need oxygen to help convert the energy in our food into ATP so we can use it for energy to run our bodies. (aerobic respiration)

What is the difference between the terms gas exchange and ventilation?

Gas exchange is when oxygen diffuses into the body’s cells and carbon dioxide diffuses out of the cells. Ventilation is when oxygen-rich air is moved to the lungs, and carbon dioxide-rich air  away from the lungs.

What are some places where gas exchange occurs?

1. gas exchange occurs in the lungs where oxygen diffuses from the air into the bloodstream, and carbon dioxide diffuses from the bloodstream into the lungs.

2. Gas exchange also occurs in body cells where oxygen diffuses from the bloodstream into each body cell, and carbon dioxide diffuses from the cells into the bloodstream to be carried back to the lungs for removal.

Describe the 2 main stages of breathing:

1. Inhalation: When we breathe in, the rib cage moves up and out, and the diaphragm contracts and moves down. The intercostal muscles contract to pull the ribs up and out. The Pressure in the lungs decreases, causing air to rush in.

2. Exhalation: When we breathe out. The rib cage moves down and in, and the diaphragm relaxes and moves up. The intercostal muscles relax and move the rib cage down and in. The Pressure in the lungs increases, causing air to move out.

Oxygen Transport: at Tissues

• Oxygen in lungs diffuses from alveoli.

• Oxygenated blood travels to the pulmonary vein.

• Heart pumps blood to the aorta.

• Oxygen diffuses from capillaries to body tissues.

• CO2 moves from body tissues to hemoglobin in red blood cells

Carbon Dioxide Transport

• CO2 diffuses from tissues and attaches to hemoglobin on red blood cells.

• Deoxygenated blood travels to the pulmonary artery.

• Heart pumps blood to the lungs.

• In the lungs, CO2 diffuses from blood in the capillaries to the alveoli.

• CO2 is exhaled.

Controlling Breathing

• Breathing is controlled by nerve impulses from the medulla oblongata (brainstem).

• Brain does not monitor oxygen levels, it monitors CO2 levels.

• High CO2 levels in blood increase and trigger faster, deeper breathing

• Brain sends signals to the diaphragm and intercostal muscles to contract faster or slower

Lung Capacity: What are the 4 factors that affect breathing? Explain how they affect breathing

• Gender: Males generally have larger lungs and airways which leads to more lung capacity, compared to females, who have smaller lungs and narrower airways

• Body type: Obesity restricts the lungs and reduces the lung capacity because of excess fat. Taller people have a larger thoracic cavity, which increases lung capacity. People with a wider and longer chest have more lung capacity since there’s more room to expand.

• Age: As you get older, your lung tissues get less elastic, and your breathing muscles get weaker, making the  rib cage stiffer.

• Health: physical fitness strengthens respiratory muscles and allow tissues to stay elastic. Smoking damages alveoli causing inflammation, scarring, and excessive mucus production which can lead to chronic bronchitis. Infection causes inflammation, fluid buildup in the alveoli, and excess mucus, which obstructs airflow and oxygen exchange, leading to breathlessness and fatigue

Define total lung capacity

The maximum volume of air that can be taken into the lungs during a single breath.

Define tidal volume

The volume of air inhaled or exhaled during a normal, instinctive breath

Define vital capacity

The maximum tidal volume ( the maximum amount of air that can be inhaled or exhaled)

Define VO₂

An estimated or measured value representing the rate at which oxygen is used in the body. 

Measured in millilitres per kilogram per minute.

What does air conditioning mean?

Changing the air we breathe to make it suitable for our body

Cleaning, warming, moistening

What does it mean to clean, warm, and moisten the air?

• Cleaning: We need to filter out the stuff we don’t need so it doesn’t clog the alveoli and cause lung infection

• Warming: Our normal body temp. is 37 celsius. We don’t want to breathe in cold air and mae our blood cold, which could harm homeostasis, which is why we need to warm the air

• Moistening: Oxygen gas cannot enter our blood stream. We need dissolved, liquid oxygen to enter our blood

What is the function of the nose?

Produces mucus that moistens the air due to it being watery, and traps dust. Nose hairs filter our solid particles out of the air.

Our nose has a lot of capillaries that make our nostrils warm, which helps warm the air.

What is the function of the Pharynx

Like a common area or front foyer

Leads to 4 diff. pathways:

• Going back out: nasal cavity, mouth

• Going in: Trachea, esophagus

Contains mucus which helps clean, warm, and moisten the air.

Function of epiglottus

Mostly open since we breathe all the time

When we swallow, the tongue pushes it back, closing it

Function of trachea

feels like a ribbed straw due to cartilage rings. Cartilage rings keep it open so air can always go through.

It connects the pharynx to the bronchi

It contains mucus to clean, warm, and moisten the air

Function of Bronchi

First 2 tubes coming off of trachea

Has a mucus lined membrane to clean, moisten, and warm the air

Has no cartilage, so if they collapse, its difficult to open them back up

Function of bronchioles

Smaller tubes that branch off of the bronchi

No cartilage

Function of Alveoli

A tiny sac of air that is really thin in order to make the diffusion of oxygen possible

They require a coat of water lining their membrane because the oxygen gas has to be dissolved in water in order to be dissolved into the bloodstream